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1vn101 | Why was there a large quantity of music from Europe, Africa, India while other countries in Asia or the (Native) Americas are barely represented? | Specifically, I'm talking about Music Bands, Choirs & Orchestras would play. As a Choir Student, I've sung my large scale of European and African pieces, but I've never sung nor heard a song from Asia nor from Native Americans. Are there any Historical explanations for this, or am I not exposed to enough variety? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1vn101/why_was_there_a_large_quantity_of_music_from/ | {
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" > Music Bands, Choirs & Orchestras\n\nThat sounds very very European... Most of the standard repertoire was composed by European musicians, it is still very normal to find a lot of their music if you are into the Western musical tradition (even if you are somewhere else in the world). \n\nEuropean concert music certainly made an influence in lots of places, and we find composers from the times of the European colonies, plus music composed once countries became independent. These days we can find new music in the classical tradition being composed by musicians from many different cultures. \n\nSo called classical music has had a big \"museum\" component in the last 150 years. Mozart is a household name while many other composers are not known even in their native countries...\n\nIf you are after old music in the Western tradition composed by people born out of Europe, I can tell you about some \"Mexican\" composers:\n\n* [Juan de Lienas (born c. 1640)](_URL_5_)\n\n* [Manuel de Sumaya (born in 1678, first person born in the Western hemisphere to compose an opera with text in Italian)](_URL_0_)\n\n* [José Manuel Aldana (born 1758)](_URL_8_)\n\n* [Manuel Arenzana (1762)](_URL_4_)\n\nThere were quite a few musicians working in what is now Mexico who were born in Spain (and maybe somewhere else in Europe), their music is now considered part of the musical practice of Mexico from that period (some lived most of their lives here). For example:\n\n* [Hernando Franco](_URL_3_). Born in Spain in 1532. The text from that video is in Nahuatl, I think.\n\n* [Juan Gutiérrez de Padilla](_URL_2_) Born in Spain in 1590.\n\n* [Ignacio Jerusalem y Stella](_URL_10_) Born in Italy c. 1707.\n\nWe suspect some composers from the period were not of Spanish descent, or at least were not 100% Spaniards. \n\nGetting closer to our days\n\n* [Carlos Chávez (b. 1899)](_URL_9_) A piano concerto.\n\n* [Silvestre Revueltas (b. 1899)](_URL_1_) Orchestral music.\n\n* [José Pablo Moncayo (b. 1912)](_URL_7_) this is probably the most famous orchestral work by a Mexican composer.\n\n* [Arturo Márquez (b. 1950)](_URL_11_). This is his most popular work, composed in the early 90's, a live performance can be quite an impressive thing with all the brass and percussion involved. It has this visceral punch... \n\nMárquez is still composing. I heard the premiere of a choral-orchestral work a few years ago, here he used famous speeches. There's this VERY strong movement with the text being some parts of Dr. King's I have a Dream. In my opinion, the best part of that choral work is the one with a baritone, based on a speech by \"an Indian chief.\" I am afraid I cannot find recordings of these...\n\nThere are lots of Mexican composers with quite dissonant compositional languages, too. I just went to list easy to listen examples. \n\nI mentioned Mexican composers because, being Mexican, I am more familiar with those. But there are examples from other parts of the world.\n\n* [Chen Gang, He Zhan-hao](_URL_12_) Violin concerto composed in 1959, in China.\n\n* [Alberto Ginastera (b. 1916)](_URL_6_) A piano sonata by an Argentinian composer.\n\n**TL;DR**\n\nIt was \"dead white men\" for a while, but there is certainly more to it. The Western musical tradition has been absorbed all around the world, you can find examples from many places. Ask your teachers and conductors, they might be able to give you some suggestions to start listening to less famous people. If they aren't into that kind of thing, I am sure it will be easy to ask in the musical subreddits for more suggestions."
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"https://www.youtube.com/watch?v=T3dNAIhzcGs",
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"https://www.youtube.com/watch?v=EF4UDYwXt10",
"https://www.youtube.com/watch?v=h5clRUGP8MM",
"https://www.youtube.com/watch?v=2MZF31kyF4o",
"https://www.youtube.com/watch?v=7-lcnVAoLRE",
"https://www.youtube.com/watch?v=dkVcwrL1hog",
"https://www.youtube.com/watch?v=mh8kpDZ2v44",
"https://www.youtube.com/watch?v=zozW-UmloRI",
"https://www.youtube.com/watch?v=sNiQD5GY3Yg",
"https://www.youtube.com/watch?v=3vwZAkfLKK8",
"https://www.youtube.com/watch?v=sOuPpyuqcOE"
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1dzj9k | what's the point of a silent letter? | Like in ghost, Django, freljord etc.... | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1dzj9k/eli5_whats_the_point_of_a_silent_letter/ | {
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"While it may not get spoken itself, it modifies the pronunciation of nearby letters.",
"These usually come up because pronunciation changes faster than spelling. Furthermore, it's possible for a language to adopt the spelling of a word from one parent language, but the pronunciation from another - this is the case with the word \"colonel,\" which came up recently here on reddit.\n\nSo, the point of silent letters would be to retain enough of the parent word to be recognizable while allowing the pronunciation to change.",
"You play league huh?",
"As a side note, this bugged me in the movie: the D in Django is not silent. It's just that the J sound already contains a D (the phonetic notation for the J sound is /dʒ/). Just like you wouldn't say \"letuh-ter\" for letter, you don't say \"Duh-jango\" for Django."
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321y4j | instead of all the costly and/or inhumane methods of death penalty execution, why don't they just open convicts' veins and let them bleed out safely and hygienically? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/321y4j/eli5_instead_of_all_the_costly_andor_inhumane/ | {
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"You think opening their veins is the humane way ? Why would it be more humane than putting them \"to sleep\" ? Plus it's waaaaay more messy.",
"Mainly inhumane is judge as \"if they feel pain or not\". Lethal injection is the most humane we have so far. However, the convict can have a reaction to the injection. Similar to a reaction of a shot or allergie."
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srvvn | Is it possible for intelligent life to be of a different sex system? | I always watch movie or games, and while I realise that they are poor examples or representations of actual alien life, I always witness that aliens have the same genders as us, male and female. What are the chances that they follow us in this? | askscience | http://www.reddit.com/r/askscience/comments/srvvn/is_it_possible_for_intelligent_life_to_be_of_a/ | {
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"Completely random. They could be single sex, two sexes or something completely different. "
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22x4ke | How did ancient empires/kingdom (Roman Empire, Warring States) equip their armies? | So like the question is a little ambiguous I'll rephrase it here: how did those empires so much equipment to equip their armies? Did they have some sort of *"industrial-scale"* factories? Or many craftmen doing the same thing independently? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/22x4ke/how_did_ancient_empireskingdom_roman_empire/ | {
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"For the Roman Empire, the answer is that weapons and equipment were mostly provided by the private sector. In the imperial period new units were always set up in Italy, \"where they could take advantage of well-established Italian industries\" (Herz p.314). The state paid the producers and handed over the equipment to the individual soldiers, who had the costs of the equipment deducted from their pay (over a period of a few years). \n\nFor the replacement of equipment the Roman military camps included workshops where repairs could take place and small numbers of simple weapons could be produced. Larger requirements again were provided by the private sector locally. The local private sector probably wouldn't be as large scale as in Italy (depending on where the unit was stationed), so it likely included any craftsmen who were up for the job. If no sufficient local supplier(s) existed, the military would create its own production site (as happened in Britannia).\n\n-----------\n\nSource: \n\n* P. Herz, *Finances and Costs of the Roman Army* (in: P. Erdkamp (ed.), A Companion to the Roman Army, Oxford 2007, p. 306-322)",
"Hello there! The Carthaginian republic seems to have operated its own arsenals (staffed by slaves), though the foreign mercenaries and native levies that formed the bulk of their overseas armies would have supplied much of their own equipment, at least initially. When P. Cornelius Scipio (later Africanus) captured Carthage in Spain (\"New Carthage\") in 209 B.C., he found two thousand slaves who had apparently been making war materiel for the Carthaginians and promised them freedom after the cessation of hostilities if they continued working for the Romans in the meantime (Polybius 10.17.9; Livy 26.47.2); in fact, according to Livy (26.47.6), Scipio's forces had seized \"120 catapults of the largest size, 281 smaller ones, 23 larger and 52 smaller ballistae, [and] an enormous quantity of larger and smaller scorpions as well as arms and projectiles.\" Given that the Carthaginians were able to mobilize large and fully-equipped armies relatively quickly, scholars have naturally assumed that similar facilities existed elsewhere. [1] \n\nThe state also controlled shipyards. The Marsala shipwreck, a rather amazing discovery for underwater archaeologists, revealed that the Carthaginians assembled their vessels using prefabricated and probably mass-produced parts, as each component was numbered with an alphabetic construction mark. [2] Although scholars at the time were more interested in explaining how the Romans, using a captured warship as a model, were able to produce a hundred quinqueremes in sixty days at the start of the First Punic War, it also suggests in my mind some degree of central planning on the part of the Carthaginians. \n\nI hope you find this helpful! :D\n\n[1] Gilbert Charles-Picard and Colette Picard, *Daily Life in Carthage at the time of Hannibal*, transl. A. E. Foster (New York: Macmillan, 1961), 103f.; Yu. B. Tsirkin, \"The Economy of Carthage,\" in *Carthago* (Studia Phoenicia VI), ed. E. Lipiński (Leuven: Peeters, 1987), 132f. See also Anna Chiara Fariselli, \"The Impact of Military Preparations on the Economy of the Carthaginian State,\" in *Phoenicians and Carthaginians in the Western Mediterranean* (Studia Phoenicia 12), ed. Giovanna Pisano (Rome: Università degli Studi di Roma Tor Vergata, 1999), 59-67.\n\n[2] Honor Frost, \"The Prefabricated Punic Warship,\" in *Punic Wars* (Studia Phoenicia 10), ed. H. Devinyer and E. Lipiński (Leuven: Peeters, 1989), 127-35. See also Louis Rawlings, \"The Carthaginian Navy: Questions and Assumptions,\" in *New Perspectives on Ancient Warfare*, ed. Garrett G. Fagan and Matthew Trundle (Leiden and Boston: Brill, 2010), 253-87."
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3xmi01 | What's c to the power of i if c is a complex number and i the imaginary unit? | askscience | https://www.reddit.com/r/askscience/comments/3xmi01/whats_c_to_the_power_of_i_if_c_is_a_complex/ | {
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"(See sidebar of /r/math to render equations.)\n\nPowers of complex numbers are defined in terms of the exponential and logarithm functions. So we have\n\n`[; c^i = e^{i\\log(c)} ;]`\n\nwhere \"log\" is a logarithm of *c*, and there are infinitely many of them. Let's write\n\n`[; c = a+ib ;]`\n\nwith *a* and *b* real. Then\n\n`[; \\log(c) = \\textrm{Log}(\\sqrt{a^2+b^2})+i\\theta+2\\pi n i ;]`\n\nwhere \"Log\" means the usual logarithm function defined on positive real numbers, `[; \\theta ;]` is an angle such that `[; \\tan(\\theta) = b/a ;]`, and *n* is an integer. Substituting this into the definition for c^(i) gives\n\n`[; c^i = e^{-\\theta-2\\pi n}\\left[\\cos\\left(\\textrm{Log}(|c|)\\right)+i\\sin\\left(\\textrm{Log}(|c|)\\right)\\right] ;]`\n\nwhere `[; |c| = \\sqrt{a^2+b^2} ;]`.\n\n\nInterestingly, notice that if |c| = 1, then the sine term vanishes, and the final result is real. So any complex number on the unit circle to the power of *i* is actually a real number (and there are infinitely possible values)."
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40pso7 | when referencing a black hole and speaking of matter, why is it referred to as information? | I love science, and space! I love learning new things, I try to learn new things! Unfortunately I was unable to ever find information about [information](_URL_0_) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/40pso7/eli5_when_referencing_a_black_hole_and_speaking/ | {
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"My understanding is that everything in the universe undergoes change in a way where effect can be traced to cause, such that one could \"piece things back together\" step by step, given the theoretical computing power to model the universe.\n \nWith regards to black holes, the question remains whether this linkage is preserved; whether any matter that enters and undergoes could ever theoretically be pieced back together beyond the event horizon, even with such computing power.",
"If you research entropy, you may find something that makes sense to you. Because we can measure black holes in entropy, and entropy and information are equivalent (long story) we can therefore measure black holes in information. ",
"Matter is not the same as information. If I have a rock and I make it vanish, I've destroyed matter. But I haven't necessarily destroyed information. I might remember the rock. Or maybe I've forgotten about it, but there's still light moving away from it that someone far away could see to tell that it's a rock. Or it has in some other way caused the universe to be in a different state than it would be if it had been anything other than that particular rock.\n\nNow imagine I have a rock and I vaporize it. Then I erase everyone's memories and change everything so that the universe is completely identical to what it would be had that been something other than that rock. The matter's still there. But I destroyed the information.\n\nIt's generally accepted that both of these are impossible. But general relativity suggests that black holes should be able to destroy information. Sure people would remember that you tossed a rock into a black hole, but maybe that rock was radioactive, and one of the atoms decayed just before it fell in. Is there any way to distinguish a universe where that atom decayed from one in which it did not?",
"There is a scientific principle that information cannot be destroyed.\n\nI might throw a book on a fire and let it burn down to ashes, but in principle, I could take those ashes, and all the surrounding molecules of gas, and deduces from them the original book.\n\nYou can't do this with something that has passed into a black hole, however. So either the principle of information conservation is wrong, or we don't completely understand black holes. ",
"Information is a bit tricky to understand, lets start with the simplest kind of information that i can imagine, a photon it has a wavelength thats it, that is the only information that it really carries with it. If that photon is captured by a black hole the information about the photon is gone if we didnt measure it before hand, this ties together with quantum phyisics after this.\n\nLets look at a bit more complex information, imagine that you have a machine that builds an object and the information about how it was built is not saved or retrivable at all, it was made in a room without light and the machine worked as a true random. And all the information about that object is that object (whatever it might be) and you put it in a bag and toss the bag into a black hole all the information about that object seems to be lost to us, there is no way for us to retrive any information about that object.\n\nAnd according to physics information can not be destroyed, and physicists are trying to solve this problem and we seem to come to another problem when we do either we have to accept that information can be destroyed which opens up a whole host of new problems, or that locality is not real (IE things that are arbitrary far apart can interact with each other without having to abide by time or the speed of light)\n\nWhichever we try to choose we seem to break physics."
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94hc21 | Organized Crime during the Weimar Republic | The State of the Republic with its often fractured political landscape, ideological infighting, weak centralized control, changing societal attitudes that just wanted to forget the horrors of war and a growing black market due to financial uncertainty seems like the perfect breeding ground for organized Crime to spring up.
Was it rampant and if so who was leading it? Were there Cartels and how did these people earn their money? Which was their racket and did they meddle in politics? Did the political groups themselves resort to illegal activities to finance themselves?
What did the state do to fight those activities and why have I never heard of a German "Al Capone?" | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/94hc21/organized_crime_during_the_weimar_republic/ | {
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"Organised crime certainly did exist in Weimar Germany, much of it in the form of groups known as *Ringvereine*.\n\nYou can read more about them, how they were organised and what happened to them in these earlier responses, with u/commiespaceinvader:\n\n[Fritz Lang's \"M\" (1931) gives the impression of a large organized crime network in Weimar Germany. Was organized crime a large factor in in Nazi Germany as well?](_URL_0_)\n\nand with u/Abrytan:\n\n[Were there famous gangsters during the Third Reich? Or was the totalitarian nature of the regime a good deterrent for organized criminal activities?](_URL_1_)"
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31dk1u | In the Antebellum South, what was the infant mortality rate of enslaved children? | Did Slave-owners have much of an investment in keeping infant African Americans alive, or did they not care? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/31dk1u/in_the_antebellum_south_what_was_the_infant/ | {
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"Basically, we don't know precisely. Slave records are frustratingly rare, incomplete, and vague. I say this as someone who has been attempting to identify slaves belonging to one family in one decade in one state since January; I think we're up to six names (out of ninety or so slaves). For the most part, the documentation just ain't there to make quantitative comparisons.\n\nIn a broader sense, the mortality rate was higher than replacement levels during the first few decades of English slavery in Virginia, necessitating bringing in a continual stream of slaves to replenish those dead of disease and overwork, but it had significantly dropped off by the late 17th and early 18th centuries. I haven't read up on South Carolina in depth, but as the other major entry point for slaves into the colonial South, it probably experienced a similar trend. Certainly by 1808 - when the international slave trade was outlawed by the United States - slaves were reproducing at beyond a replacement rate, and with foreign importation cut off, a thriving domestic slave trade developed, whereby settlers in the Deep South (the cotton belt effectively extended from East Texas through Georgia) purchased excess slaves from the Upper South, where slave agriculture had been declining in profitability for decades, mostly due to falling tobacco prices as well as the diversification of agriculture and the economy more generally. \n\nI don't want to get into the morality of slave ownership, but I will say that a paternal aspect was often present in slave owners, at least those I have studied. Many of them genuinely thought that they were looking out for the best interest of their slaves, whom they assumed to be incapable of caring for themselves. But purely from an economic standpoint, due to the constricted supply, slaves were generally quite expensive, and slave owners were, as a rule, intensely concerned with turning a profit. For one or both reasons, slave owners generally made a basic effort to keep slaves alive and moderately content. They bought clothes for them; they purchased their garden produce for small sums of cash; and they hired doctors when slaves were sick."
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69jvma | how does sitting close to the tv affect my eyesight? it's not like i have to strain to see what i'm watching because i'm nice and close. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/69jvma/eli5_how_does_sitting_close_to_the_tv_affect_my/ | {
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"It doesn't.\n\"Contrary to the popular myth, sitting too close to a TV will not damage your eyes but it may cause eyestrain. Children can focus at close distance without eyestrain better than adults. Therefore children often develop the habit of holding reading materials close to their eyes or sitting right in front of the television. There is no evidence that this damages the eyes either in children or adults. With children, this habit usually diminishes as they grow older.\"\n\n_URL_0_]",
"I don't think it does. It affects the view of everyone else in the room when a kid sits in front of the tv. And parents use that as an excuse to make you move. ",
"It affects your eyesight the same as reading a book or staring at a wall at close range. Your eyes don't have to refocus for a long time, so they get lazy and decide they won't change their focus from the distance you're used to.\n\nAlso, needing to sit close in order to see without straining is a sign that you should have glasses already. "
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1v6g6i | How can a species evolve a counter-measure to a threat or predator, ie poison, when those that fall prey to it aren't passing on their genes? | How do those passing on the species' genes know what needs to improve when they've been successful enough to reproduce? | askscience | http://www.reddit.com/r/askscience/comments/1v6g6i/how_can_a_species_evolve_a_countermeasure_to_a/ | {
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"Actually the ones with the mutated genes which provide an advantage/countermeasure have a higher chance to survive and pass on their genes. Therefore the species evolves, sometimes quite rapidly, to cope with its new environment/enemy. Example: the peppered moth evolution:_URL_0_",
"Firstly, this take millions of years. One common aspect I find among questions about evolution is many cannot grasp how long allele fixation takes. Also it is not a concious act by any means, trilobites did not think 'hey I need armour to defend myself against other trilobites'. It took millions of years for armour to, firstly mutate and emerge, and secondly to fixate within the population. \n\nTo answer your question let us take a hypothetical example, species A and B. Species A is hunted by species B, classic predator vs. prey interactions. This trend in evolution is known as non-random processes, as opposed to neutral evolution or genetic drift. \n\nSpecie A's defence is being selected for in a neo-Darwinian fashion. Therefore the selection coefficient for alleles, i.e. coding for exoskeletons, which improve its fitness, increases. As these alleles are being selected upon, the 'weak' or those with 'lesser fitness' fall prey to the predators. Therefore in terms of the resulting offspring that are made and do survive will have overall better alleles in terms of defence. Hence the term 'survival of the fittest'. \n\nNow extrapolate this interaction for one million years. The surviving population of specie A (assuming the only allele under selection here is defence) must have the best alleles for defence. This process of reaching, what is known as, 'peak fitness' can have many small steps as well as a few rare leaps, perhaps a mutation which evolves a new arrangement of its exoskeleton. Asymmetrical interspecies 'arms races' drives evolution at a much quicker pace than, neutral or genetic drift could. ",
" > How do those passing on the species' genes know what needs to improve when they've been successful enough to reproduce?\n\nThey don't. Evolution is not a conscious process.\n\nRather, the key lies in having more offspring than the environment can support. A layman's analogy: If the environment can support 100 frogs and 1,000,000 are born, only about the 100 best (luck is only a minor factor long term) frogs will grow to reproduce and pass on their genes. It is more likely that these frogs have some kind of adaptation to their environment. \n ",
"This its very simple. If you succumb to a poison or threat you die and do not pass on your genes. \n\nThe idea is that the animal that doesn't succumb to the threat or predation does pass on its genes. \n\nTherefore only the animals that can adapt or have a select advantage to survive these threat situations are in fact the only ones able to pass on the genes. \n\nTo the question of evolution. If an animal is born with a mutation and that animal benefits from said mutation, there is a higher likelihood of that mutation being passed on through the above method. The greater the benefit the higher the the survivability the greater the chance to pass on the genes. \n\nSo in effect it is precisely the animal that can not adapt to a threat or predation that is unable to pass on the genes. This is natural selection. "
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4vwu6i | What was the largest city in the Americas 1000 years ago, before Tenochtitlan (the Aztec capital) was built? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4vwu6i/what_was_the_largest_city_in_the_americas_1000/ | {
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"That would be Teotihuacan, located just northeast of where Mexico City is today in a sub-valley of the Valley of Mexico. At its height, Teotihuacan had a population of between 100,000 and 200,000 people. It's ceremonial core, which is what you mostly see today in the partially restored and open tourist area of the city, covers about 26 km2. Throughout the city's life different neighborhoods and regions were occupied at different times and for whatever reason were abandoned and then reoccupied. Surveys in the 60s by Rene Millon and his team had found that the total area the city covered was 53 km2, with the outer edges of the city consisting of households spaced further apart in order to farm or grow gardens.\n\nDespite it's Nahuatl sounding name, we don't actually know what the city was called, what the people that occupied the city called themselves, or even what language they might have spoken. The name of the city was bestowed upon Nahuatl speakers who came across the ruins hundreds of the years after the city's abandonment. The name itself is translated as \"the place where gods were born\", but whether this had to do with the impressive size of the pyramids of the Sun and Moon, whether this has anything to do with Aztec belief, or something else is uncertain.\n\nTeotihuacan seemed to have meddled in Maya affairs in the 300s going so far as what some might think is an invasion. The ruler of Tikal, a very powerful city-state in the Maya region, had its ruler deposed with someone who had strong ties to Teotihuacan put in their place. While this is an information blackout period at Tikal with little in the way of writing about the events, other sites have documented this entrada. What's curious about this entrada is that Maya artists depict these foreigners not in their own Maya artistic portrayal of people, but in the way Teotihuacan depicts its people. So see monuments with two different art styles along with iconographic elements not previously found in Maya artwork. The emphasis on these foreigners using atlatls is interesting because atlatls were not necessarily the weapon of choice among the Maya, but were the weapon of choice among Teotihuacanos. Within those monuments the Maya had said that these foreigners came from a placed called *Pu*, which in Maya means \"place of many reeds\". However, in Mesoamerica a place of many reeds simply meant a city with many people. In Nahuatl the term is Tollan which you may have heard. Many of the cities in Central Mexico had Tollan attached to their name like Tula Tollan for the Toltecs or Cholula Tollan in Puebla. While the name *Pu* may not have been the Mayanized name for Teotihuacan, it is interesting to know that the association of densely populated cities with a place of many reeds stretches that far back in Mesoamerican history."
]
} | [] | [] | [
[]
] |
||
1pquyg | that feeling you get in the pit of your stomach when looking over the side of a tall building. | Or something else that scares you. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1pquyg/eli5_that_feeling_you_get_in_the_pit_of_your/ | {
"a_id": [
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"text": [
"It's the fight or flight response. When you encounter something that is frightening or potentially threatening, your body releases hormones like adrenaline to help you prepare to deal with it. That feeling is a side effect of the hormones.",
"l'appel du vide yo"
]
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[],
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|
uq619 | Is it true that a car would use more gas to turn off and then on instead of idling for five minutes? | askscience | http://www.reddit.com/r/askscience/comments/uq619/is_it_true_that_a_car_would_use_more_gas_to_turn/ | {
"a_id": [
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"text": [
"No. It does cost some amount, [but it only takes 10 seconds of idling to spend more than that amount](_URL_1_) \n\nEdit: the details of exact timing may differ from article to article I've seen. Here's another one: _URL_0_\nLet's just say, order of magnitude is ~10s of seconds",
"I heard it used to be true, but technology improved the startup efficiency quite a while back."
]
} | [] | [] | [
[
"http://www.slate.com/articles/health_and_science/the_green_lantern/2008/05/is_an_idle_car_the_devils_workshop.html",
"http://www.consumerenergycenter.org/myths/idling.html"
],
[]
] |
||
8a9q66 | how do fashion designers gain fame when they start out | How did fashion designers like Ralph Lauren and Yves saint Laurent gain fame when they started out? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8a9q66/eli5_how_do_fashion_designers_gain_fame_when_they/ | {
"a_id": [
"dwx5wya",
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"score": [
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11
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"text": [
"By being rich and spending lots of money around other rich people in places that are rich...\n\nYou see, the fashion industry is a sham. A showcase for the elites to flaunt their wealth with outlandish, impractical and exotic wares that are only desirable because they say so. ",
"You know how people always laugh at those really outlandish outfits at fashion shows that nobody would ever wear? That's how fashion designers get famous. They make unbelievable, over the top outfits to grab attention, then once they have it they use their renown to sell things people actually wear like jeans or t-shirts."
]
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[],
[]
] |
|
4jvv3k | how do cultures develop in the first place and what defines a culture? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4jvv3k/eli5_how_do_cultures_develop_in_the_first_place/ | {
"a_id": [
"d3a1kc4"
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"score": [
10
],
"text": [
"A little like evolution. Throw shit at a wall until something sticks.\n\nThe collective social practices, behaviour and etiquettes of a demographic."
]
} | [] | [] | [
[]
] |
||
k9091 | explain like i'm 5 how moisturizer works. | It kind of baffles me and I'm not convinced it does anything beneficial for your skin. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/k9091/explain_like_im_5_how_moisturizer_works/ | {
"a_id": [
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"text": [
"All it really does is make your skin LOOK better. Moisturizers make it easier for water to get into your skin, and it brings the water already in your skin to the surface so it looks pretty and feels soft. \nOnce you wash off the moisturizers though, they lose effect. Some stay behind, but if you stop using moisturizers (as with any other \"beauty\" product) you lose the results.",
"All it really does is make your skin LOOK better. Moisturizers make it easier for water to get into your skin, and it brings the water already in your skin to the surface so it looks pretty and feels soft. \nOnce you wash off the moisturizers though, they lose effect. Some stay behind, but if you stop using moisturizers (as with any other \"beauty\" product) you lose the results."
]
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[],
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] |
|
7twjfp | pros and cons of using an ionizer on an air purifier? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7twjfp/eli5_pros_and_cons_of_using_an_ionizer_on_an_air/ | {
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"text": [
"Charged particles in the air a) stick to things (like walls, upholstery, you) and also raise the static electricity level for the particles.\n\nIf the air is being ionized in too great a concentration, you also run the risk of that ionization hitting your lungs, causing those larger particles to lodge in your lungs instead of getting expelled again.\n\nSeems to methat a two-phase ionizer would fix this in a filtration system, but I've never heard of anyone doing that (applying electrons to the particles at the first filter, and then stripping electrons at the next)."
]
} | [] | [] | [
[]
] |
||
pkv94 | why youtube videos always seem to get stuck at 306 view count. | Is there a reason for this? 306 seems rather arbitrary. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/pkv94/eli5_why_youtube_videos_always_seem_to_get_stuck/ | {
"a_id": [
"c3q65nr"
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"score": [
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"text": [
"When a video is getting a lot of views in a short period of time (like right when someone popular uploads a video) it stops, the number they use is about 300, so when it gets to many views in that short period of time, youtube stops counting views for a bit, and makes sure all the views are from different people, and not bots or anything like that. This is to stop people from unfairly getting views on their video.\n\n**TL;DR** It is to check if the views are real people."
]
} | [] | [] | [
[]
] |
|
8ijnx1 | How does tidal heating work? | I was watching a video and someone said that some Jupiter's moons aren't as cold due to a process called tidal heating but didn't add much to it. Can someone explain because it sounds cool? | askscience | https://www.reddit.com/r/askscience/comments/8ijnx1/how_does_tidal_heating_work/ | {
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"text": [
"Think of the ebb and flow of the tides on Earth. These are caused by the gravitational pull of the moon, as well as the sun. Jupiter causes similar tidal movements of the masses of the moons orbiting it where the difference in gravitational pull on one side of the moon isn't the same as the force felt by the other. So, as the moon rotates and revolves around Jupiter they expand and contract from this change in the pull that different parts feel at different times.\n\nSo, the moons look like they are stretched slightly in the axis that points towards and away from Jupiter and are compressed on the sides pointed 90 degrees off from that line. Compression creates heat, expansion releases it. Rinse and repeat and the moons heat up while leaching a bit of angular momentum out of the whole system.",
"If you bend a paper clip back and forth, it will get hot. When outside forces irreversibly deform a material, energy is released as heat."
]
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[],
[]
] |
|
2e4c6j | [WW2] Are there any memoirs of the major figures on the German side worth reading? | I am quite interested in German perspectives on WW2. Especially the major participants and how they looked back on it - What were their thoughts on why they lost? What was it like on D-Day, how they reacted when they Dresden burned - that kind of thing.
Did the German generals of the WM leave many memoirs and are any particularly insightful?
Any recommendations very gratefully received. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2e4c6j/ww2_are_there_any_memoirs_of_the_major_figures_on/ | {
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"Hans Von Luck's *Panzer Commander* is a good read. It's not a complete whitewash of his role in WWII, but it *is* biased (as are most memoirs). He served in nearly every corner of the war. In particular, I found his post D-Day accounts to be compelling.",
"I think von Manstein and Guderian are worth a read. They are NOT unbiased though, and seek to place all blame for the war's military failures and atrocities on Hitler and the SS, and avoid any blame for themselves or the German Army and General Staff as institutions.",
"Rudolf Höss (the commandant of Auschwitz-Birkenau) wrote a patently self-serving autobiography before his trial. Although Höss comes across as a particularly loathsome individual, it's an important window into how some of those involved in Nazi genocide conceived of and presented themselves. Höss takes great pride on being an able administrator and the memoir has the gall at times to be self-pitying (he talks of salving his conscience by going on long horse-back rides in the Polish countryside). \n\nAs for German generals' memoirs, to paraphrase Gerhard Weinberg: their consistent mantra is \"if only the Führer had listened to me...\" but they never finish it with \"then the war would have lasted another three months and then the Americans would have dropped the atomic bomb on us.\"",
"Albert Speer's *\"Inside the Third Reich\"* is a very good look at the inner workings of Hitler's day-to-day, changing Nazi policy, and the German war machine/industry. \n\nHowever, it was written when he was imprisoned at Spandau, and while the facts are straight, his opinions and recountings of interactions should be taken with a grain of salt. Lots or credible historians are pretty sure he messed with some facts to paint himself in a better light. "
]
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|
7qxj5a | Do all neutrons have the same mass? | In chemistry today there was an example there was an example of a magnesium atom and 2 other isotopes, but the math didn't make sense because the only change should have been in neutrons adding roughly one more AMU but the change was different, from magnesium-24 to magnesium-25 was 1.0008 AMU and from magnesium-25 to magnesium-26 was about .9967 AMU. What can explain the difference? | askscience | https://www.reddit.com/r/askscience/comments/7qxj5a/do_all_neutrons_have_the_same_mass/ | {
"a_id": [
"dsso1xd"
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"text": [
"Every neutron is fundamentally identical to every other. So they all have exactly the same mass.\n\n > but the math didn't make sense because the only change should have been in neutrons adding roughly one more AMU but the change was different, from magnesium-24 to magnesium-25 was 1.0008 AMU and from magnesium-25 to magnesium-26 was about .9967 AMU. What can explain the difference?\n\nThe mass of a neutron is not exactly one AMU. Also, you're neglecting binding energies. So the difference will not be exactly 1 AMU."
]
} | [] | [] | [
[]
] |
|
16fhek | nasal congestion | So I have bronchitis right now, and as I'm laying in bed trying to fall asleep I have a few questions. I get the premise of why it happens, but I'm more asking about the plumbing I guess. Why is it that when I lay in a certain position it sometimes clears up? Why does that "specific position" change over the course of the day/night? Also, could someone direct me to a diagram of the sinuses and nasal canals? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/16fhek/eli5_nasal_congestion/ | {
"a_id": [
"c7vj7j1"
],
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"text": [
"The majority of nasal congestion is caused by swelling of blood vessels in your nasal passages. This expands the flesh and blocks off the airway. The reason it changes when you lie in different positions is that the blood will collect in your tissue based on gravity. The reason it changes over time is that there is a 2-3 hour nasal cycle where one nostril will swell while the other contracts and then reverses. This cycle is normal and happens even when you're not sick. You notice it more when you're sick though."
]
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[]
] |
|
7kmms8 | how can some countries that rely on resource extraction and agriculture, like australia for instance, be really rich, but others, like say zambia, be really poor? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7kmms8/eli5_how_can_some_countries_that_rely_on_resource/ | {
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"There is nothing inherently wrong with resource extraction and agriculture. Those things can be done efficiently or inefficiently. The nation of Rhodesia which changed its name to Zimbabwe, used to have very profitable farms which exported food and provided a basis of the national economy. However the farmers were white colonists so they had to go, and their farms were forcibly handed over to traditional subsistence farmers. As a result the economy of Zimbabwe was destroyed. Such is the legacy of the great and recently deposed Robert Mugabe.\n\nThe wealth of any nation depends first and foremost upon an educated population. If you do not have that, you have nothing.",
"It mostly has to do with who owns the resources and how the income is distributed. In some counties, the income goes to good wages and tax income that is employed t benefit the country. In other cases, the income is extracted by outside companies and/or funneled into accounts for the personal benefit of those in power.",
"There is no simple answer because every country is different. Let's look at the two countries you mentioned though. A few key differences right off the bat:\n\nZambia is landlocked, Australia isn't. That makes it a lot easier for Australia to get its goods to international markets.\n\nAdditionally, this means it loses out on having access to ocean based resources, something Australia makes a significant amount of profit from.\n\n_URL_0_\n\nZambia also has a significant AIDs crises going on, with roughly 17% of its adult population having HIV/AIDs, which comes with significant costs of its own.",
" > How can some countries that rely on resource extraction and agriculture, like Australia for instance, be really rich, but others, like say Zambia, be really poor?\n\nWhen you are considering something as complex as countries it is difficult to point at one thing to explain their relative economic states. However if you had to sum things up it would be this: Infrastructure.\n\nIt is one thing to have natural resources in a country and another thing entirely to be able to access them effectively. Suppose you can find a rich metal deposit in Zambia and want to start a mine. What do you need?\n\nYou are going to need mining equipment, basically all of which you will be able to source from outside the country. No problems there. But when that equipment arrives it will be on a boat and they can't very well just push hundreds of tons of mining equipment off the boat onto a beach. You will need a fairly well equipped port to offload the cargo. Then you will need vehicles to transport that equipment over roads... oh, you also need a network of high quality roads going everywhere you need to travel! Not only will you need them to get your equipment in but you will need them to carry what you mine out. In fact you probably need roads as well as a rail network for the inexpensive movement of heavy cargo both to and from those ports. And let us not forget that Zambia is land locked so those roads and rail networks are going to need to pass through Mozambique, Tanzania, or Angola with the ports in one or more of those countries.\n\nYou are also going to need utilities such as electricity and water. Did you plan to build a power plant and water purification plant as part of your mining operation? Well you probably need to because those certainly aren't available either. With all that you still need workers for your mine; trained workers capable of operating your expensive heavy machinery, not spear-wielding tribal natives. You could eventually educate them of course but now what are you doing, building schools? Where do your workers live, what do they eat, where do they obtain their various necessities? You need hotels, apartments, restaurants, convenience stores, shopping malls, clinics and hospitals, mechanics, banks, etc.!\n\nYou just wanted a mine and you have to build an entire city out of nothing! And what precisely are you going to get out of this enormous effort? The natives are going to want to govern themselves of course, and there is a good chance you are going to be called out for colonialism when the workers are paying to live in your hotels, eat from your restaurants, buy goods from your stores, electricity from your power plant, water from your purification facility, drive on your roads, etc. Might they rebel and seize all that stuff for themselves, stealing your mine and infrastructure for their own use? Of course they would, of course they **did**!\n\nSo outside investors look at such situations and say \"Fuck that!\" which leaves the locals to figure all that out themselves while their politicians nearly universally are corrupt and fleecing what wealth exists from the continent."
]
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[],
[],
[
"http://theconversation.com/fishing-is-worth-more-than-jobs-and-profits-to-australias-coastal-towns-67053"
],
[]
] |
||
582oa3 | Why do lasers have such a visible diffraction pattern? | When looking at a laser hitting a surface, whats the cause of the obvious diffusion pattern from it?
Its almost like being able to see each individual photon beam. | askscience | https://www.reddit.com/r/askscience/comments/582oa3/why_do_lasers_have_such_a_visible_diffraction/ | {
"a_id": [
"d8x7hin"
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"text": [
"Do you mean like [this](_URL_0_)?\n\nThat pattern is called \"[speckle](_URL_1_).\" It occurs because light from each point on the surface travels a slightly different distance to reach your retina, and then interferes there. Normal (fluorescent, incandescent) light doesn't do that because it's not [coherent](_URL_2_).\n\nSince this pattern occurs on your retina (and not on the surface), it doesn't go away if the surface is out of focus. You can [use speckle to determine](_URL_3_) whether you're near-sighted or far-sighted by moving your head left and right. If the speckle moves the same direction as your head, you're near-sighted. If reversed, you're far-sighted."
]
} | [] | [] | [
[
"https://upload.wikimedia.org/wikipedia/commons/1/19/Objective_speckle.jpg",
"https://en.wikipedia.org/wiki/Speckle_pattern",
"https://en.wikipedia.org/wiki/Coherence_(physics\\)",
"https://en.wikipedia.org/wiki/Eye_testing_using_speckle"
]
] |
|
bw406y | when suspects are being interviewed, why are they advised by their lawyer to say “no comment”? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bw406y/eli5_when_suspects_are_being_interviewed_why_are/ | {
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"Literally anything you say can be used against you. You wont help yourself by speaking to the police in any way.",
"You have the right to remain silent. Anything you do say can be used in evidence. Evidence against you, that is.",
"As a defense attorney, I advise my clients only to speak to cops 1) if I’m in the room, and 2) if there’s an agreement for us to get something beneficial out of it.\n\nDetectives are trained interrogators and are often very good at twisting a person’s words. Plus, the burden of proof is on the State, so why potentially help them do their job (which is ultimately trying to convict you of a crime)."
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cn30wo | what does statistically significant mean? | If the p < 0.05, what does this mean?!
For some reason I just cannot understand this concept. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cn30wo/eli5_what_does_statistically_significant_mean/ | {
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"Go get a coin. Flip it a few times. Imagine that it comes up tails three times in a row. You cannot say, from your test, that the coin will always come up tails, because your sample size is too small. Your three coin flips are not statistically significant; your sample size is too small. That's one simple example. Now flip the coin a thousand times. You get 501 heads, 499 tails. The deviation is not statistically significant because the deviation from the predicted result is too small. If you got 999 heads and 1 tail, that would be statistically significant. The idea that p < 0.05 makes results statistically significant is actually a bit controversial, so don't take it as gospel.",
"It means \"it's very unlikely this happened by chance\".\n\nTake a coin, and throw it into the air. It can either land heads or tails. If it's a fair coin, the probabilities are 50/50. Half the time it's going to be heads, half tails.\n\nHow likely are you to get heads twice in a row? 0.5 * 0.5 = 25%\n\nHow likely are you to get heads 3 times in a row? 0.5 * 0.5 * 0.5 = 12.5%\n\nAt some fuzzy point that's really quite arbitrary we just decide \"Well, it's came up heads 100 times in a row. That's very, very unlikely to happen by chance, so it must be that the coin is rigged to fall on heads\".\n\nThe \"p < 0.05\" is just a way to say \"the probability of this happening by chance is below 5%\", and somebody decided that a 5% risk of being wrong because things happened to align just right is acceptable.",
"Let's say you want to study if men and women have the same average height (we know the answer, but it is just an example). You measure the height of 10 men and 10 women and calculate the average.\n\nIn general your averages won't be the same even if men and women have the same average height. You might have picked a few very tall men, or got some very small women, or whatever. If you see a difference, how do you know if it is an actual difference between the groups and not just a random fluctuation in your study?\n\nYou calculate \"how likely am I to see a difference at least as large as observed *if the average height is the same*\". This is called a p-value. If that result is something like 60% (p=0.6) then your study is not conclusive. The difference you see might be real but it could also just have been random chance. If the answer is 10%, it is still quite possible that it was random chance without a real effect behind it. If the answer is 0.00000001%, then you are quite confident that the averages are indeed different.\n\nWhat people should do: Just give the observed difference and the expected amount of random fluctuation, leave the interpretation to others.\n\nWhat is often done, unfortunately: People look if that chance is below 5%, and if yes claim there would be a real effect and call it p < 0.05.\n\nThere are a few problems with that approach. One is publication bias: If you find something where you can calculate p < 0.05 then you are more likely to get the result published. But we know p < 0.05 happens by chance with 5% probability even if there is no real effect. So you don't just publish about things that are real, you also publish 5% of all other things and falsely claim they would be real.\n\nIt gets even worse: Typically studies don't start with a single question (like the height difference between men and women). If you also record the age of people you can look for a height difference in many different age groups. Record their favorite color and you can look if there is a height difference only for people loving blue, or red, or whatever. Each of these options has a 5% risk to be falsely claimed as significant difference. Look in enough places and you are guaranteed to find a few of these, even if there is no real difference. [Here is a comic illustrating this](_URL_0_).",
"Means: less than 1 in 20 (5%) odds that I'm mistaken in this assumption.\n\nBecause coincidences DO happen, you can never be completely certain.\n\nBut statistics and probabilities do have this built in:\n\nOut of 100 research pieces you see, with that p < 0,05, you would get 95-96 right, but you'd expect some 4-5 of them to be wrong. And you don't know which.",
"This following answer isn't really ELI5 but I've tried to keep with the spirit of it because to be honest, just looking at the responses here, clearly there are a lot of people there who think they know what a p-value is, but don't actually.\n\nThis 'p < 0.05' thing comes up in an area of statistics called *hypothesis testing*. For instance, when you flip a coin, the probability of heads should be 0.5 (if the coin is fair). But we may have flipped a coin 1,000 times and only got 20 heads. So we ask ourselves, \"Is it true that the actual probability is 0.5? Is my coin fair?\"\n\nWe would expect that the coin is fair, so the probability of heads is 0.5 (or 50%). This is called the *null hypothesis*. It is what we will test against. We are saying here that **if the null hypothesis is true**, the fact that we got 20 heads out of 1,000 trials is just because of probability and chance. Further, if we flipped the coin 1,000 times more we'd probably get closer to 500 heads. If we actually got 502, no biggie, because that's just probability and chance at work anyway. Again, assuming the null hypothesis is true (that is, the coin is fair).\n\nThis belief we have (i.e. the null hypothesis) seems quite logical to us, so we want only very, very good evidence to reject it. What is our evidence?\n\nWe construct what is called a *test statistic*, which (skipping some statistics) allows us to compare our hypothesised probability of heads (0.5) with our observed probability of heads (0.02 after 1,000 trials). Now, **if the coin is fair** (i.e. the null hypothesis is true), the probability that we flip a coin a 1,000 times and get 20 heads **or less** has probability *p,* which is called the p-value.\n\nNow, at what level do we want to chop it off? By convention, if our observed result (or worse) has less than 5% chance of happening (i.e. p < 0.05), then we will reject the null hypothesis because our observed result is *statistically significant*. What does this mean for us? It means we *reject* the null hypothesis. In our example, we say, \"This coin is biased. It is an unfair coin.\"\n\nAs an example: if we actually conducted the test I mentioned above, **if the coin was fair**, the probability we would get 20 heads **or less** after 1,000 trials is around 0.000001. Hence, our p-value is 0.000001 < 0.05, hence it is *statistically significant*.",
"This is a difficult concept to explain simply but it goes something like this.\n\nLet's say you want to know if carrots cause weight loss. One way you might test this is by sorting people into two groups, where one group eats their normal diet with carrots and the other without. Then after so much time, you measure how much the people's weights have changed.\n\nYou'll get some average change in weight between these two groups and statistical analysis shows p < 0.05. The thing is, you don't really know if it was carrots that caused the weight loss and it could just be random chance. Maybe the people who ate carrots had otherwise healthier diets, had a more active lifestyle, or a million other factors. \n\nWhat p means is that, *if the results were distributed* ***randomly*** *between the two groups*, then the results you observed had a less than 5% chance to appear. As this is such a low chance you can say with some certainty that the results weren't random and that carrots did indeed have some effect. However, your results may still be affected by chance, which is why the lower p is the more certain you can be.\n\nIf you want a clear explanation, I recommend [this video](_URL_0_).\n\nHope this helps!"
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bk25ay | what’s the difference between a bionic human and a cyborg? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bk25ay/eli5_whats_the_difference_between_a_bionic_human/ | {
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"It depends on the work of fiction you're referring to, but generally:\n From Wikipedia\n\n > The term cyborg is not the same thing as bionic, biorobot or android; it applies to an organism that has restored function or enhanced abilities due to the integration of some artificial component or technology that relies on some sort of feedback.[\n\nBasically what this means is that a cyborg is part machine, and the machine influences the organism's behavior, as well as responds to it.\n\nThink of the Borg in Star trek. Biological and mechanical components, but the mechanical components dictate the individuals actions.\n\nAs far as bionics, imagine you lose an arm, and replace it with a machine arm that responds to your neural impulses. That machine arm isnt influencing you're behavior, it's a slave to your will. If you replace every piece of yourself with machine components, those components don't influence you"
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xp1ft | Is there a way for humans to gather information faster than reading? | With the advent of the internet and smartphones, we have access to an enormous amount of information. But with our fast-paced fun-filled lives, we don't seem to have the time to research everything we'd like to learn about.
Has anyone heard of a device or technology that uses a different sense, outside of sight and sounds, that allows a faster 'download' of information? | askscience | http://www.reddit.com/r/askscience/comments/xp1ft/is_there_a_way_for_humans_to_gather_information/ | {
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"Interesting question.. But I guess it depends on what you define \"learning\" as. Reading is simply using our sense of vision to recognize symbols and lines on a page, and our brain applies meaning to them.\n\nYou could say that we \"learn\" not to touch a hot stove because after touching it once, our sense of touch tells our brain to pull back and we feel pain, and therefore have learned (hopefully) not to do it again. And that all happens much faster than reading does.\n\nBut yeah, I totally wish I could learn kung fu by plugging in a cable into the back of my head too man.",
"Sight allows for amazingly fast transfer of information if it's formatted correctly. Two-dimensional data is particularly easy to transfer in the form of graphs and charts. However, procedural knowledge is limited in transfer rate (actually limited to a speed much slower than typical reading speed) due to the increased amount of processing required. ",
"Information is useless if not thought about.",
"Is braille faster than reading?",
"Drugs such as ratalin? ",
"I've actually thought about this a lot recently. Just to clear something up, because some people seem confused about the question (let me know if I too misunderstood), you're asking what the fasted method of interpreting information is. Audio has to be fairly slow to be understandable, and there is a certain limit one's own reading speed, so you're wondering if there is a theoretical more *direct* means of communication of information, such as touch stimulation, smell, direct electrical communication to the brain, and so on. \n\nI hope my rewording helps, at least you'll know someone else has thought about the idea, too.",
"You might be interested in \"Decoded Neurofeedback\". Straight upfront; I don't know much about this field, nor I don't know how much headway has been being made in it recently.\n\nThat said, the basic premise is to upload skills directly into an individual's visual cortex using FRMI. As I understand it, if this works it would essentially provide the ability to copy skills from one individual to another.\n\nThere has apparently been at least one experiment showing promising results by Boston University.\n\nHere is a wikipedia link:\n_URL_0_\n\nAlso, no, the irony that this uses the visual cortex is not lost on me.",
"I do believe verbal learning is accomplished at a much higher rate when with someone of superior knowledge (in the field of interest) present. The ability to question rather than self-reason through difficulties in understanding is much more direct, while this may be deprecatory to true understanding however. \n\nI vacillate on the issue. Sometimes it seems that way, on more complicated things it may go the other way - you must understand the groundwork. \n\nBut certainly, it is easier for me to ask someone how to do a particular MATLAB operation than to read about it. And it is also certain that if I need to design a complicated device it is easier (also less stressful) if left to my own devices, and read about anything I need to know along the way.\n\nAll about efficacy. "
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2suary | Why have popular antibacterial soaps gone away from triclosan, and now use benzalkonium chloride? | I just noticed at the market the other day while in the soap aisle that all the major brands have switched over.
What's going on with that? | askscience | http://www.reddit.com/r/askscience/comments/2suary/why_have_popular_antibacterial_soaps_gone_away/ | {
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"Apparently studies have suggested it's linked to cancer and liver toxicity. The FDA still maintains that it's not harmful, however. \n\nI read in one study it did not cause cancer in mice, but in mice that they introduced cancer to, it caused progression of the cancer. \n\nMost likely people are buying less products with the ingredient, causing companies to lose money, and so I would imagine they're changing the formula. Just a guess though. \n\nEdit to say apparently it's been banned in MN. ",
"There have been worries about triclosan bioaccumulating and having possible endocrine effects, in addition to its antibacterial actions. And it's not wildly effective at that - regular soap without it seems about as effective. In light of this, the FDA has issued a draft rule revoking its GRAS regulatory status (\"Generally Regarded As Safe\"), which means that anyone who wants to use it would have to conduct a whole series of new studies to get it re-approved."
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19aw41 | Can someone please explain why Methenol poisoning can be counteracted with Ethenol? | askscience | http://www.reddit.com/r/askscience/comments/19aw41/can_someone_please_explain_why_methenol_poisoning/ | {
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"There was a [similar question a while ago](_URL_1_) - though it addresses antifreeze poisoning, the mechanisms are pretty much the same for methanol poisoning:\n\nAntifreeze poisoning is due to the [ethylene glycol](_URL_2_) in it. Ethylene glycol by itself is not intrinsically toxic (and in fact has a rather sweet taste). However, it can be metabolized into glycolate, glyoxylate, and oxalate, which can cause organ damage (particularly to the kidneys) as well as lead to a [metabolic acidosis](_URL_3_). One way to treat these problems is to decrease the rate of metabolism into the toxic end-products. [Ethanol is a competitive inhibitor of the enzyme](_URL_2__poisoning#Treatment) (alcohol dehydrogenase), so giving alcohol can decrease the rate of formation of toxic compounds. However, giving alcohol is associated with a number of logistical issues, so other compounds like [fomepizole](_URL_0_) are preferred (in humans at least). (A target goal of concentration around 22mmol/L or 0.1BAC is usually recommended.) Patients given alcohol dehydrogenase inhibition therapy should also be given cofactor supplements like folic acid, leukovorin, and thiamine. Other aspects of treatment include giving sodium bicarbonate to counter the acidosis, as well as dialysis to remove the toxic compounds from the blood. \n\n(Methanol poisoning is treated similarly due to similar pathways/mechanisms.)"
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9uo10s | america's midterm election? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9uo10s/eli5_americas_midterm_election/ | {
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"Every two years, the entire House of Representatives and 1/3 of the Senate is up for election.\n\nIn addition, states and cities/counties hold elections every year or multiple of years to fill state legislature/executive/judicial/miscellaneous spots and ask referendums questions.",
"This is what as known as a Midterm election, because it falls in the middle of the President’s term.\n\nAll 435 seats in the lower house of Congress, the House of Representatives, are up for election.\n\n1/3 of the seats in the upper house of Congress, the Senate, are up for election. \n\nIn the States, Governorships and State Legislature seats are up for election as well.\n\n",
"Presidents get elected to 4 year terms, so their election is a Presidential election.\n\nSenators get elected to staggered 6 year terms, so 1/3 are up for election every 2 years.\n\nRepresentatives get elected every 2 years.\n\nSo in a midterm election is a non-Presidential election, that occurs 2 years before or after a Presidential election. All Representatives and 1/3 of Senators are up for election."
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66nh3d | why would intel be interested in making "inferior" 14nm chips, if qualcomm has apparently been making 10nm chips? | Seems like Intel would want to get more transistors on a chip the same size. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66nh3d/eli5_why_would_intel_be_interested_in_making/ | {
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"Intel can make 10nm chips. Setting up a new fab is expensive so they have to sell something on the old process before they retire it and spend a billing dollars refitting the fab. Desktop and server chips are high margin parts so they get the new process. Mobile chips get the hand-me-downs."
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2btk3r | What was Saddam Hussein's game plan for holding and controlling Kuwait and what was his justification for invading in the first place? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2btk3r/what_was_saddam_husseins_game_plan_for_holding/ | {
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"In Saddam's words, after Iran-Iraq War he believed that oil prices were low, and this was due to Kuwait. He also accused Kuwait of slant-drilling (drilling at an angle from Kuwait into Iraq), thereby stealing Iraq's oil.\n\nAfter Iran-Iraq War, Iraq owed the Gulf Coast and Arabian Peninsula countries quite a bit of money, and he needed more money to rebuild his country. Saddam believed that these payments should have been/were gifts since Saddam fought against revolutionary Iran (as a bulwark, if you will). \n\nHe also believed that Kuwait and others were planning on invading him since he was weak due to losses sustained in the war. He thought this due to CENTCOM commander and staff visiting countries in the Arabian Peninsula (namely Kuwait). Saddam also believed that Kuwait was weak, and since no defensive preparations existed, that either they weren't completed or CENTCOM planning was offensive in nature.\n\nRegarding drilling, Kuwait also refused to go along with OPEC's pricing scheme to raise oil from $7/bbl to something akin to 25-50/bbl (for reference, oil has been around 80-120/bbl depending on type for last few years).\n\nLastly, his stated reason was to make Kuwait 19th province of Iraq called Kadhima (the area's name in the 18th-19th centuries under Ottoman rule), and to get rid of Emir of Kuwait and give people chance to choose own PM, gov't officials. \n\n\nSource: US interviews with Saddam Hussein after his capture in 2003. ",
"The lynchpin to Saddam's strategy for holding onto Kuwait rested upon his very skewed understanding of global politics and where Iraq stood within the international community. Iraq had garnered economic and military support from the various Gulf states during the Iran-Iraq War (for example, the Iraq Air Force had some dispersal airbases around the Gulf) and Saddam conflated this soft support with actual diplomatic strength. In 1989, the Saudis signed a non-aggression and military assistance pact with Iraq, and Saddam misconstrued as tacit Saudi approval of isolating Kuwait. He believed that since Iraq had protected the region from Iran, it would accept the price by acquiescing to the conquest of Kuwait. As Saddam explained to the Yemeni president in August 1990:\n\n > Iraq…who defends them [the Arabs] for ten years [and] they consider his defense as a liability against [Iraq]?…The time has come for every person to say…I’m Arabian…I’m Saddam Hussein…[If] Iraq will pay this amount of money to develop the Arab nation and to defend it [then] the other Arab countries must pay this amount of money…if they don’t we will fight them. \n\nSaddam had hoped that overtures to various Gulf states would fracture any attempt by the Saudis and exile Kuwaitis to form a response against his invasion. Although there was some validity to this assessment of Arab unity, Saddam woefully underestimated the fact that his use of armed force to resolve differences with Kuwait unified political opinion against him within the region.\n\nFurther afield, Saddam also did not understand the geopolitical changes that happened in 1989. In November 1990, his foreign Minister Tariq Aziz gave him optimistic reports that Gorbachev was not in favor of military action and would act to restrain the Americans:\n\n > as I have shared my opinion with you, deducing that the Soviet Union has no interest in a war of this manner happening and at this large scale. Maybe at the beginning and at different intervals the idea of a surgical [military] operation came up. [T]o hit Iraq and force it to withdraw from Kuwait, as maybe a disciplinary move for Iraq; it possibly entered their mind, but when they saw the reality and the fact that the Iraqi power was not something they could control in days or weeks and that this war will lead to major destruction in the region and to political and economic imbalance;\nand because the Soviet Union is worried about Europe and has\ninternal problems, sir, they couldn’t imagine that the situation would explode in the Middle East, seeing that it is their southern border. If a war of this manner happens the situation will explode, the Islamic factor, the nationalistic factor, the oil, and security all these would explode….and as Primakov said to you when you met, after you told him that we would hit Israel, that that was a nightmare they didn’t want to see…[A] nightmare to the Soviet Union, not out of love or care for us, but a nightmare.\n\nAdditionally, Saddam hoped that France, which had developed economic and military ties to Iraq, would also break apart the Coalition. Both of these estimates were off base. Although the USSR was not happy about Gulf War, it was more preoccupied with the domestic turmoil that was precipitating its breakup. A foreign intervention in the Middle East was the last thing Gorbachev needed, especially after the Afghanistan debacle. Aziz played up Mitterrand's ambiguous statements about the invasion and claimed that France would not jeopardize its domestic tranquility because of its large Muslim population. Attempting to use the French to split the Coalition had the opposite effect and the French behaved in a much more hardline fashion. In some ways, Saddam learned the wrong lesson from the fall of the Berlin wall; it made him feel that the age of the Superpowers was ending when instead it was leaving the US much greater latitude to act. \n\nIn short, Saddam believed that if he occupied Kuwait, it would be a diplomatic and military fait acompli. Iraqi strategy was that by turning Kuwait into a large fortified area, the Coalition would naturally fracture and Iraq's occupation would be assured. In a ministerial conference of August 1990, he said:\n\n > [W]e should focus on the historical event, such as the war between France and Germany in 1870 and during the First World War when France retrieved the Alsace Lorraine region and kept it united under regional policy laws, municipal laws, and autonomy after the First World War. France gradually extended its authority to this region until it became internationally and constitutionally part of France.\n\nIn hindsight, Saddam was naive and possessed a highly mistaken grasp of foreign affairs. \n\n*Sources*\n\nSassoon, Joseph. *Saddam Hussein's Ba'th Party: Inside an Authoritarian Regime*. Cambridge: Cambridge University Press, 2011. \n\nWoods, Kevin M. *Iraqi Perspectives Project Phase II. Um Al-Ma'arik (The Mother of All Battles): Operational and Strategic Insights from an Iraqi Perspective, Volume 1* (Revised May 2008). Ft. Belvoir: Defense Technical Information Center, 2008. < _URL_0_;. \n\n "
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140oq2 | what does it mean for a sports game to be 'blacked out'? | How come channels such as ESPN or CBS often has both college and professional sports games 'blacked out' in certain areas? Why do they do this and why is it sometimes only blacked out in certain areas (i.e.- the East/West coast or a specific state)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/140oq2/what_does_it_mean_for_a_sports_game_to_be_blacked/ | {
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"The NFL has a policy that says that if a home game is not sold out within 72 hours of kickoff, no channel which broadcasts less than 75 miles from the stadium can show the game. It's to force people to either shell for tickets to the game, or for cable (both of which the NFL makes money on).\n\n",
"It's usually because another network owns the broadcasting rights for that market. For example, ESPN may pick up a Phillies - Red Sox game for \"Wednesday Night Baseball\" and broadcast it nationally. However, the Phillies and Red Sox both have local cable channels that own the rights to all games in the local market. So ESPN is not allowed to broadcast the game in either Philadelphia or Boston. So everywhere else in the country you can watch the game on ESPN, but in Philadelphia and Boston the game will be on the respective local network. "
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67ilrg | In layman's terms, what does it mean to take a partial derivative of something? What does this accomplish? | [deleted] | askscience | https://www.reddit.com/r/askscience/comments/67ilrg/in_laymans_terms_what_does_it_mean_to_take_a/ | {
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"If you have a function which depends on multiple variables, maybe you'd like to know how the function changes when *one* of the variables is changed a little bit, but the others are all left the same.\n\nThat's what a partial derivative is.",
"It does the same thing as a regular derivative: the rate of change of a function as one variable changes (while keeping the other variables constant). \n\nIt accomplishes finding the rate of change of a function as only one of its variable changes.\n\nIf you are wondering about applications, there are many. You can use it to find the rate of change when you only care about one of the variables. Or to propagate uncertainty or error in a calculation (i.e. \"what's my error margin for the area of this cone if I measured the radius and height with a ruler that has a 1mm resolution?\"). Or to find the \"direction\" of maximum change of a function (maybe for optimization purposes). ",
"Imagine 3 dimensional space. OK, good, you're living in it, that should make this easier. OK, now imagine a simple sheet of paper, start off with the paper flat but then tip the long dimension up at a bit of an angle. The angle of the paper along the length is more than zero, but the angle of the paper along its width is zero. If the vertical dimension is z, and the horizontal dimensions are y for length and x for width then you have two interesting partial derivatives: ∂z/∂x (variation of height relative to width) and ∂z/dy (variation of height relative to length), in this case the first is 0 (the paper isn't tilted width-wise) and the second is a constant number across the surface of the paper, with a value corresponding to the amount of tilt. If it's tilted one way that number would be positive (if height increases with increasing y) or negative if it was tilted the other way.\n\nIn other words, partial derivatives are like taking a slice through a multi-dimensional function. Which makes it possible to characterize the overall function by just considering various slices.",
"You are on a hill at a crossroad. The South-North road goes uphill, at a rate of 2 feet per 100 feet, or 2%. The East-West road goes slightly downhill, at a rate of 1 feet per 100 feet, or -1%. These rates are also known as elevation grades. In math they are known as partial derivatives. "
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2dojxd | how do signatures hold up in court? | Like, idk about you guys but my signature changes all the time (sometimes I just make the letters different and shit) and I don't think it would be possibly to 'verify' one of my sigs by comparing it others. So how do signatures (let's say on a contract or something) hold up in court? Couldn't you just deny it if you signed anything and claim you never signed it? How would they prove that you did?
TL;DR why do signatures mean anything when you can't really prove that someone actually signed something without playing he said/she said | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2dojxd/eli5_how_do_signatures_hold_up_in_court/ | {
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"Cause you'd be lying under oath if you said you didnt sign it. \n\nWhat's to prevent you from doing that? Nothing. Just consequences",
"The purpose of a signature is to prove that someone physically interacted with a legal document. Imagine walking around with a contract to sell a baseball for $1000. You walk up to each person and ask them, \"Will you buy a baseball for $1000?\" and you show them the contract. Suddenly, one of them says, \"Sure!\" \n\nLater, that person decides they don't want to pay you $1000 for your baseball. So you take them to court and you tell the judge, \"See? This is the contract I showed them and that they agreed to.\" From the judges standpoint, there's not much that makes your interaction with the guy who said \"yes\" different than all the random people who turned you down.\n\nIn other words, a signature is just a way to show that someone was consciously aware that they were entering into an agreement... and they show that awareness by making a mark on the document.\n\nAnd that's a big point to this too: It just needs to be a mark. I can agree to a contract with a simple swipe of a pencil... and so-long as I intended that swipe to be my signature, then it is my signature. \n\nWhen it comes to \"proving it,\" this opens a can of worms. Perjury (lying under oath) is a serious offense with serious consequences. If I decide to back out of paying you $1,000 for a ball after I signed a contract that I'd buy it... it isn't worth $1,000 to risk lying, especially since circumstantial evidence can be used to prove it was, in fact, my signature or that I signed it.\n\nWhen the amount of money makes it worth it to some people to lie, then forensic analysts may be called in to check the signature for authenticity. In these situations, it is worth it to require more than just a signature from the opposing party. It's why there is so much paperwork for big deals... you're trying to make layers of redundancy to show that everyone is in agreement and reduce any chances that someone tries to act like they never agreed to the contract."
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2n226e | Do Millipedes/Centipedes have the same number of legs for life? Do they grow more? | Curious, couldn't find an answer on google search. | askscience | http://www.reddit.com/r/askscience/comments/2n226e/do_millipedescentipedes_have_the_same_number_of/ | {
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"Millipedes add segments with each molt until they reach adulthood, though even then some species continue to molt. Juveniles for the species studied in the source paper (Pseudopolydesmus pinetorum) molted 7 times before maturity, increasing their number of segments, legs, and overall length with each molt: they started with 3 pairs of legs on 7 segments and reached maturity with 31 leg pairs on 20 segments. [Table](_URL_1_)\n\nSo they grow more legs and segments as they develop to maturity.\n\n[Source](_URL_0_)\n\nCool question! "
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3x70s8 | Why didn't Ming dynasty invade and conquer nearby empires such as Japan, Korea or Vietnam? | My question is that while numbers of historical empires such as the Imperial Britain or Ottomans were always seeking to expand their territory by conquering nearby empires, why didn't Ming dynasty, one of the most prosperous eras of medieval China, conquer nearby smaller empires? Very primitive question so would be keen to elaborate and clarify some parts.
Edit: all the answers were fascinating. Thank you so much! | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3x70s8/why_didnt_ming_dynasty_invade_and_conquer_nearby/ | {
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"First of all, a bit of clarification – the Ming waged several wars against Vietnam – whilst I’m not entirely qualified to write in depth about it, see the Ming–Hồ War and subsequent control of Vietnam by the Ming. To more directly answer your question, it can be conversely asked, why would they invade and conquer their surrounding neighbours?\n\nThrough sheer lack of necessity, through the acceptance (or rather, for lack of a better word, integration) of other cultures by bringing them into the fold of Chinese culture, or simply through the Mandate of Heaven and traditional values that laid the foundation of solidarity in Chinese administration, the empire was able to maintain its basic outline and structure despite many shifts in government rule. Being ruled by different ethnicities (the Han of the Song dynasty, the Mongols in the Yuan, then the Han again in the Ming, and then later the Manchus of the Qing) surely didn’t help in cementing their power amongst the Asian region, and yet somehow it did. The spread of Chinese culture, the sinicisation process, and a significant number of court administrators were core to the preservation of a rather contiguous civilisation, and in a way, answers your question. By establishing common ground with the ‘barbarians’ bordering China to the north and west, as well as giving an impressive display of solidarity and power to other kingdoms, China was engaged in a peaceful tributary system with its neighbours. The benefits are quite clear – a source of income and supply without dedicating large amounts of resources and time (not to mention the destruction of lands) in having to physically invade, conquer, and pacify smaller empires.\n\nAlready this stands in stark contrast to the situations that both the Ottoman and British Empires faced, whereby unlike China they were either unable to maintain unbroken peace or otherwise faced a pressing need to expand. To touch on the first point on maintain civil order – the bureaucratic system of China (despite, yes, steering off that path as seen during the Three Kingdoms era) meant that officials and administrators were undeniably useful in allowing culture to spread, and thus via proxy, order and peace. Of course, asking why this didn’t happen in Europe opens you up to so many different reasons and what-ifs (which really would warrant another question on its own), but suffice to say that the same integration and ‘mixing’ of cultural values did not occur to as deep an extent in European/Near East civilisations as it did in China. \n\nThis also ties in to the need to expand as a way of securing the borders and preventing incursions of external powers – not to mention that the idea of simply invading another empire is somehow an easy task. Again, a hegemonic tributary system established by China was much more favourable, and this idea of not having to invade is compounded by the fact that, comparatively, China’s mainland was rich in resources – whether gathered through the assimilation of cultures or simply by virtue of geography, they had little need to actively look outwards for resources. This was also one of the reasons for the beginning of the Opium Wars and China’s insistence in not willing to trade substantial amounts of their own goods to the British for opium. Similarly, the expeditions of Zheng He served a very important role of both cementing the power and authority of Ming China as well as setting up and maintaining important tributes and monuments.\n\nWhilst the Ming didn’t invade and conquer many of its surrounding empires, it definitely did commit many resources to strengthening its northern frontiers against surrounding barbarians who, despite tributary relationships, were always a threat. Thus, through a combination of several factors such as that of administration systems, cultural and traditional values, and geographical necessity, the Ming did not actively seek to expand outwards as their European and Near East contemporaries would have. It would be important to note too that this systematic treatment of their neighbours is seen in varying degrees across many dynasties of China, and is not limited just to the Ming (although in many ways and at brief glance, it can be concluded that way). \n\nFor further reading specifically on the Ming, I’d recommend John Fairbank’s “China – A New History” (specifically chapter 6, on the Ming government), Jonathan Spence’s “The Search for Modern China” (specifically the first chapter on the Ming), and Patricia Ebrey’s “The Cambridge Illustrated History of China” (specifically the 7th chapter on the Ming). Outside the scope of the Ming dynasty, these books are still great introductions and reference books to China as a whole, and they should also be more than enough to answer most other questions you may have (and even give rise to some more questions).\n",
"I can provide some detail on the situation in Korea, which was being ruled by the Goryeo/Koryŏ dynasty when the Ming dynasty was founded in China. Goryeo officials were divided on whether to align themselves with the Yuan or the Ming. In 1388, a Goryeo expedition was sent to attack the Ming (*edited to remove the statement that this was to support the Yuan, since this was after the major Yuan-loyalist forces had already been defeated in the region*) in the Liaodong peninsula under the orders of a Yuan-aligned general. However, the Ming-aligned general who was commanding the force turned around at the border and returned to the capital to stage a coup, and in 1392 overthrew the Goryeo and himself became king of the new dynasty, Joseon/Chosŏn. So Joseon was from the beginning a friendly regime to the Ming, which recognized the Ming as the rightful ruler of China and were willing to play the part in the traditional tributary system of East Asia. For their part, the Ming, who were fighting Manchurian forces loyal to the Yuan, were in no position to make further enemies.\n\nGeography provides a large part of the explanation for why Chinese forces were never able to make lasting conquests in Korea (apart from short-lived commanderies in ancient times), let alone Japan. Korea is a rugged peninsula which will stretch the supply route of any invading force from China (as an example, a disastrous series of campaigns into Korea by the Sui dynasty of China in the 600s contributed to its demise). Even the Mongols needed 30 years to stamp out the last bit of resistance from Goryeo, which unlike China survived as a client state under Yuan overlordship. From the Yuan point of view, it was convenient to leave the Goryeo state intact as a regional counterweight to rival Mongol factions in Manchuria who could always threaten the central Yuan court.\n\nThis brings us to the fact that Manchuria, mostly populated by Jurchen tribes, served as a useful buffer between China and Korea. The Ming and Joseon could each expand their own borders at the expense of the Jurchens or vie for influence over the Jurchens without directly confronting each other. The Ming did eventually win overlordship over most of Manchuria (albeit briefly), but unlike the Yuan they never managed to incorporate it fully into the empire. The Jurchen chiefs, nominal vassals of the Ming, ran their own affairs in Manchuria. Eventually the Manchus, descended from a branch of the Jurchens, would establish the Qing and overthrow the Ming in China.\n\nJapan on the other hand was doubly protected from continental invasions by Korea and by the sea. The only time that continental forces were able to invade Japan was when the Mongols had finally pacified Korea, and the joint Yuan-Goryeo naval expedition to Japan was destroyed by *kamikaze*, the divine wind. The fact that the Mongols were bogged down in Korea for thirty years and had no experience in naval warfare to begin with saved Japan from the full brunt of the Mongol onslaught. Ryukyu was similarly protected by the sea.",
"From an economical standpoint, the Ming did not have the economic resources to sustain massive military expenditures needed for conquests. Owing to his background as a peasant, the Hongwu emperor set down the lowest land tax in Chinese history. In the early Ming, the land tax was 0.0335 *dan* (piculs) per *mu* (acreage).\n\nThe Ming collected tax revenue from a variety of sources - grain/rice, cloth, iron, tea, silk, etc., but the two biggest sources of revenue were the land tax (paid in grain) and the salt monopoly.\n\n*Da Ming Hui Dian* Wanli 7 (1578):\n\n* 16,201,436 registered households\n* 60,692,856 registered population \n* 26,692,642 *dan* of grain\n* 1,292,224 taels of silver from the salt monopoly\n* Average tax: 0.038 *dan* per *mu*\n\nIn 1522, 0.45 tael of silver was equivalent to one *dan* of grain, and in the Wanli reign, one tael of silver was around 2 *dan* of grain, so using that exchange rate, the combined income for grain and salt in 1578 would have been 14,638,546.5 taels of silver.\n\nI don't have the military figures for 1578, but in 1593, according to the *Hui Jilu* and *Wu Beizhi*:\n\n* 1) Liaodong: 83,324 soldiers\n* 2) Suzhou: 31,658 soldiers\n* 3) Yongping: 33,911 soldiers\n* 4) Miyun: 52,502 soldiers\n* 5) Changping:28,875 soldiers\n* 6) Yizhou: 34,697 soldiers\n* 7) Xuanfu: 78,924 soldiers\n* 8) Datong: 85,311 soldiers\n* 9) Shanxi: 51,764 soldiers\n* 10) Yantuo: 36,230 soldiers\n* 11) Ningxia: 27,773 soldiers\n* 12) Gansu: 46,901 soldiers\n* 13) Guyuan: 59,813 soldiers\n\n* Total: 651,665 soldiers with 279,158 horses, oxen, and camels\n* Expenditure: 7,154,630 taels of silver and 1,900,000 *dan* of grain.\n\n1,900,000 *dan* of grain equals roughly 900,000 taels of silver.\n\nSo if we assume that the revenue from grain and salt in 1593 was also somewhere around 15 million taels, that would mean **almost half of the Ming's revenue would be spent on maintaining the military *in peacetime*.** During wars, this figure would be even higher.\n\nIt is also important to keep in mind that tax revenues decreased over time for a variety of reasons. So the revenue figures you see here were much lower than during Yongle's reign, which was arguably the golden age of Ming military.\n\nObviously this is a very basic estimate, and I'm not counting other sources of revenue, but this should give you an idea of how expensive military upkeep was during the Ming and why they could not sustain prolonged periods of warfare. There were officials who opposed the Korean expedition in 1593 precisely because they were afraid of draining the treasury.\n\n**Edit 1**: The Ming's central treasury was known as the *Taicang* (the largest of several treasury vaults). Harry Miller's text *State Versus Gentry in Late Ming China* includes a table drawn from Chinese historians showing that that between the periods of 1587 to 1593, the *Taicang* had around 4 million taels of silver in revenue and 5 million taels of silver in expenditures, a deficit of nearly a million taels. James Tong estimates that from 1548 to 1617, between 60-80% of expenditures from the *Taicang* were military expenditures. \n"
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1wv7a0 | In the 1930s would most people in the western world have understood the concept of what a computer was suppose to be? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1wv7a0/in_the_1930s_would_most_people_in_the_western/ | {
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"In the 1930s, \"computer\" wasn't a thing, it was a job description. Insurance companies and banks employed thousands of people wielding mechanical calculators to balance spreadsheets and do what we take for granted with a single computer.\n\nIn the second half of the decade, a handful of the world's best minds (Konrad Zuse, Alan Turing, Howard Aiken) were designing electromechanical calculators, but the general public stayed ignorant. Things started to take off in 1939, and with the benefit of hindsight, it's fascinating to see what was being done. Bell Telephone was creating calculators for automatic telephone switching, universities were creating their own computing machines (University of Manchester, Iowa State University), and the World's Fair in New York gave inventors a chance to get publicity for their computing machines."
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35enqi | why don't developers in california, and other drought-stricken areas of the u.s., have to include solar panels and drought-resistant landscaping, as well as water-efficient appliances, in all new buildings? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/35enqi/eli5_why_dont_developers_in_california_and_other/ | {
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"Because they don't have to. France just made it a law that industrials area must have solar. Also, hiring a construction company to build a home actually doesn't cost that much, they certainly don't make a million off of building a family home.",
"Because the impact of requiring this for residential homes would be minimal at best. When it comes to the California water crisis, 80% of the water is used by agriculture. Residential buildings just don't have a big enough impact to warrant it. Additionally, measures like this would increase the house prices. House prices in California are already pretty high (in the most populated areas) which means you are not really going to have much support for a measure that increases the prices even more",
"Because the current way is cheaper. Not everyone can afford solar or to convert a yard that way.\n\nI'd agree with the landscaping, but solar like you said costs more which will likely price those houses out of their target market.\n\nDevelopers don't develop to be ecologically sound. They develop to turn a profit and keep their shareholders satisfied.\n\nSuch requirements would just be passed on to the initial purchaser, and 20k could easily keep someone from being able to close the deal.",
"Because this is America and we're supposed to assert dominance over nature in every way possible. Common sense be damned! ",
"Austin TX is the fastest growing city in America. Ideas like \"solar power on every house\" in California are a big reason why, and when those people move they bring a lot of tax money with them.\n\nGreen lawns for new buildings would be a good idea though, as long as it's just a matter of switching out plants and not spending $5,000 extra on a lawn or having 4 people approve a landscaping plan that takes 3 months. You can make your toilets use less water easily too. Just set the valve inside the bowl so less water loads up.",
"All states, not just CA, require low flow toilets on all new construction since 1992. CA just passed a law requiring low flow toilets to be installed with any remodeling job or sale of an older home effective Jan 1 2016.\n\n_URL_0_\n\nI cannot speak to the solar aspects but where I live, the cities themselves often run the utilities, and they would much rather continue to charge you $$$ every month than build in existing savings."
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1dfe90 | that jet of warm air as i walk into a shopping mall - what does it do? | So I want to enter the shopping mall complex for some nice air-conditioning, and this blast of hot air sweeps across me over my head as I walk past the entrance.
What merit is there to this great atrocity?
My friend tells me it kills bacteria, is this the truth? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1dfe90/eli5_that_jet_of_warm_air_as_i_walk_into_a/ | {
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"Your friend is full of crap.\n\nELI5: When they take warm air and make it cold, the heat has to go somewhere, so it goes out the vents. One of those is near the door where you walk in. At home you can try going outside and standing behind the air conditioner in the window. It's not as big and powerful as the grocery store AC but you will feel some heat there.",
"Keeps the bugs out",
"The jet of air is too stop the insects from flying inside the store, Making the store a nicer place to stop. (And you don't have a bunch of people running screaming BUGGGGSSSSS!!!) :P",
"I would suspect is also has to do with temperature differentials - less AC is going to escape the doors if there's a layer of hot air between the doors and outside.",
"[They're called \"air doors\" or \"air curtains\"](_URL_0_) and is turned on when an entrance/exit door is opened so it keeps bugs out. They can also be used to keep air from a building from escaping and save on heating and cooling costs.",
"Most comercial buildings have forced air towards the door to keep insects out. It is not air conditioning as the excess heat would escape on the roof where the a/c units are."
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xin9x | When and why did people stopped portraying Jesus as the Middle Eastern man that he was and started portraying him as we do today? | When and why [this](_URL_1_) turned into [this](_URL_2_)?
Also, when i was searching for those images of modern Jesus i found[ Cage Jesus](_URL_4_).
-----------------------------------------------------
[dogwillsit said:](_URL_0_)
> When: Probably when Jesus began being worshiped and depicted in art by people who looked more like the first image than the second image. So, probably 1st to 2nd century AD. An art historian can probably answer this way better.
[beancounter2885 said:](_URL_5_)
> Jesus is usually depicted as whatever race is prominent in the area where the depiction was made. Here's Han
> [Chinese Jesus](_URL_3_) . | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/xin9x/when_and_why_did_people_stopped_portraying_jesus/ | {
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"When: Probably when Jesus began being worshiped and depicted in art by people who looked more like the first image than the second image. So, probably 1st to 2nd century AD. An art historian can probably answer this way better.\nWhy: People relate more to people who look like them. Compare the second image of Jesus to images from Coptic and Abyssinian art.\n\nUpvote for Cage Jesus.",
"Jesus is usually depicted as whatever race is prominent in the area where the depiction was made. Here's [Han Chinese Jesus](_URL_0_).",
"The modern image we have of Jesus today is theorized to be based off of the Cesar Borgia, the son of Pope Alexander VI. Alexander was known to be one of the more nepotistic and heavy handed political popes of the time. \ne: [Just look for yourself](_URL_0_)",
"I found a [gallery of Christian Iconography](_URL_1_) from different places and times. Perhaps it can answer your question better.\n\nIt should be noted that images of Jesus and Mary differed from place to place; for example, the Virgin of Guadalupe is depicted with a brown skin. So basically, it's most about the place where the paintings were made.\n\nBut [there's a recent rumor](_URL_0_) (**which can't be verified**) about pope Alexander VI asking Leonardo to paint Jesus in the image of his son, Cesare Borgia (cue conspiracy theories about Leonardo and the shroud of Turin).\n\nEDIT: I just remember the story of [St. Margaret Mary](_URL_3_), to whom Jesus supposedly appeared and asked her to show the image of the \"Sacred Heart\" to spread his devotion. The Catholic Church is FILLED with these stories, like the one about Jesus appearing to [St. Faustina](_URL_2_) to spread the devotion of the [Divine Mercy](_URL_4_). How true are these stories? We really can't know.\n\nAnyway, given that most images of Jesus were made in Europe, expect him to be portrayed in the image of Europeans.",
"I just wrote out a super long response to this with links to examples and everything and my phone refreshed the page and my response was gone. The short answer is that Jesus has never been depicted as a Middle Eastern man in Western art. If anyone's interested in the long answer, I will retype it up later when I can get on my computer.",
"I've seen a blonde Jesus painting at a church in Denmark. I've heard Jesus is black in Africa.",
"Related question: what level of racial diversity would people around, say, ~1300 be exposed to? If I'm an artist and have only seen Italians, it would make sense to portray Jesus as Italian. Obviously cities would be a little more diverse, especially the more connected they are to trade routes.",
"From what I've heard, some of the earliest converts to Christianity were the barbarians attacking Rome. There are depictions/idols (yes, I know, false idols etc., but comparably we have the manger scene) of Jesus dual-wielding battle axes as some sort of European warrior god.\n\nJesus is/was as adaptable to local customs as needed to be to be accepted. So if you're asking if making his appearance match that of local flavor, that's not a recent development, no. To my knowledge, his accurate depiction as a middle eastern man in art is a relatively recent thing. \n\nA lot of lore about Jesus/the bible (such as the \"birthday,\" of Jesus, etc.) is mostly adapted to other cultures to fit in. I'm not a scholar on such matters, however, simply a historian who is admittedly way far from his period of concentration."
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"http://www.popularmechanics.com/cm/popularmechanics/images/QA/face-of-jesus-01-0312-mdn.jpg",
"http://www.indianinthemachine.com/sananda2.jpg",
"http://upload.wikimedia.org/wikipedia/commons/8/8a/ChineseJesus.jpg",
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"http://www.pallasweb.com/ikons/ikon-gallery.html",
"http://en.wikipedia.org/wiki/Mary_Faustina_Kowalska",
"http://en.wikipedia.org/wiki/Marguerite_Marie_Alacoque",
"http://en.wikipedia.org/wiki/Divine_Mercy_image"
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2fwmfy | i know stores can't legally stop shoplifters anymore, but seriously- why the hell don't they at least have someone standing at the door for appearances? | I'm a late 20's dude and to be honest, I never really gave a shit about shoplifting. I never did it, and while I heard stories, I never really saw it go down.
Well, I recently moved to California and damn, I see kids walking out of the grocery store with shit just about every damn time I'm there. I always see news stories about someone getting canned because they tried to stop a shoplifter, etc. etc. I get that for legal reasons, they can't.
But I'm curious, why not have someone if not just for appearance sake? Would it really cost that much more to pay that one person, than the store would lose without them?
Maybe so, but I'm asking this here in case the answer is more complex or perhaps not so cut and dry. Thanks for anyone's response, especially if you've worked in retail or grocery.
EDIT: I'd like to mention that I've seen a security guard type dude at the front door of Whole Foods Market (In Texas at least), so I know *some* companies seem to do this. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fwmfy/eli5_i_know_stores_cant_legally_stop_shoplifters/ | {
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"why cant they stop someone from shoplifting? That sounds really weird.",
"A lot of stores (Including the one I work in) have specially trained loss prevention agents. They are allowed to stop shoplifters. This is a full sized grocery store, it might not be cost effective for someone to do that at a convenience store or something, though.",
"Both of your premises are wrong. Detaining shoplifters varies by state, it's not illegal across the board. \n\nMany small stores don't bother with loss prevention because it isn't worth it. Hiring a full time guard costs money, so unless you're getting so much merchandise stolen that it outweighs the guard's salary, it's just throwing away money.\n\nMost of the bigger stores though *do* have either guards or undercover people who pretend to shop and look for thieves, who do approach shoplifters when they get caught. They usually try to keep things low key to avoid making a huge scene though, because that can get out of hand really quickly. "
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3qn17z | why were cigarettes the norm then and now are considered deadly? | When you watch old films, you see people smoking everywhere like it was healthy or something. You can even see it in advertisements and stuff. I want to know, why was it like normal then and no it's like a taboo to smoke? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qn17z/eli5_why_were_cigarettes_the_norm_then_and_now/ | {
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"Because there wasnt enough notable research to prove it was bad for you. Consider that in several years people will ask your question about something else.\n\nThe reason why not enough research was done was because people saw little need for it until people started getting lung diseases.",
"Several reasons.\n\n* We know a lot more about the health impact of tobacco than we did then. There's been tons and tons more scientific studies that link tobacco to harmful health effects than back in the 50's.\n\n* Cigarette companies actively worked to quash any links to their product and health concerns. They were very successful at manipulating the governments to protect themselves until things finally started to catch up with them a few decades ago and the general public realized they were selling poison.\n\n* Advertising standards were a lot more lax back then. [You could actually say stuff like \"4 out of 5 doctors recommend Lucky Strike cigarettes\".](_URL_0_) and get away with it.\n\nPeople more or less didn't care as much about antibacterial perfectly clean no-gluten households back then. Not everything, from playgrounds to cars, was as concentrated on being as safe as it is now. So cigarettes thrived.",
"Back then, doctors and scientists didn't know that smoking made you sick. And when they did find out, cigarette companies spent a lot of money in advertising to say it wasn't true. \n\nAlso, cigarette companies paid for a lot of advertising and \"product placement\" so cigarettes showed up everywhere. They even had TV shows that were sponsored by cigarette companies, like the Chesterfield Supper Club starring Perry Como. ",
"Consider this, heroin was first marketed as a cough suppressant. People didn't know shit about harmful effects back then."
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1r7mr2 | synchronous vs. asynchronous, in terms of ajax, ftp, etc. | I've got a very basic general knowledge of the internet, in that I know what clients and servers are, that different protocols (FTP, HTTP, etc) exist, and that data can be transmitted in different ways.
What I don't understand is the term *asynchronous*, as used in the acronym AJAX and so on. So I searched ELI5, and found these explanations:
> Synchronous is like going to the pizza place, making an order, waiting for the order, then taking your pizza and going home. Asynchronous is like calling the pizza place, saying "Hey, can I get a large pepperoni", then in 20 min a pizza shows up at your door.
So that makes sense, I suppose. In synchronous communication, every exchange between client and server happens in order, and the next one doesn't happen until one is completed. Right? But that doesn't explain, to me, why FTP is considered asynchronous. In FTP, aren't you constantly engaged in a conversation with the other side? Isn't that synchronous?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1r7mr2/eli5_synchronous_vs_asynchronous_in_terms_of_ajax/ | {
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12m0v6 | From what cup size on does a woman have more breast than brainvolume? | askscience | http://www.reddit.com/r/askscience/comments/12m0v6/from_what_cup_size_on_does_a_woman_have_more/ | {
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"You can get information on the [brain volume very easily](_URL_1_).\n\nBreast volume data, although I thought would be hard to find, was [almost as easy to obtain](_URL_0_).\n\n**For the lazy:**\n\nAverage woman brain size: ~ 1130 cm^3\n\nSize of breast that is 590 cm^3 : 40A, 38B, 36C, 34D, 32E, 30F and 28G. A **pair** of either of these would be the same volume as the average female brain.\n\nSize of breast that is 1180 cm^3 : 48A 46B 44C 42D 40E 38F 36G 34H 32I 30J 28K. **ONE** of these breasts would be the same volume as the average female brain.\n\n"
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ag21lm | how are combination and permuation different? | Ive looked it up and I still dont understand
The ones formatted like this
9c4 vs 9p4 | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ag21lm/eli5_how_are_combination_and_permuation_different/ | {
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"For the latter: different sets containing the same values picked, just arranged differently are treated as unique sets. \n\nFor combinations, they would be considered the same.\n\n\nIe: \"1 2 3\" and \"3 2 1\" (let's just say out of a set of the positive integers) would be considered the same combination but different permutations.",
"permutations care about order, combinations do not.\n\nSay for your example our nine choices are a, b, c, d, e, f, g, h, i.\n\n9p4 treats a,b,c,d differently from d,c,b,a.\n\nFor 9c4 we don't care about order, just whether we've seen that combination of letters yet, so a,b,c,d and d,c,b,a are the same thing."
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ftbcxc | how distilleries repurpose to make hand sanitizer? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ftbcxc/eli5_how_distilleries_repurpose_to_make_hand/ | {
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"Hand sanitizer is 70% alcohol (140 proof). The other 30% is water and thickening agents. Distilleries have giant machines for making alcohol. They have water, and with some thickening agents, and bottles, that's all they need.",
"Ethanol (ethyl alcohol) is a primary component of many hand sanitizers because of its effectiveness. \n\nBasically any entity that can normally produce a 40% ethanol-in-water solution (aka vodka) can probably retool their production to achieve a 60-70-ish% ethanol concentration. From there just add a few other commercially sourced ingredients to thicken it a little and add a scent and figure out some way to seal it in plastic bottles. (Which may not be impossibly different from filling glass bottles)."
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1eqfah | Has there been an increase in the amount and severity of storms in the last 10 years? | Hurricane Sandy, big snow storms, tornadoes leveling out cities...are we seeing more of these because of global warming or because of other factors like population increase, news coverage, or the way we measure/record? | askscience | http://www.reddit.com/r/askscience/comments/1eqfah/has_there_been_an_increase_in_the_amount_and/ | {
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"I am not a meteorologist, but [this](_URL_0_) is a paper that specifically discusses tornadoes. It's from 2008, but is a non-paywalled paper that addresses the question \"Does Global Warming Influence Tornado Activity?\". (If anyone has access to more recent papers or information, definitely share.)\n\nCheck out the graphs on the second page of the paper - there has been an increase in the number of tornadoes reported, but a decline in the number of severe tornadoes. The authors point out that the increase in reported tornadoes may be due to better reporting/detection methods and a growing volunteer network of storm spotters. They also speculate that tornadoes may have been incorrectly classified as too severe earlier in the history of meteorology, whereas now we have better technology for measuring the severity of them.\n\nThe authors suggest that it is still unknown whether or not global warming would result in more frequent or more severe tornadoes, because it is a combination of different atmospheric conditions that result in tornadoes, some of which are augmented by global warming, and some of which are diminished.",
"The most comprehensive survey of the literature on this subject would be the [IPCC Special Report for Extreme Events](_URL_0_), so that may be worth a read if you're interested in the subject. Meanwhile, this is what I recall off my head:\n\n**Hurricanes or tropical cyclones.** The trends associated with tropical cyclones vary substantially from ocean basin to basin. Furthermore, reliable records only began with satellite, which means we have only a rather short record (in terms of studying climate change). No firm conclusions can be made at this point, but it appears that the *number* of tropical cyclones *globally* will remain the same, but the *intensity* will change: there will be more intense cyclones and less weak cyclones.\n\n**Snow storms.** Snow storms are obviously dependent on a multitude of factors including humidity, but one of the key factors is temperature and we know that on average the temperature will increase. The SREX reports with at least some confidence that cold waves are less likely due to climate change, so I would think that snow storms will also become less likely. So on this extreme, climate change is a good thing.\n\n**Tornadoes.** For this, I refer to the SREX (pg. 164): \"A number of recent studies have addressed observed changes in wind speed across different parts of the globe, but due to the various shortcomings associated with anemometer data and the inconsistency in anemometer and reanalysis trends in some regions, we have low confidence in wind trends and their causes at this stage.\" So on this, we don't know.\n\nTL;DR: We are relatively confident that some extremes are increased by climate change; but for many we have little confidence.\n\n\nEDIT: I should also add that even if the extreme is not affected by climate change, its impact may be. For example, even if a warming climate does not affect tropical cyclones, it will nevertheless cause a rise in sea levels, which will worsen the storm surge associated with tropical cyclone.",
"Remember though the Super outbreak of 1974 was during a period were we thought it was Global cooling that caused the extreme weather. ",
"Officially, it [has been stated](_URL_2_) that:\n\n > *\"There is insufficient evidence to determine whether trends exist in small scale phenomena such as tornadoes, hail, lighting, and dust storms.\"* - **2007 United Nations IPCC report**\n\n[Here's a graph](_URL_0_) from that page. The chart is obviously going up over time, but it's almost certainly from increased detection rate. The following possible reasons are given by the article:\n\n > 1. Population growth has resulted in more tornadoes being reported.\n* Advances in weather radar, particularly the deployment of about 100 Doppler radars across the U.S. in the mid-1990s, has resulted in a much higher tornado detection rate.\n* Tornado damage surveys have grown more sophisticated over the years. For example, we now commonly classify multiple tornadoes along a damage path that might have been attributed to just one twister in the past.\n\n\n[Here's another good article](_URL_3_). One quote from it:\n\n > It all leads to an inevitable question: Is tornadic activity increasing? \n\n > \"There's no evidence that it is,\" says Joshua Wurman, president of the Center for Severe Weather Research. \"If you look at the frequency of tornado reports in the U.S., they're going up every decade, but there's pretty good evidence that it's due to improved reporting efficiency.\" \n\n---\nEDIT: Reporters will always say what they want, usually with little fact checking. In 1975, Newsweek [blamed global cooling](_URL_1_) for a tornado outbreak."
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396hk0 | when did american healthcare become so terrible, ie when did jobs with benefits become the epitome of a career? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/396hk0/eli5_when_did_american_healthcare_become_so/ | {
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"Health care being tied to employment started in World War 2. The government realized that with a lot of young men joining the military, and the increase in military production, that there would be a serious labor shortage. To try to control things somewhat they prevented employers from increasing wages. Once employers couldn't compete for labor using pay, they started looking for other perks that they could offer, one of which was 'free' health care. It stuck around after the war as something that people sort of expected.",
"America as a whole has trouble with worker benefits compared to the rest of the world. Some people have pointed some of the other key reasons here, but one is money in politics. \n\nCorporations lobby heavily, both the health insurance companies and large companies that don't want to pay benefits. They're very good at quashing benefits with the \"You're forcing other people to pay\" or \"you're killing jobs\". \n\nHence no socialized healthcare, maternity leave, or regulations on banking etc etc. \n\nBasically, the people who don't want people to have socialized healthcare or benefits have money to support politicians. People who need socialized healthcare don't. \n\n",
"The decline of the healthcare system into the nightmare it is today began with the rise of the health insurance companies in the early 1960s. They are the very root cause of the toxic mess we have today.\n\nThere had been health insurance, and even talk of universal healthcare for many decades prior to that, but it was the 60s when the insurance companies began to go mainstream and toxic. \n\nAlthough the Republicans had long been violently opposed to the notion of universal healthcare (which they assigned the boogeyman name of \"socialized medicine,\" because they knew people would associate it with Scary Communism), President Nixon was actually originally in favor of universal healthcare, and *might* have been able to put the brakes on the growing problem, but a couple of good old boys from Kaiser came around and had a chat with him, and immediately afterwards, he dumped his support for universal healthcare in favor of private insurance. And that was the last realistic chance we had of getting decent universal healthcare.\n\nAs they moved more and more into the mainstream, they brought truckloads of money with them. When people had to pay their own medical bills on their own, doctors had to charge prices people could actually afford. But when that person has a big corporation paying the bills, well, why *not* raise the price of the $5 office visit to $100?\n\nAnd then there was an avalanche. Healthcare became a *major* for-profit industry, as opposed to the mon-n-pop business nature of most doctors previously. Private for-profit hospital corporations sprang up. Medical device makers started building ever-more-expensive (and TOTALLY necessary) medical devices. The pharmaceutical industry went blasting into the stratosphere. Even private-practice doctors moved into the big time, though they typically don't make anything NEAR what the big corporate medical companies do.\n\nNow it's too late for decent universal healthcare in the US. The only way we could get it is by burning the health insurance companies to the ground and starting over, but that's hundreds of billions of dollars and tens or hundreds of thousands of jobs, so it ain't gonna happen.\n\n"
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3pe0a9 | How true to history is this anecdotal account of Nazi-occupied Austria? | _URL_0_ | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/3pe0a9/how_true_to_history_is_this_anecdotal_account_of/ | {
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"Memories, facts, half-truths, presumptions and defamation mixed together."
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415r8c | Since the sun is largely composed of helium and hydrogen, could you theoretically fly through it? | askscience | https://www.reddit.com/r/askscience/comments/415r8c/since_the_sun_is_largely_composed_of_helium_and/ | {
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"No, for very much the same reasons (and more) that [you can't fly through gas giants](_URL_0_). You can only fly through hydrogen and helium at earth-like pressures, and pressures (and temperatures) in the sun get astronomically bigger than that (pun definitely intended). No substance, even theoretical, could survive a flight even a small percentage of the way into the sun.",
"Just to put this in perspective, the sun's core which is also helium and hydrogen is really dense. [It has a density of 150 g/cm^3 (150 times the density of liquid water) at the center](_URL_0_)\n\nFurther from the center, it will be much less, but not that much less. [Here's a logarithmic plot](_URL_1_) of the density of the sun with distance from the center and comparison to liquid water.\n\nThis is not even taking into account the fact that no material can be solid (or even liquid) at those temperatures.\n\nSo, you could magic an airplane and fly though some of the sun."
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1xtofh | what are the properties of software licenses? | There are many licenses that you can have for example GPL, MIT, Apache, BSD... Can anyone explain the difference like I'm 5 because when I enter their website I find many legal stuff with formal language which I can't understand as english is not my native language. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1xtofh/eli5what_are_the_properties_of_software_licenses/ | {
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"### Standard Disclaimer - I am not a lawyer. This is not legal advice. If you require legal advice, seek the services of a legal professional.\n\nGPL is a copyleft, open source software, Free Software license.\n\nMIT/X11 License (aka MIT) and the various BSD licenses (except the original four-clause version) are copyfree, \"permissive\", open source software, Free Software licenses.\n\nApache License 2.0 is an open source software, Free Software license, and some people consider it \"permissive\" as well, though others do not.\n\nI'll give more detail about the licenses specifically in a bit. First some general stuff.\n\n---\n\nIn short:\n\n\"Proprietary\" is the default state in most industrialized (or \"post-industrial\") nations. The moment you put something down on paper, save it to a hard drive, or otherwise fix it in a persistent form, copyright applies in such nations (e.g. the United States and EU). That basically means someone \"owns\" the copyright and is not waiving (m)any privileges granted by copyright.\n\n\"Public domain\" is the sum total of all works whose forms are subject to copyright but are not covered by copyright themselves. This includes things whose copyrights have expired and, in theory at least, things some people have intentionally dedicated to the public domain before the term of copyright ended. Some jurisdictions (e.g. France) do not recognize a right to dedicate a work to the public domain, though, so one might dedicate something to the public domain somewhere else, then still sue people for using it in a manner of which one disapproves in France.\n\n\"Open source software\" and \"Free Software\" are roughly the same thing, in technical/legal terms: software that you are allowed to use, modify, and share with others, possibly subject to certain restrictions. This status is achieved by using an open source software or Free Software license. The Open Source Initiative maintains the [Open Source Definition](_URL_2_) and the GNU Project (in association with the Free Software Foundation) maintains the [Free Software Definition](_URL_1_).\n\n\"Free culture\" (and some similar terms, e.g. \"open content\") is much the same thing as open source, but for non-software works.\n\n\"Share-alike\", aka \"viral\", is a characteristic of licenses that affect work created by other people, \"infecting\" that work with the same license. Generally how it works is that you have some work someone else distributed under a share-alike license, and you decided to use part of that work as part of another work you are creating, and the share-alike license requires you to use the same license for the whole thing (not just the original part and whatever minor modifications were made to it directly). This can cause problems, because share-alike licenses are by default legally incompatible with other share-alike licenses and, in nontrivial ways, with pretty much every license in the world that is not the same exact license.\n\n\"Copyleft\" is a combination of \"share-alike\" with a legal restriction that requires you to distribute the sources for any modifications you make whenever you distribute it in non-source form.\n\n\"Permissive\" is a very hand-wavy term that means basically whatever the speaker intends it to mean. In general, however, when people say \"permissive\", they mean it isn't proprietary or share-alike or copyleft. Sometimes, weakly copyleft works (e.g. the LPGL, which in some cases can be used for software libraries so that they do not \"infect\" the licensing status of software that uses those libraries, or the CDDL or MPL which are considered \"per-file copyleft\" whereby it doesn't affect things in separate files) are referred to as \"permissive\", however, and there is some debate even among those who reject calling any copyleft license \"permissive\" about whether something like the Apache License 2.0 is \"permissive\".\n\n\"Copyfree\" applies to any license that, in essence, very closely mimics the permissive conditions of the public domain, but without the jurisdictional problems and other uncertainties of the public domain; it also applies to a work released under such a license. The Copyfree Initiative maintains the [Copyfree Standard Definition](_URL_0_).\n\nI hope this helps. I'm leaving out a lot of detail, because I'm trying to keep this relatively short and simple.\n"
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4tjcvl | how is it possible that we have developed a drug that is 95%+ effective in preventing the transmission of HIV, but the best we can do with cancer is reactive treatment that is invasive and uncomfortable at best, with no real guarantee of success? | what am i missing here? i know that PrEP hasn't been around for long, so efficacy can be taken with a grain of salt. but it really blows my mind that if you get cancer your options are really (1) invasive surgery to remove the cancerous tissue, often extending to surrounding and often times healthy tissue and/or (2) chemotherapy, which is no walk in the park, and/or (3) radiation, which speaks for itself. i know there are new/experimental cancer treatments and therapies (CAR-T, for example) that are promising, but how are we lagging so far behind on the cancer front? and how do we not have any preventative treatment options, other than "living a healthier lifestyle" or genetic testing that ultimately leads to options 1, 2, or 3 above anyway? | askscience | https://www.reddit.com/r/askscience/comments/4tjcvl/how_is_it_possible_that_we_have_developed_a_drug/ | {
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"HIV/AIDS is a single condition. Cancer is simply a catch-all term for an entire group of conditions with commonalities but each has unique symptoms, causes and treatments. Chemotherapy and the like mainly attacks the things they have in common ie the uncontrolled cell division.\n\n\n\n Basically, what I'm saying rather poorly is the lack of a effective cure is at least partially due to the variabilities of cancer and the spread out research and funding for such.",
"Many cancers are now pretty much completely curable, especially children's cancers; many of them have gone from 90% mortality 40 years ago, to virtually 100% curable today. For some reason, this amazing progress seems to have been almost invisible to the general media, but it shows that your premise is wrong. \n\n[Pediatric Cancers in the New Millennium: Dramatic Progress, New Challenges](_URL_0_)\n\n[Survival trends over time in children's cancer](_URL_1_)\n\n"
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5ru07g | what are those white stone looking things that come out of you mouth that smell horrible? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5ru07g/eli5what_are_those_white_stone_looking_things/ | {
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"Tonsil stones?\n\nNot everyone gets them. They are also called tonsilloliths.\n\nThey are basically made out of bone material.",
"Tonsilloliths, sometimes called tonsillar concretions. A buildup of calcium, mucus, and bacteria.",
"Eating carrots supposedly helps. I have these almost every day. I bought one of those water picks that you can adjust the pressure on and wash out the cavities in my tonsils, seems to work. ",
"these white stone secretions i usually cough up from the back of my throat smell like crap when squeezed. ive had this problem since childhood (im 36 now). and ive noticed that the more sugar i eat, the greater the chance i cough a stone up later on at night or early morning. basically, if i eat no sweets nor too much sugary items, then no stones develop."
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4wwh5r | how come manufacturers can get pixels so small for a phone screen and can't do the same on big led screens? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4wwh5r/eli5_how_come_manufacturers_can_get_pixels_so/ | {
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"They absolutely can do this.\n\nHowever, they don't usually bother - because it's very rare that you'd look at a big screen from the same kind of distance (just a few inches) as you'd look at a phone.\n\nCreating this many pixels so close together is expensive, and at the distances from which you'd normally look at larger screens, it's very rarely worth the expense of packing them in this tight.\n\nThis is why, in designing their \"Retina displays\", Apple [take account of typical viewing distances](_URL_0_):\n\n > When introducing the iPhone 4, Steve Jobs said the number of pixels needed for a Retina Display is about 300 PPI for a device held 10 to 12 inches from the eye. One way of expressing this as a unit is pixels-per-degree (PPD) which takes into account both the screen resolution and the distance from which the device is viewed. Based on Jobs' predicted number of 300, the threshold for a Retina Display starts at the PPD value of 57 PPD. 57 PPD means that a tall skinny triangle with a height equal to the viewing distance and a top angle of one degree will have a base on the device's screen that covers 57 pixels. Any display's viewing quality (from phone displays to huge projectors) can be described with this size-independent universal parameter\n\nAt bigger distances, it takes few pixels per inch to get the same number of pixels per degree.",
"They can and they do. It's why we now have 4k TVs.\n\nHowever, while people are more than happy to pay upwards of $1000 for a phone with a 5 inch, it's been well established that they aren't willing to pay proportionately similar prices for a TV (10,000 for a 50+ inch tv?). Now to be fair there is more going on in the price of a phone than just the screen, but screens are one of if not the biggest expenses and scaling the screen up to TV size would make it extremely expensive, well beyond the sub-$2000 price point that almost all TVs are sold at.\n\nBut TV technology is driven directly by the massive amount of pixels phone screens are able to pack into tiny screens. As the technology to make these phone screens advances and becomes cheaper it moves into the TV space where it can be done for an affordable price for consumers.",
"Part of the problem is that each pixel you make has a small chance of being faulty. When you pack a much larger number of pixels into a larger screen, there's a greater chance that some of the pixels will be faulty and you can't sell the screen. Either you invest in better manufacturing processes which make fewer faulty pixels, or you charge more for the good screens to cover the cost of the faulty screens. Either way, a screen with twice as many pixels ends up costing more than twice as much.",
"The actual reason is that there are industry resolution standards that need to be adopted by manufacturers, broadcasters, etc. The industry decides on certain resolution standards (eg. 480p, 720p, 1080p, 4k, 8k, etc.). We've slowly been getting improvements in our resolution standards but the jump to having 500+ pixels per inch in a 70\" tv would be an absolutely huge resolution the industry isn't ready for. Prices for tech have to come down, streaming infrastructure needs to be supported. Eventually, we will have the equivalent pixels per inch of a high end phone in our tv but even then the pixels per inch will vary depending on the size of the device because it will still be rated based on the resolution standard. so if we have a 8000p tvs that means there are 8000 rows of pixels regardless how tall the tv is. There will always be more pixels per inch in a smaller device than a larger device with the same resolution. \n\nEdit: To put in perspective - to get the same 500 pixels per inch that a high end phone has - a 70\" tv would have the resolution of 17,159P. The current highest end concept tv resolutions are 8K (7680×4320) or 4320p. ",
"They don't put tiny pixels on a large TV because you sit far away from your TV (unlike your phone) and you don't need the pixels to be small.\n\nHere's some math:\n\nIf you have a 5\" HD phone screen (resolution = 1920 × 1080 which is 2K video), then you have around 440 pixels per inch (PPI).\n\nIf you created a 60\" TV with that same PPI value it would have a resolution of about 23007 × 12940. That's 297K video. Since nobody makes videos, movies, or TV of that insanely high resolution it's just wasted pixels.",
"Well they absolutely can, there is just no point in doing so. \n\nUntil very recently, graphics cards only had enough bandwidth on their displayport connectors to do 4K at 60hz (60 FPS). Now, with the newest version of displayport, cards can theoretically push 8k at 60 hz. However, these displays don't exist yet and won't for quite a while, as their is no purpose of having them. \n\n4K content is already limited enough, and cable TV providers most likely wont have it for a few more years. 8K content won't be common until at least a decade from now, if that."
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60hrgc | why do so many shows for children in elementary school feature characters in middle and high school? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/60hrgc/eli5_why_do_so_many_shows_for_children_in/ | {
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"Just like when kids play with dolls that are grown up, they are drawn to characters older than themselves. They can imagine themselves older and more mature. \n\nThe same goes for books. The first Harry Potter book is him at 11 years old, but it is mostly first read by 8-10 year olds.",
"Shows about children their own age would be the same stuff they do every day, that's not very new.\n\nShows about children younger than them would be a rehash of their experiences, that's why they go from \"love Barney\" to \"Barney's for babies\".\n\nMost folks are looking forward, imagining their future, so shows that could be their future are more interesting. "
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slk2p | Does the dilation of our iris work like the f-stops on a camera, increasing depth of field as the hole gets smaller? | So on camera there is a thing called f-stop. It controls the amount of light being let into the camera, and does this by making a hole that gets bigger and smaller. [Here is a picture.](_URL_0_). At f-16 it lets in less light, like an iris contracting to let less light into the eye. At this f-stop the camera has a very deep depth of field, or how far away subjects can be from each other and still have them all in focus (to explain it very roughly). A deep depth of field means they can be very far away from each other in relation to the photographer. At f-5.6 the hole is much larger, and lets in much more light. However, it makes it have a very shallow depth of field, meaning the subjects must be a close distance to each other in relation to the photographer.
So does my iris work like this? Does my eye have a shallower depth of field the more dilated my eye is? | askscience | http://www.reddit.com/r/askscience/comments/slk2p/does_the_dilation_of_our_iris_work_like_the/ | {
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"WhatDoes is correct, albeit a short answer. But I don't think that warrants downvotes just because he didn't go into intense detail. The answer is yes, your pupils constrict both in high light situations and from parasympathetic (rest and digest) activation to allow for better \"distance\" vision. This is called accommodation. \n\nThe opposite happens during sympathetic innervation (fight or flight) where the pupils dilate to accommodate nearer objects. Think of it as if you are running away from something, you want to focus on what is closer to you so that you don't trip and fall. Or if you are fighting, there is no benefit to to seeing what is far away if you are focusing on finding your opponent's weak point. Versus parasympathetic you may want to focus on what's far away so that you can plan your next meal. ",
"Kind of, as DOF is a function of aperture, but what you actually see is far more complicated.\n\nFor example, from \"The depth-of-field of the human eye from objective and subjective measurements\"\n\n > There is a clear decrease in the DOF between 2 and 4 mm in all cases, but our objective data show that for larger pupils DOF increases in some cases.\n\nThe reason why is not perfectly clear, and I don't feel completely sure of myself to explain the different hypothesis.\n\n_URL_0_"
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1u0gzr | What made melee cavalry so effective in ancient times? Was there much variation in their usage before the advent of gunpowder? | Were cavalry more effective as a morale breaker than an actual killing force?
Or if they were effective at directly inflicting casualties then how much of this was due to the riders skill vs. the horse simply trampling soldiers in it's path?
And finally was there much variation in cavalry tactics before the advent of gunpowder?
Bonus question: How were war horses trained to charge through groups of soldiers? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1u0gzr/what_made_melee_cavalry_so_effective_in_ancient/ | {
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"This is simply an incredibly broad question. Different armies at different technological levels with different cultural backgrounds made practically every use of cavalry. Some were merely scouts and harassing units; others were directly involved in heavy fighting. If you'd like to see the classic example of ancient cavalry used to win battles, check out a history of Alexander, who (very simplistically) was famous for using the infantry as an anvil to hold the Persian army where he wanted it so that he could use his cavalry to deliver the knockout blow. The mobility of cavalry meant that commanders like Alexander could deliver a local superiority of force at critical points in the battle despite having fewer troops on the field.\n\nMuch of Hannibal's success came from his excellent Numidian cavalry, and after the Numidians switched sides, he lost against a roughly equal Roman army at Zama.\n\nIn all, cavalry almost always offered mobility. They could also be effective shock troops due to the weight of the horse and the additional height horses offer. Some ancient cavalry was armored more or less as heavily as medieval knights. Cavalry generally tried to outmaneuver and attack from the flank of the enemy where possible, which they could do because of their speed, but we do see Alexander using direct charges to break and disintegrate enemy infantry formations, as at Chaeronea, where he led cavalry under the overall command of his father Philip II.",
"I would highly recommend this thread from a few days ago, (_URL_0_). /u/BeondTheGrave, /u/elos_ and /u/Agrippa911 all provide pretty good answer concerning cavalry through the ages, the latter two being more in line with the time period you are looking towards."
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1z1dxz | If electrons are perfectly spherical, how do we know they have spin? | I'm learning Quantum Chemistry and this is really bothering me.
EDIT: to be more specific, the spinning of the electron is assumed to be the origin of intrinsic angular momentum we observe in all quantum particles. i guess (?) we assume the electron is spinning because in other models of spinning spheres (i.e. the earth) it is generated this way.
this was very disturbing to hear. i can't stop thinking about it.
TL:DR "Spin" is just what they called it at the time of the discovery. The electron couldn't possibly be generating angular momentum due to it's spin because it would have to be spinning faster than the speed of light. Therefore, it has been deemed an 'intrinsic property'. It has angular momentum but we don't know why except that mathematically we can demonstrate that the value 1/2 as the quantum spin number works in our equations.
_URL_0_ | askscience | http://www.reddit.com/r/askscience/comments/1z1dxz/if_electrons_are_perfectly_spherical_how_do_we/ | {
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"One of the most challenging things about quantum theory is that you have to abandon notions of elementary particles being like common macroscopic particles. An electron is not a ball that is orbiting a nucleus like the earth orbits the sun, at the subatomic scales, electrons exhibit particle and wave properties, kind of like light, and therefore comparisons to balls or spheres don't really hold. So saying that an electron is spherical, is kind of meaningless since the electron itself does not really have what we would define as volume, or shape. The graphical depiction of the probabilities of it's position can be spherical depending on it's energy state, but that is different than what you think of as volume.\n\nNow as for spin, that is just a problem of the naming system. An electron spin does not mean that the electron is spinning around its axis (again, it has no volume or shape), it is just the name we give to the property of electrons. Electrons have a measurable magnetic moment, and at the time of that discovery, physicists knew that electrons hold charge. They also knew that if a charged object spins (has angular momentum), then it will have a magnetic moment. So they gave the electron a property of \"spin\" which would correspond to the different magnetic moment it could have, either up or down (since angular momentum, like all other properties of matter is quantized). And that's where spin comes from.\n\nSo when you think about spin, just think of it as a name for a property of a given electron. It can be either up or down."
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3ybbez | what happens when someone od's on specific painkillers? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3ybbez/eli5what_happens_when_someone_ods_on_specific/ | {
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"An overdose on opiates causes respiratory depression to the point where you stop breathing and die. Benzodiazepines also have cause some respiratory depression as well. Both also cause a flood neurotransmitters that are responsible for feeling pleasure. Essentially, an overdose on both would cause you to fall asleep and stop breathing, it's very peaceful. Source: I am a paramedic who regularly uses these drugs and I've also done overdoses as a result of them."
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1hjquv | how do messages in a bottle work? | I know it seems like a simple question, but is there some form of art behind it, do you have to throw the bottle at a certain time, in a certain direction? or do you just throw it and hope for the best, ALSO, how do people get their replies to the right person with such accuracy? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1hjquv/eli5_how_do_messages_in_a_bottle_work/ | {
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"Pretty much just throw it out there and hope. I'm sorry to have to tell you this, but the portrayals of the practice in BC are largely inaccurate.",
"You just put the message in a bottle and sail it, hoping the ocean / lake / whatever currents take it somewhere where people will find it. It is almost impossible to return a message in a bottle with accuracy, unless one has some kind of supernatural understanding of ocean currents and weather patterns.\n\nYour best bet would be to enclose an e-mail or something with the message. It would go something like, \"Hey! I'm joshjs94, and i wrote this message. email me at joshjs94@whatever.com if you find it!\". You could ask them to tell you the location of where they found the bottle, and what date, so you can get a bit of an understanding where your bottle went.\n\nYou cant really aim a message in a bottle, unless you are crazy prepared, and as was said before, have vehement (intense) knowledge of weather patterns and currents, among other things."
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3wdr63 | why does the stock market respond to falling oil prices with sell-offs? shouldn't every sector that uses energy to make and ship their products see increased profits? | I have a lot of money in the stock market right now, and I'm getting frustrated with the constant nosedives the DOW and S & P keep taking being blamed on low oil prices. I get that low oil prices hurts Exxon Mobil and BP, but energy is only 5.9% of the US economy:
_URL_0_
The other 94.1% of the economy *purchases* energy in order to manufacture and ship goods. Cheap oil should do wonders for the profit margins of the vast majority of the economy. What's more, cheap gas means more consumer spending in every other sector. When 20 stocks are trending upward for every one that crashes, my stock ticker should be bright green. Why is it red? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3wdr63/eli5_why_does_the_stock_market_respond_to_falling/ | {
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"Generally speaking, a falling price of oil means falling demand for oil, since world oil production is reasonably stable. Falling demand means that companies expect to be purchasing less oil in the future (since a lot of oil is purchased on a futures basis), which indicates that they expect to be doing less of all those things you mentioned that burn oil. So, on average, when oil drops it indicates that the economy expects to be less productive in the near future.",
"If you need financial issues explained to you on ELI5, you just *shouldn't* be following the financial news. Your stocks will rise in value over time if you invest them in a diversified, passively managed index fund. Your job as a responsible investor is to only put in money you don't need right now, and not check the balance of your brokerage account for another decade. \n\nFlooey's answer isn't *wrong* - in general, higher oil prices can be seen either as a sign of rising costs of production *or* as a sign of strong global demand. Which side of the equation is more important for assessing future economic growth is a complicated analytical question. But more importantly, *the financial sector has tried to predict both of these effects long before you even thought about them*, and changes in the market reflect a difference between recent information and pre-existing predictions, not between recent information and older information. A price of oil that is lower than last year's price could be either higher or lower than *what analysts were predicting for this year's price*, and that difference is what is likely to move markets. But it gets even more complex than that - the market is anticipating rate hikes from the Fed, which will cut economic production. Good news for the economy tends to push the Fed towards rate hikes, which are (in the short term) bad news for the economy. So current faster-than-expected economic growth can be good evidence that economic growth will slow within a few months. And there are even stranger interconnections between stock prices. Famously, when Russia defaulted on its ruble-denominated debt, the difference between the price of Royal Dutch and Shell (which are the same company, but listed separately as a British and a Dutch stock) spiked. Why? Because a huge hedge fund that was betting Russia would never default on ruble-denominated debt without also defaulting on dollar-denominated debt was *also* betting that Royal Dutch Shell would never pay a dividend to the Dutch stock without paying a profit to the British stock, and when they lost money on the default they had to unwind their position in Royal Dutch Shell, too, selling Shell and buying Royal Dutch. \n\nIf it's not your job you shouldn't waste time thinking about it. Stay diversified, don't pick stocks, invest for the long term, keep money you need in the near future out of risky assets.",
"It's market reaction, to give you the absolute simplest explanation. The movement is not so much based on what happens, but what people *thought* would happen, and their reaction to the reality. Oil plummets, people panic, all hell breaks loose.",
"Lower prices suggest less is being used.\n\nIf less oil is being used, that suggests an economic slowdown.\n\nI think.",
" > I have a lot of money in the stock market right now, and I'm getting frustrated with the constant nosedives the DOW and S & P keep taking being blamed on low oil prices.\n\nSo then stop listening to CNBC and the other feces-throwing chimpanzees who make such absurd claims.\n\nSometimes crude and stocks move in the same direction, and sometimes they don't. Oil plunged by 50% in the middle of 2014, and stocks were mostly flat, being somewhat up.\n\nNo matter which way things move, some hysterical asswipe is going to be on TV or the internet spinning stories about it.\n\nIf this bothers you so much, you need to get rid of some of your stock, and all of your TVs.\n\n",
" > The other 94.1% of the economy purchases energy in order to manufacture and ship goods. Cheap oil should do wonders for the profit margins of the vast majority of the economy. What's more, cheap gas means more consumer spending in every other sector. When 20 stocks are trending upward for every one that crashes, my stock ticker should be bright green. Why is it red?\n\nA few things wrong with your reasoning. First 94.1% may use oil, but to varying degrees, and it may not be that large a part of their business, which would then not really affect the bottom line of the business all that much. Additionally, the 5.9% that represents energy is directly and fully affected by oil, so when oil prices go down, the affect of oil prices on the 5.9% is relatively large compared to the affect on the 94.1%. Second, cheap gas does not mean more consumer spending in EVERY other sector, in fact its been shown that people have largely just spent that money on restaurants.\n\n I agree with simpleclear that it largely has to do with the fact that no one predicted oil to be this low for this long, and this causes a lot of uncertainty in the financial markets because many countries' economies are based on oil production. Market uncertainty increases the risk of all investments, which in turn brings prices down as investors would demand more upside for the additional risk."
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ex46jh | why does the us senate vote on whether witnesses may appear? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ex46jh/eli5_why_does_the_us_senate_vote_on_whether/ | {
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"There are no actual hard set rules. During Clinton's trial the senate called three witnesses, during Jackson's trial they called around 40. This time around the whole thing is just a political circus that even if they did call any there would be none that actually paid attention to what they said anyways.",
"We say that the Senators are to act as jurors, but it’s more accurate to say that each acts as a judge. As for why they are allowed to vote on having witnesses: the protocol states that only the Senate may try an impeachment, saying they MUST hear testimony is as incorrect as saying the House MUST vote to start impeachment proceedings.\n\nAlso, this question is begging for misinformation. Every impeachment trial in the history of the USA has had witness testimony in the Senate. It’s just common sense that a person passing judgement would want to have as many facts as possible.",
"Impeachment is probably the most direct interaction of the three branches of government. It's very important that the Chief Justice stays in the judicial branch lane no matter what his personal opinion may be. Had the vote for witnesses been 50/50, I strongly believe he would have abstained and let the motion die."
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2gz922 | how can companies that sell "aged" goods (e.g. wine, cheese) predict the demand for their goods so far in the future? | Any demand for goods can fluctuate constantly, so how do companies with long-term manufacturing/aging process reasonably match their supply with a demand years in advance? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gz922/eli5how_can_companies_that_sell_aged_goods_eg/ | {
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"Wine and cheese are pretty common and basic items so the demand for them is pretty stable through time. They look at their previous sales and current demand, look at population growth, and then predict how much wine will be in demand in say 10 years. Unless something major happens there is no reason for wine and cheese demand to suddenly plummet.\n\n",
"Past experience can give you a surprisingly good idea. I did read about a whiskey distiller that ran into supply issues recently due their 12 year becoming quite popular. I'm actually curious if that same distiller will also have issues with their 18 year in a couple years, since I imagine if the demand for one is low they just don't bottle some of it and let it age longer.",
"Most aged goods sell for a premium. Most of the companies will artificially keep the supply of the aged goods low so that the price for each item is higher.\n\nThis means that they usually have much more goods than they would actually sell. In some industries like wine, much of the excess grapes will be sold cheap to other companies that will combine wine grapes from many vineyards (think Trader Joe's Charles Shaw wine). Since it doesn't carry the label of the \"aged wine\" and it usually isn't in the same price category, it doesn't affect the premium price of the aged name brand product. In other food industries, the excess is sold and relabeled as store brands.\n\nOther times, they can just let an excess supply of products age longer and then release them when they're older (and more expensive) for special \"reserve\" editions.",
"It's very difficult and a lot of times they don't. A few years ago if you remember there was a tequila shortage. It takes roughtly 15 years to grow the agave to the point that they can use it to make the tequila, 15 years ago they didn't expect the sudden rise in demand.\n",
"The real answer is big business.\n\nGo to the liquor store today and you'll see all kinds of 10+ year aged boutique whiskey from small shops. Those shops are indeed new and small but their liquor is not. [It's purchased from MGP](_URL_0_), a large company in Indiana that has a bunch of aged whiskey to sell to other whiskey makers (or \"makers\" as the case may be) to help them start or augment their brand.\n\nMGP \"is now a one-stop shop for marketers who want to bottle their own brands of spirits without having to distill the product themselves. MGP sells them bulk vodka and gin, as well as a large selection of whiskies, including bourbons of varying recipes, wheat whiskey, corn whiskey, and rye. (They also make “food grade industrial alcohol” used in everything from solvents and antiseptics to fungicides.) Their products are well-made, but hardly what one thinks of as artisanal. And yet, much of the whiskey now being sold as the hand-crafted product of micro-distilleries actually comes from this one Indiana factory.\""
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xk65e | When, why, and how did the U.S. prison system become privatized? | Also if you can recommend further reading (articles, papers, books, whatever) it would be very much appreciated! | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/xk65e/when_why_and_how_did_the_us_prison_system_become/ | {
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"Your question is a bit ambiguous and rests on a couple of false assumptions.\n\nFirst, there's no single US prison system. There's a mishmash of systems--the federal civilian system for those imprisoned for crimes committed under federal jurisdiction, the military system, and individual state systems for crimes committed under state jurisdiction. There are also local systems for petty offenses (typically those for which the term of imprisonment is less than one year or for those awaiting trial on state charges, operated at the municipal level).\n\nFurthermore, full-on \"privatization,\" though in my opinion grossly regrettable, is fairly localized. Some state or municipal systems are; I believe that most still are not. At most, most systems might hire private contractors to handle certain services--e.g. food service, operating prison industries, laundry, etc.",
"In Ireland & the UK in historical terms prison as a justice system is fairly new. You had debtors prisons and bedlam in Ireland and you also had [slavery](_URL_0_), transportation and the death penalty for many crimes. You also had corporal punishment. \n\nLocally administered justice administered by a feudal lord was in effect privatised and that is what you inherit your US system from. \n\nIn Europe , where prison sentences are shorter and there is no death penalty , we often wonder how the US system evolved too. \n\nPrison for punishment and rehabilation really dates from Victorian times for us.\n\nSo what are you comparing it too ?",
"The [Wikipedia article](_URL_0_) on this subject is actually fairly thorough and well-sourced.\n\nAlso, according to [this](_URL_1_) article, a little under 10% of U.S. prisoners are currently in privately-run detention facilities.",
"There are several dozen state prisons that are private. Corrections Corporation of America OWNS 60 prisons.\n\nThe earliest privatization schemes that I know of emerged after the Civil War. This is referred to as \"convict leasing.\" The local or state authorities would sentence someone to prison, and then private individuals would rent the convict from the state. For the most part, this system mainly targeted African American males (it grew out of the false idea that African Americans needed to be controlled, and since slavery wasn't present, something else had to be done). \n\nThe really bad part of this was that the renters did not have a financial interest in their convicts. Under slavery, if someone worked their slave to death, they had to purchase another. Under this system, if someone worked a convict to death, the state simply replaced that convict. A pretty widespread saying at the time was: \"If one dies, get another.\" ---the lifespan of most incarcerated prisoners was about 5 years. \n\nThis made everyone a tremendous amount of money. The state made money from leasing convicts out (so the authorities began arresting and sentencing folks for less and less significant crimes). The renters made significant profits because they were paying super cheap for labor (they also didn't feed the convicts very well at all, and simply locked them in cages at night). Several states actually closed all of their prisons and just rented out every convict they had.\n\nThankfully, this died down around the 1920s or 30s when the public started to become aware of what was really happening (a couple white guys wrote about their experiences as convicts). \n\nCouple of really good books on this are: \nPenology for Profit by Don Walker\nWorse than Slavery: Parchman Farm and the Ordeal of Jim Crow Justice by David Oshinsky\n\nNow, Corrections Corporation of America does NOT operate like this at all. Prisoners now have more access to the legal system so the state can't just murder them all. CCA operates just like a regular modern prison. I'm not sure, but I would imagine that they'd be inspected on a fairly regular basis to keep the state from being sued for mistreating inmates. They popped up in 1983 when the US government was embracing privatization and deregulation of several industries. So if you put them into the economic context of the time, they make sense. This was when Reagan and other Republicans were preaching that the private sector was much more efficient in doing things than the government (some things they are, some things not so much). \n\nHope this helps,\nJohn",
"According to the US Department of Justice, about 10 percent of prisons are private.",
"This article gives a bunch of good information. \n\n_URL_0_",
"Not a historian, this is just something I know a smidge about. In places that they are privatized, the states or municipalities usually sold them off to private companies (typically with agreements to keep them at a certain percent of capacity) in order to balance a short term budget deficit.",
"I did my senior paper on the prison reform movement of the last half of the twentieth century in the USA but I only touched little on the privatization aspect but here is what I have. \n\nThe model set for the current prison system was set by the National Prison Congress in Cincinnati Ohio in 1870. The NPC set prison as an industry that should be operated efficiently and for profit. The idea that the prison operates \"for profit\" is what makes it a privatized prison. Privatized prison became an increasingly popular in the 1980s for housing inmates as overcrowding was happening.[1] Secondly, marketing prisoners was suppose to create a competitive market driving the cost down. However, 74 percent of all private prisons in the United States are controlled by two companies, Wackenhut (part of GEO Group Inc.) and Corrections Corporation of America.[2] \n\nBonus: The Freedom of Information Act can be circumvented by the for-profit firms' claims that releasing data could compromise their competitive advantage.[3]\n\nHope that helps some.\n\nSources:\n\n[1]Byron E. Price, Merchandizing Prisoners: Who Really Pays for Prison Privatization? (Westport, CT: Praeger, 2006), 2-8.\n\n[2]Price, Merchandizing Prisoners, 148-77.\n\n[3]Price, Merchandizing Prisoners, 47-53."
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agvg4n | When did humans start keeping track of their age? | What was the significance of it? Did they celebrate their birthdays somehow? How did they do so before the Gregorian calendar became standard?
Edit: What are the theories of how Biblical ages were determined? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/agvg4n/when_did_humans_start_keeping_track_of_their_age/ | {
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"This is more of a question for r/AskAnthropology. People have known how to count for far longer than we have a historical record for, so other means are needed to find the answer to this question. I have some thoughts on how to get an approximate answer, but they're not appropriate for this sub."
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1mhgm9 | why, when we see aesthetically pleasing things such as pretty sun sets, do we think they are beautiful? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1mhgm9/eli5_why_when_we_see_aesthetically_pleasing/ | {
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"I think there is something beautiful about something so unique. Aside from that, seeing variations in color that set a sky apart from a typical scene definitely doesn't hurt."
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4j8mxk | why do politicians always seem to have two mics at debates/rallies? | Shouldn't one be sufficient? It's not like there are multiple stations airing most of the debates. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4j8mxk/eli5_why_do_politicians_always_seem_to_have_two/ | {
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"It's largely to cope with failures. If Obama is in the middle of a significant briefing, the last thing you want is some technician running up to the podium shouting \"Hold on... can we do that last bit again? The microphone wasn't working.\"\n\nYou can also find that small differences in microphone positioning can really affect how sound is picked up. If the speaker moves, turns their head or whatever, you might find that your single microphone just isn't picking it up that well any longer, but two microphones in slightly different locations might do a better job.",
" > Shouldn't one be sufficient? It's not like there are multiple stations airing most of the debates.\n\nThe second mic is just a backup in case something happens to the first mic.\n\nDuring any major speech there are *always* many stations either broadcasting or recording the event to be broadcast later. The sound engineer sends a separate feed out to something called a \"press box\" which is essentially a professional grade audio splitter. It usually has a dozen or more connections that members of the press can use for their audio recorders or to hook up a feed to their satellite trucks. "
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[],
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873z42 | why are restaurants owned by the same company always right next to each other? i get offering variety, but isn't it a really bad idea to go into competition with yourself? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/873z42/eli5_why_are_restaurants_owned_by_the_same/ | {
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"One would assume the restaurants are marketed differently and are vying for different segments of the population. ",
"You're not going into competition with yourself though are you, just think of it as the same restaurant with a different menu cause that's basically what it is",
"It's the illusion of choice, they have very different menus and themes but they are both owned by the same company.\n\nThe location was picked by market research which shows there is a high volume of traffic in that area (like in a mall parking lot) so it's the optimal place for restaurants.\n\nAs for competing with yourself, is it really competition when the profits end up in the same pockets?\n\nSure there is extra cost in running basically 2 franchises but the key is that the chains are both profitable, and removing one wouldn't cause the first to get that much more business. More likely is that if there is the room for 2 restaurants than having two in that area is better than letting the competition put one of their restaurants next door and losing customers to them.",
"A building is selling something in a certain location because the location is the best for this business. As competitors develop and try to steal shares of the market, it is in their interest to compete in the most appropriate location, the one you found already. If they find a better location and put you out of business, then you can open a new shop next to them and try to compete them out of business.\n\nIf you sell ice creams outside an office and get your customers from that office on their way out of work, your competition wouldn't make money by opening up across the street as you would be the first ice cream salesman they see. Your competitor would have to open right next to you and offer a better deal to steal the customers from you.\n\nSource: _URL_0_\n\nTl;dr: 3 words are key in business - location, location, location\n\nEdit: added the source ",
"So, there are 3 restaurants on a block. It's a great location. All 3 are packed all the time. Wouldn't you rather own all 3, than just 1?"
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[],
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"https://youtu.be/jILgxeNBK_8"
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dnz7kh | why do i sometimes see microphones set up facing the crowd during a (music) concert? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dnz7kh/eli5_why_do_i_sometimes_see_microphones_set_up/ | {
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"Musicians wear in ear monitors. Headphones. The mics pick up the ambient crowd noise and make their mix sound less like a can.",
"Those microphones are set up to record the crowd.\n\nIn retrospect that seems a bit obvious, but it is a live concert recording so they want all the parts including the reaction of the audience. The microphones they have set up for the singers and the instruments are pretty good at just getting those parts, so the other mics pointed at the audience are to capture those sounds as well.",
"For a few reasons. \n\nOne reason is that the concert may be being recorded. In that case the band will want to record the sound of the audience to mix into the recording. \n\nThe other reason is that many performers use in-ear monitors to hear themselves and the other performers. While this had many benefits, one downside is that they can't hear the crowd as well. So the audio team will setup mics to capture the crowd and feed some of that into the performers in-ear monitors."
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2kbszm | if gay marriage is made legal (which is a good thing) what arguments would one use to keep polygamy illegal? | What I mean by this is that polygamy was banned for many of the same reasons gay marriage was. It goes against mainstream Christian values, it's viewed as taboo, it's unnatural, etc. If gay marriage is legalized what precedent would we have to deny polygamy? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2kbszm/eli5_if_gay_marriage_is_made_legal_which_is_a/ | {
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"The only real argument I heard against polygamy is the financial burden it could put on companies that employ people in this type of relationship. If employee X has three spouses not working, a company who is obligated to provide health coverage for them would be facing a greater financial burden than with a standard couple. But even that is kind of a sketchy reason. How many poly couples will be working at any given place. \nAlthough, letting a close but very sick friend into a marriage so they can get your company's health plan would probably become a thing.",
"Not that I have any interest in a poly marriage but honestly I don't know that there is a logical argument against it. As long as it's consenting adults then who cares how many adults are consenting? ",
"In theory none. Polygami isn't nothing inherently bad or evil. Problem is basically every polygamous society was enforced by men, for the benefit of men. And woman was treated mostly as a belonging etc... \n\nThe point is nobody is really lobbing for polygami in the more \"civilized\" society. So there is really no danger of legalizing it. I suppose the point of why it is not legal is because if we were to legalize it. It would bring more trouble than benefits.",
"It makes an absolute mess of family law.\n\nRight now, a marriage is between two people & a child has, at most, two parents. What happens to the children in a 3-marriage if A divorces B & C because B is abusive? Obviously, we would want to minimize B's custody rights but that would unfairly penalize C. What about a 4-marriage where A & B separate from C & D and A & B are the biological parents of children?\n\nDivorces can also be tricky - what about a 3-marriage where A & C want nothing to do with each other but still want to stay with B?\n\nAllowing gay marriage doesn't require any major changes to the legal framework of marriage - we simply change the definition to allow any two people rather than a man & a woman. Allowing poly-marriage would require a *major* reworking of the laws to accommodate arbitrary family size & structure to satisfy the needs of an *incredibly tiny* minority of people."
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147s02 | How much power does a radio receive from the wireless radio signal? Is this enough to do anything with? | There are a couple of AskScience posts about wireless charging already ( [here's one](_URL_0_) ), but what I'm wondering is how much power does a radio receive from the wireless signal and is there anything we can do with it besides charging electronics like we already talk about.
The power can be enough to run very tiny earbuds so you can listen to the broadcast, so since it's powerful enough to do that what else could we do with it? I know that's not much but it is something and it's already out there and free, so could we do something cool with it? Is it even enough to power an LED? | askscience | http://www.reddit.com/r/askscience/comments/147s02/how_much_power_does_a_radio_receive_from_the/ | {
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"Since we are talking about useful power received wirelessly, RFID (Radio-Frequency ID) works on this principle. You essentially have a reader (a handheld device that transmits power) and tags (devices on the various products that need to be identified). \n\nWhen the reader is switched on, wireless power is sent to the tag. The tag \"harvests\" this wireless power and transmits back to the reader information about itself. \n\nSo yes, in this case, this wireless power is all that is needed to make RFID tech work.",
"Back in the cold war days, many small \"bug\" radio transmitters in Britain worked by rectifying BBC Radio 1, a powerful radio station that blankets that nation. Instead of trying to incorporate and hide a battery, spies would run a little wire out from the bug to pick up tiny amounts of power from the aether. The power would arrive as ~1MHz AC, and be rectified with a little diode to make DC (like from a battery). That would yield just enough power to run a very weak transmitter operating on a different frequency, so you could listen in from a receiver outside the building. Very handy for bugging embassies.",
"if you harvested the minute wireless radio signals energy into a capacitor, say over a minute or ten depending on the source strength, perhaps it could be discharged into an LED. \nhere's a link to a neat invention to harvest energy off wifi signals: _URL_0_ ",
"Also note that the further away you are from the source, the greater loss you get by square of the distance. So if you're 2 feet from the transmitter, 2ft^2 = 4 x the power loss. 3ft^2 = 9x the power loss. (see radio propagation)\n\nWhat's neat is you'll get about the same power harnessing from say FM radio vs wifi. But with wifi, you'll use a smaller antenna because of the shorter wave. As others have said, you could charge a capacitor or battery over time."
]
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"http://www.reddit.com/r/askscience/comments/mv1ae/what_is_it_that_is_keeping_us_from_having/"
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[],
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"http://www.ifans.com/forums/threads/charge-idevices-over-wifi.358784/"
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pmrqj | the greek protests. how did greece get in such a hole? what do the protesters want? does the government have any other choice? | It seems to me that the EU is demanding Greece pass these measures, so does the government have any choice. What do protesters want? I know almost nothing, but from what I've gathered from cursory looks into it, it seems that the Greeks have a system that's unsustainable in terms of early retirement ages and benefits. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/pmrqj/eli5_the_greek_protests_how_did_greece_get_in/ | {
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"Here's are some previous eli5 posts that might help out:\n\n* [1](_URL_1_)\n\n* [2](_URL_0_)\n",
"I'm not sure if this should be a new topic - but what if Greece doesn't do these austerity measures? I know they passed them, but what if they continue to spend too much and collect too little? What can the other Euro countries do?",
"Greece could default on the debt, which is basically what Iceland did. Iceland is recovering fairly well. Argentina defaulted on their debt 20 years ago, and while they aren't doing great they recovered faster than Greece is projected to. \n\nThe protesters are mad because the government screwed up, and instead of using the \"we can't pay our loans, sorry\" method (which would screw the bankers), they are using the \"cut jobs, pensions, and salaries\" method (which screws the common citizen that had nothing to do with getting into this mess).\n\nIt's like if you worked on a team project, with you, Bob, and Jim. You work really hard on the project for weeks. When you go to turn it in, you find that Bob and Jim didn't do anything. But Bob and Jim tell the teacher it's your fault, so you get an F on the project while Bob and Jim get a B. You would be pissed too."
]
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"http://www.reddit.com/r/explainlikeimfive/comments/lhlz9/eli5_what_the_protestors_in_greece_want/c2suvl3",
"http://www.reddit.com/r/explainlikeimfive/comments/lnukb/eli5_why_is_greece_in_such_a_horrible_depression/c2ub7y3"
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440634 | what are the lingo/acronyms to enable me to converse on reddit? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/440634/eli5_what_are_the_lingoacronyms_to_enable_me_to/ | {
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"AFAIK: As Far As I Know... \nAMA: Ask Me Anything \nAMAA: Ask Me Almost Anything \nDEA: Does Anybody/Anyone Else... \nFTFY: Fixed That For You (correcting you, possibly jokingly) \nIAMA: I Am A... \nIANAL: I am not a lawyer \nIIRC: If I Recall Correctly... \nIMHO: In my humble opinion \nIMO: In My Opinion \nIRL: In Real Life \nITT: In This Thread/Topic \nNSFW: Not Safe For Work (mature content) \nNSFL: Not Safe For Life (graphically disturbing content) \nOC: Original Content \nOP: Original Poster \nOrangered: Your Reddit Inbox (Envelope) \nSMH: Shaking My Head \nTIFU: Today I fucked up \nTIL: Today I Learned \nTL;DR: To long; didn't read (summary) \nWoosh: Previous comment went over your head (you missed the joke)",
"also r/outoftheloop explains the memes and concepts you don't understand and everyone else seems to"
]
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89m00i | Why was Spain during its imperial period not able to colonize any other territories or islands in Asia, the Indian or Pacific Oceans save for The Philippines, the Marianas and the Carolines? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/89m00i/why_was_spain_during_its_imperial_period_not_able/ | {
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"Because it would have violated treaties with Portugal. The Treaty of Tordesillas (1494) established a line of demarcation in the Atlantic. Spain was granted rights to lands westward, Portugal to the east (it travelled through Brazil this allowing colonization there). The line confirmed Portuguese feitorias in Africa and their desire to get to the Indian Ocean and beyond. It also confirmed papal bulls to both nations that supported their expansion as long as they spread the Gospel in lands the reached. In 1529 the Treaty of Zaragoza extended that line around the poles but not perfectly (Portugal received 191 deg. and Spain 169 deg.). Spain's eventual conquest of the Philippines violated the boundary, but did not target an area of Portuguese trade."
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5kpcg9 | how did earth and other planets get moons, and is it possible for earth to get more? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5kpcg9/eli5_how_did_earth_and_other_planets_get_moons/ | {
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"Sometimes they were just things that were in the neighborhood that got captured by a planet's gravity. Sometimes they formed alongside the planet. Just as the planet formed from a particularly dense bit of dust and gas gathering up more and more mass through gravity, a moon can form from a separate, smaller dense bit of matter that creates a separate gathering point for matter and you end up with multiple bodies all orbiting around each other. The way the Earth's moon is theorized to have been formed is by a huge object smashing into the Earth early in its history, blasting off a bunch of material from the Earth which eventually formed together into the moon.\n\nThis theory is supported by the fact that the moon is made up almost entirely of stuff found in the upper layers of the Earth's crust. If it was a captured body that had arrived from elsewhere, we would not expect it to be so similar to Earth. If it had formed alongside the Earth, we would also expect it to have some of the denser stuff found lower down in the Earth's mantle and core in a similar proportion to what we see on Earth. However, the moon has barely any of that stuff."
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8r3j96 | What is inside of an insect's exoskeleton? [biology] | What I am actually wondering is do insects have meat? If not, what is inside their shell, and what happens if it is cooked? | askscience | https://www.reddit.com/r/askscience/comments/8r3j96/what_is_inside_of_an_insects_exoskeleton_biology/ | {
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"If by meat you mean muscle, then yes. Insects have muscle tissue. _URL_0_, _URL_1_\nInsects are much smaller and lighter than anything we typically associate with having meat, so their muscular composition is tiny.",
"Insects have striated muscles as opposed to humans who have smooth and striated muscles. Smooth muscle is usually organ muscle while striated is for movement. Insects also have open circulatory systems so no vessels. The liquid in them is their \"blood\" and contains nutrients and metabolic waste. It is slightly more intricate than this but essentially, the action of pumping in their hearts and movement by the insect itself circulates the blood naturally."
]
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66r7cj | how does running improve your oxygen uptake capacity? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66r7cj/eli5_how_does_running_improve_your_oxygen_uptake/ | {
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"When you run you are doing what's called aerobic activity, meaning your respiration increases. But what doesn't change immediately is the hearts ability to pump more at a time during this activity. Over time your heart gets stronger and is able to pump more blood to your muscles over the same period of time. Red blood cells are what carry oxygen to your muscle cells and if the heart can pump more in one beat then more red blood cells can reach your muscle cells in a time effective manner. \n\nEdit: to my knowledge it doesn't affect your oxygen uptake efficiency just your heart strength",
"Respiration is a lung activity. Your lungs suck in oxygen and hemoglobin in your red blood cells grabs it. You can increase lung capacity to increase the amount of air you can breathe in.\n\n\nThis is where your heart comes in. It has to move the blood. So as you run and do whatever, your body thirst for oxygen so your breathing increases and your heart rate rises to pump more and more blood/oxygen to the rest of your body.",
"Physiologist here, some answers are correct some BS.\n\nTo understand how your cardiorespiratory fitness, or maximum oxygen uptake (VO2), increases after a period of running you have to know what this terms actually means. The VO2max is the maximum volume of oxgygen that is used by the body measured during incremental exercise and is expressed in milliliters of oxygen consumed per kilogram body mass per minute. In order to get the muscles moving, oxygen must be extracted from the air, diffused through the alveoli into the bloodstream, transported by red blood cells, while the heart pumps the blood around until the oxygen gets to the exercising muscles. The capacity of the body to do these things is reflected in the VO2max. You have to see the VO2max as a chain, where the weakest link determines the strength of the chain. \n\n\nAfter a period of aerobic training (running/swimming/cycling), the body adapts to the more oxygen demanding circumstances. I'll discuss the most important changes:\n\n- More efficient use of the lungs. Parts of the lungs aren't perfused by the bloodstream which creates a 'dead space'. This effectively reduces the volume of air where the body can extract oxygen out of. Prolonged periods of exercise cause the lungs to perfuse the dead space, virtually increasing the lung volume. Fun fact: where initially more ventilation is needed to provide the increased oxygen demand, the high breathing frequency is a result of the body wanting to get rid out of CO2 that builds up in the blood/muscles\n\n- Exercise places more stress on the heart. The main arteries to the exercising muscles dilate to facilitate blood flow to those muscles. As a result, the (diastolic) blood pressure drops so in order to maintain a normal blood pressure the heart has to pump more forcefully. On top of that, blood flow has to increase to provide the muscles with more oxygenated blood. The heart gets more muscular. The heart chambers also increase in dimensions, resultig in more blood to be pumped **per heartbeat**. This can be seen very clearly in endurance athletes, in contrast to bodybuilders (where the heart is very muscular and the chamber volume decreases). *Note:* a low heart rate is the result these changes, not the cause. But that's a story for another time.\n\n- The arteries to the muscles expand (vasodilation) due to increased friction forces of the flowing blood against the arterial wall, which is called shear stress. This shear stress causes the cells in the inner layer of the arteries (endothelial cells) to release nitric oxide (NO). Smooth muscle cells surrounding the arteries react to the NO and as a result, the arteries dilate. The sensitivity of the endothelial cells to shear stress increases after a few weeks of training.\n\n- There are a couple of muscle fiber types. One of them is type I /red muscle fibers. In short, this is the muscle type that you mainly use during endurance sports because they are heavily perfused and they mainly use oxygen as a source of energy. Training causes a increase in capillary density in the muscles, meaning that the muscles will be more perfused."
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10gmha | Ratio of Cavalry to Infantry in 19th Century Warfare? | I know a decent amount about ancient history. And from my general readings it seems like about 100 horsemen to every 1000 infantry. That is a very loose generalization by me, and would welcome edits. But I was wondering more specifically about the 1800s. By then, what amount of Cavalry actually used in battle?
I am playing a game, set in 1860s, and the Infantry unit is set at 12,000 men. And the Cavalry unit is at 6,000. To me that ration sounds ridiculously high, and I am sure it is. But I am having difficulty finding numbers to propose a better ratio that is more realistic.
I appreciate anyone who takes the time to answer this silly question to make my game play more authentic. Thanks. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/10gmha/ratio_of_cavalry_to_infantry_in_19th_century/ | {
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"It depends highly on the specific era. I will talk about what I know, which is Napoleonic Wars.\n\nThe ideal proportion was 6-7 foot infantry for each rider (Waterloo had 4:1!). This was mantained for the French even in the hard conditions of the Peninsula campaign. The spanish army, big but badly administrated, had a much smaller ratio. For example, they had 12:1 in Bailén and 29:1 (!) in Medina de Rioseco.\n\nI dont know about the ACW, I know the cavalry was much worse than in the NW, but it still was incredibly strong. 2:1 proportion sounds off though."
]
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1mm0d8 | Why didn't the Allies use ballistic shields when disembarking at Normandy? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1mm0d8/why_didnt_the_allies_use_ballistic_shields_when/ | {
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"Not practical at all. Lets do the math. Let's use [these dimensions](_URL_0_), 50 x 87 cm for the width and height of these hypothetical shields. To stop a full-power rifle round reliably you want 13mm of armor-grade steel. 50cm * 87cm * 13mm = 5655 cubic centimeters of material coming out to a roughly 98 pounds or so. That is a lot of weight to carry. That's going to significantly impede his fighting ability, as well as reducing the number of troops which can be ferried to shore per boatload. Now suppose you want to equip all 156,000 or so allied troops with these monsters. You're looking at just over 7600 tons of steel. All of that material could go into a lot of other things which are actually useful to the war effort-- weighing in at 33 tons, for example, you could make about 200 M4 tanks. \n\nThose numbers are all really *really* loose approximations, but they help to give you an idea. But really, the reasons we didn't use them then are the same reasons we don't use them now. Shields which are large enough to offer meaningful protection while being thick enough to protect against rifle fire are extremely heavy and cumbersome. The sort of shields you see used by police are only effective against pistol-caliber rounds and stuff like buckshot. It is possible to create shields that shrug off rifle fire, but they wind up being so heavy that the guy carrying them can't really do much *besides* that. ",
"Do you know what's beter than ballistic shields at stopping small arms and machine gun fire? Tanks. And the Allies planned on having tanks on all of the beaches during the early part of the landings. At every landing except for Utah and Omaha beaches most of the tanks that were sent ashore landed successfully and in the correct location, and significantly contributed toward the destruction of the German machine gun and artillery defenses. The major reason why the Utah and Omaha beach landings were so horrific for the allies is precisely because of the failure of the tanks to either reach shore or to land in the same location as the troops. It wasn't a matter of bad planning, per se, or of intentionally setting soldiers up to a nearly impossible task, where they were sure to be mowed down in the hundreds. It was what always happens in war, some parts of the plan didn't work as expected and difficulties resulted.",
"The Germans were firing full calibre rifle rounds from battle rifles (K98k) and machine guns (MG34 and MG42). Those rounds will punch through quite a bit more metal than one might think. When you see police carrying shields they're not for rifle rounds, they're for things such as pistol rounds. To carry a shield thick enough to stop a rifle round it's going to be quite heavy and that will slow you down and thus increase the chance that something else is going to get you such as artillery or you're going to be shot at so much that an unlucky shot is going to get you. \n\nNow, even if you did manage to get shields you're only going to be protecting your front and shots are going to be coming in from the sides and due to bullet drop from slightly above. Forming a tortoise would just present a mass target for artillery. \n\nSoldiers also carry a lot of weight as it is. Quite a few soldiers at Normandy drowned due to the weight they were carrying. If they went ashore with shields more would drown or they'd be the first thing a soldier struggling in the water would drop."
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8wezed | Do Native Americans who didn't have direct contact with the early Spanish explorers have oral history about the introduction of horses? Where did they think they came from? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/8wezed/do_native_americans_who_didnt_have_direct_contact/ | {
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"I'm not an expert on the arrival of horses on the Great Plains, but I do use similar sources of information to understand [the spread of epidemic disease](_URL_3_) into the center of the continent. While we imagine horses transforming Plains cultures completely before sustained European contact, the confluence of guns, horses, and European encroachment simply added to the dynamic changes already occurring. The tendrils of contact arrived unevenly, with some nations like the Osage managing to position themselves to limit the westward spread of firearms to their enemies while utilising horses spreading northwards from New Mexico. In Osage oral tradition this was a golden time of unparalleled influence, when they held unchallenged control over the Eastern plains in Missouri. For others, the story was different. Horses arrived roughly at the same time as contact for the Mandan in North Dakota. When Pierre de la Verendrye made first contact in 1738, the Mandan knew about horses, but had not yet started forming herds. They would later increase horse use as a hunting tool, but would remain mostly sedentary agriculturalists and form the hub of a vast trading network on the Northern Plains. Now, onto the written and oral history.\n\nNorthern Plains tribes (like the Lakota, Kiowa, Mandan, and Dakota) kept historical records in the form of Winter Counts. Winter Counts were a historical record, a list of year names representing the most significant events in the life of the band. Pictorial representations of that event served as a reminder, a kind of mnemonic device, for the keeper of the count to retell the history of the band. We know of 53 Winter Counts that together provide a historical record of the Northern Plains from 1682 to 1920. To better imagine the diversity of Winter Counts check out [Battiste Good’s (from 1821-ca. 1907)](_URL_0_), and [Sam Two Kills](_URL_2_) working on the Big Missouri Winter Count. \n\nBy compiling the Winter Counts together into a master narrative we can establish a chronology, cross-check errors, and be fairly certain the events depicted are accurate to roughly two years. This works well for my interests in epidemic disease spread, but the arrival of the horse often falls into the deeper history of the Plains. By 1675 horses spread from New Mexico onto the Southern Plains of Kansas, and into the Dakotas and Alberta by the 1750s. See [Battiste Good's entry from this early time](_URL_1_), when he simply states, “Found horses among the buffalo again and caught six.\" Horses appear to be a food source, not yet a mode of transportation, in the very earliest accounts, and were either found when out on hunts, or seen when visiting neighbors. The Smithsonian had a searchable online exhibit/database of Lakota Winter Counts, but it appears to have been taken down. Pity. I hope another expert can tell us more about horses in the Counts.\n\nOutside of Winter Counts, the Piegan Blackfeet first saw horses in the 1730s, when an enemy shot an arrow into a Shoshone's mount. \"Numbers of us went to see him and we all admired him.\" The dead pony \"put us in mind of a stag that had lost his horns\" (quoted in Fenn, p.134). The name for horses often indicated comparisons to known species. In Lakota *Sunkawakan* means sacred or powerful dog. For the Cheyenne the arrival of the horse was foretold by the prophet Sweet Medicine. \n\n > This animal will carry you on his back and help you in many ways. Those far hills that seem only a blue vision in the distance take many days to reach now; but with this animal you can get there in a short time, so fear him not. (quoted in Calloway, p.182)\n\nCheyennes reported seeing horses in the early 1700s and remembering the prophecy. \"He thought of the prophecy of Sweet Medicine, that there would be animals with round hoofs and shaggy manes and tails, and men could ride on their backs into the Blue Vision. He went back to the village and told the old Indians, and they remembered.\"\n\nFrom the Apaches to the Pueblos, Kiowas to the Caddos, Comanches to the Shoshonis, Shoshonis to the Crows and Nez Perces, and Arikara to the Lakota, trading partners helped spread horses throughout the West. While popular history assumes a total transformation, Lakota writer Joseph Marshall III reminds us that horses did not create Lakota culture, but it \"took it to levels never dreamed of\" (quoted in Calloway, p.180). The ability to ride, or carry heavier loads changed life in a multitude of ways, enriching life on the Plains. Pretty Shield, a Crow, recalled her grandmother's histories. In the old days when they traveled on foot and loaded packs on dogs, elders were often left behind. With the horse \"even the old people could could ride. Ahh, I came into a happy world. There was always fat meat, glad singing, and much dancing in our villages. Our people's hearts were then as light as breath-feathers\" (quoted in Calloway, p.272).\n\nSources:\n\nFenn, *Encounters at the Heart of the World: a history of the Mandan People*\n\nCalloway, *One Vast Winter Count: The Native American West Before Lewsis and Clark*\n\nCalloway, *First Peoples: a documentary survey of American Indian history*",
"Follow-up/background, and I apologize if this is a silly question. Did horses exist in the Americas prior to the Europeans? I keep finding conflicting answers.\n\n\nThank you! "
]
} | [] | [] | [
[
"http://askhistorians.tumblr.com/post/155036916460/battiste-goods-winter-count-1821-ca-1907",
"http://askhistorians.tumblr.com/post/155043374524/found-horses-among-the-buffalo-again-and-caught",
"http://askhistorians.tumblr.com/post/155026158240/sam-kills-two-works-on-the-big-missouri-winter",
"https://www.reddit.com/r/AskHistorians/comments/22fgyz/monday_mysteries_disease_and_medicine/cgmphuh/"
],
[]
] |
||
2ba5ix | Literacy of Muhammad | I have been told that Muhammad was illiterate, but I have also been told that he was relatively well educated after his first marriage. With all of the Pro-Islam/Anti-Islam websites out there it is tough to find a decent source to work this out. Is there just some confusion on my part? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2ba5ix/literacy_of_muhammad/ | {
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"You'll find some disagreement among historians. I hesitate in using the word literacy because the word carries connotations that don't apply in this time period. Being educated did not mean being literate as in knowing how to read and write. Educated people knew poetry, geneology, and stories of various tribes. A few people did know how to read and write but it was not common. It also did not indicate status, a slave might read and write while his owner can't. Anyway, I find it most likely that he could not read/write except maybe his name. There's little other than speculation beyond that. Also, I don't know of any reason why he would have received any type of education after marriage. The concept of formal education didn't exist and if anything, his marriage ended his need to be a traveling merchant.",
"One thing to bear in mind is that we know very, very little of Muhammad outside of the early Arabic historical tradition - in particular, the genre of prophetic biography called *sira*. It's impossible for us to say for certain, as we must be cautious in simply trusting this religious tradition. The people writing it down were later Muslims who were writing about their Prophet - for many of them, the most important person who had ever lived! It isn't far-fetched to believe they might have had a bit of \"bias\" when they were writing. \n\nThe point to keep in mind is that every Prophet that had come before Muhammad - the final prophet - in the Jewish/Christian/Islamic tradition had been given a miracle by God that they performed. Moses, for instance, had parted the Red Sea; Jonah had survived the whale. What was Muhammad's miracle? \n\nMuhammad's miracle from God was the holy Qur'an itself - his most perfect message, sent to a man who was illiterate - who didn't possibly have the ability to speak/write something so fine and so pure. It was a clear demonstration that he was God's messenger.\n\nDevout Muslims, of course, believe that this was how it was and it may well be the case. But imagine, for instance, that Muhammad was an extremely well-educated writer/poet/scribe. While the Qur'an isn't any less beautiful or important for Muslims if this is the case, it makes Muhammad's \"miracle\" a bit less impressive, no? "
]
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[],
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|
fa8az6 | I’m a Medieval English peasant. How much am I concerned with personal hygiene? | I keep seeing the film trope of the peasant covered in filth, apparently fine with it. However in my own life I am disgusted by unclean habits and smells, from myself and other people. Would a peasant be ok with it or are the “dirty peasant” tropes exaggerated? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/fa8az6/im_a_medieval_english_peasant_how_much_am_i/ | {
"a_id": [
"fiwyo4k"
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"text": [
"Dirty peasant tropes are indeed vastly exaggerated. While we might think an average medieval person a little grubby compared to the particularly germaphobic standards of our time, they still valued hygiene and cleanliness. I wrote a longer answer about it [here](_URL_2_). I also wrote a little bit about how a decline in the Roman style of *bathing* gets artificially conflated with a decline in *washing* [here](_URL_1_).\n\nYou might also enjoy /u/MikeDash's rebuttal of the idea that Elizabeth I only took four baths a year, which you can read [here](_URL_0_)."
]
} | [] | [] | [
[
"https://www.reddit.com/r/AskHistorians/comments/eshd9x/did_anyone_really_say_her_majesty_takes_a_bath/ffa4nxf",
"https://www.reddit.com/r/AskHistorians/comments/ccys40/conflicting_information_on_medieval_bathing/etqwizq",
"https://www.reddit.com/r/AskHistorians/comments/bqjfh7/what_was_the_reason_for_the_decline_of_basic/eo83nt6"
]
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|
j727p | Does draining water exhibit a spiral motion at or near the equator? | So today I've been learning about the coriolis force and I knew it was responsible for the rotational motion of water when it drains in a sink and that the direction of the force depends on which hemisphere one observes this in. I did not know until today that the coriolis force vanishes at the equator (and this is the reason no hurricanes form within 500 miles of the equator) so does this also mean that water simply drains without spiralling into the sink? | askscience | http://www.reddit.com/r/askscience/comments/j727p/does_draining_water_exhibit_a_spiral_motion_at_or/ | {
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" > So today I've been learning about the coriolis force and I knew it was responsible for the rotational motion of water when it drains in a sink and that the direction of the force depends on which hemisphere one observes this in\n\nThis is actually false. The coriolis force is basically nothing on the scale of your sink - small imperfections in your sink, or water being poured in off-centre dominate by a huge amount. I did hear of someone managing to actually see the effect of the coriolis force on a tub, by taking a perfect bowl several metres across and making sure the water had no currents before draining.\n\nSo if you drain at the equator, your sink and how you pour the water in has the dominant effect, just like anywhere else.\n\nHowever, what you learnt about hurricanes was right. And it's cool that you worked out that if the coriolis force controlled which way water drains, then water should drain straight down near the equator - there are tourist traps where they try to convince you that walking 2 metres on either side of the equator makes a significant difference...",
" > So today I've been learning about the coriolis force and I knew it was responsible for the rotational motion of water when it drains in a sink and that the direction of the force depends on which hemisphere one observes this in\n\nThis is actually false. The coriolis force is basically nothing on the scale of your sink - small imperfections in your sink, or water being poured in off-centre dominate by a huge amount. I did hear of someone managing to actually see the effect of the coriolis force on a tub, by taking a perfect bowl several metres across and making sure the water had no currents before draining.\n\nSo if you drain at the equator, your sink and how you pour the water in has the dominant effect, just like anywhere else.\n\nHowever, what you learnt about hurricanes was right. And it's cool that you worked out that if the coriolis force controlled which way water drains, then water should drain straight down near the equator - there are tourist traps where they try to convince you that walking 2 metres on either side of the equator makes a significant difference..."
]
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15mj8v | When the brain sends a signal to both hands, do the signals arrive at the exact same time? | When, for example, I tap my fingers, do they tap at the same time or is there some tiny micro delay between the 2 fingers, which only can be detected by sound analysis? | askscience | http://www.reddit.com/r/askscience/comments/15mj8v/when_the_brain_sends_a_signal_to_both_hands_do/ | {
"a_id": [
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"There is no magic in your neurons that guarantees *exactly* the same signal speed. Differences definitely occur, and show up easily in slow-motion video or other high-precision recording.\n\nHowever, there are coordinating neurons in your spinal cord that make it particularly easy for your brain to send a signal that the two symmetric body parts should attempt to move simultaneously."
]
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[]
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|
1nnvf0 | Why wasn't Johann Reichhart, a judicial executioner in Nazi Germany, charged with a single war crime for carrying out executions on behalf of Nazi Courts? | * He meticulously documented the details of carrying out executions of 2,876 people between 1939 and 1945.
* Many of the executed were innocent such as members of the White Rose movement sentenced to death for their opposition to Hitler.
* He was a Nazi party member.
| AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1nnvf0/why_wasnt_johann_reichhart_a_judicial_executioner/ | {
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"Firstly, he could not have been charged with a \"war crime\" because he didn't participate in the war and didn't execute POWs, but that's just semantics. \n\nAccording to his biography \"Tod durch das Fallbeil\" by Johann Dachs, he was arrested by American soldiers in 1945. They brought him to a cemetery and performed a mock execution on him. But they didn't jail him because they had better work for him. On behalf of the Americans he hanged 156 war criminals until 1946, when they didn't need him anymore and put him in the [internment camp Moosburg](_URL_1_), although he hoped he would get a milder treatmed due to his collaboration.\n\nOf course he was totally ostracized in the internment camp by the other inmates because he performed executions for the American occupiers. He tried to kill himself by slitting his wrists, but he was found early enough. Even in the hospital he got beaten up by Nazi inmates. The [denazifcation court](_URL_0_) declared him as \"belastet\" (Offender), which was the second highest category only below the the \"Major Offenders\" who could be executed."
]
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[
"http://en.wikipedia.org/wiki/Denazification#American_zone",
"http://en.wikipedia.org/wiki/Stalag_VII-A#Aftermath"
]
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|
1lypga | What was going on in Cuba when the Soviet Union collapsed? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/1lypga/what_was_going_on_in_cuba_when_the_soviet_union/ | {
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"The Special Period is pretty interesting. I know a bit about it from the food systems and energy perspective. Basically when the USSR collapsed Cuban oil supplies dried up. Cuban has a small amount of offshore oil but it's heavy oil and couldn't be refined or produced at rates that would satisfy demand. This had huge implications for agriculture which prior to the special period was largely done on the broadscale industrial model practised by the Soviets. As a result of the oil shortages fuel, pesticide and fertilizer was severely restricted and agricultural output collapsed. The average cuban lost about [5% to 25% percent of their body weight](_URL_1_) as a result of caloric restrictions. Food rations at the peak of the crisis were only about 1/5 of the normal amounts. Interestingly this had a number of long term health benefits including marked reductions in rates of diabetes. \n\nIn response there was a massive movement in towards urban farming and gardening. Vacant land was appropriated by gardeners and while initially illegal or at least legally ambiguous these private farming initiatives were eventually sanctioned by the cuban government. Semi-private co ops were allowed to produce and sell food on a quasi market system. Permaculture techniques (polyculture cropping and integrated animal systems) became quite common. Today 80% of Cuban food is produced with permaculture or organic methods. \n\n[There is a good documentary called the Power of Community here](_URL_0_)"
]
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"http://www.youtube.com/watch?v=L2TzvnRo6_c",
"http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2474886/"
]
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6391y0 | If there are 3 space dimensions and one time dimension, is it theoretically possible to have multiple time demensions and if so how would it work? | askscience | https://www.reddit.com/r/askscience/comments/6391y0/if_there_are_3_space_dimensions_and_one_time/ | {
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"Yes, we can consider spacetimes with any number of temporal or spatial dimensions. The theory is set up essentially the same. Spacetime is modeled as a smooth *n*-dimensional manifold with a pseudo-Riemannian metric, and the metric satisfies the Einstein field equations (Einstein tensor = stress tensor).\n\nA pseudo-Riemannian tensor is characterized by its signature, i.e., the number of negative quadratic forms in its metric and the number of positive quadratic forms. The coordinates with negative forms correspond to temporal dimensions. (This is a convention that is fixed from the start.) In general relativity, spacetime is 4-dimensional, and the signature is (1,3), so there is 1 temporal dimension and 3 spatial dimensions.\n\nOkay, so that's a lot of math, but it all basically means that, yes, it makes sense to ask questions like \"what does a universe with 2 time dimensions and 3 spatial dimensions look like?\" It turns out that spacetimes with more than 1 temporal dimension are very pathological. For one, initial value problems do not generally have unique solutions. There is also generally no canonical way to pick out 1 of the infinitely many solutions to the equations of physics. This means that predictability is impossible (e.g., how do you know which solution is the correct one?). Essentially, there is no meaningful physics in a spacetime with more than 1 temporal dimension.\n\n(Ultimately, the problems comes from the fact that allowing more than 1 temporal dimension allows the existence of closed timelike curves, i.e., time travel, even in perfectly regular spacetimes, like those with a flat metric. Regular metrics with CTC's do exist in GR, e.g., the Godel metric, but these metrics with CTC's generally do not correspond to anything reasonably physical, *or* the CTC's are hidden behind the event horizon of a black hole.)"
]
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16nf95 | Why are there Iroquois names and words all over Seattle? | I'm from the Midwest, and I've grown up with places named Seneca and Genesee. However recently I started noticing more and more places with out of state native american names here in Seattle. (Genesee Park and St. Seneca St. and i thought there was one more...)
I've done a little research with no good answers. The only other association I can only come up with is George Washington's past with the Iroquois, and considering he was "Town Destroyer" I didn't think it was in memorial to that. | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/16nf95/why_are_there_iroquois_names_and_words_all_over/ | {
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"To be fair, Seneca was the name of two major Roman philosophers.",
"Often it ends up not being named after Iroquois directly, but after *other* things that are named after Iroquois. Given the rise of Seattle (and other Pac NW cities) shortly after the time of expropriation of Iroquois landscapes, it might be logical that people moving west would take local names with them. For example, Genesee County in Colorado probably followed Genesee County, MI which followed Genesee County, NY. Heritage names that are out of place relative to their ultimate origin are after all quite common; George Washington was never anywhere *near* WA. I will, however, tell you that there are a lot of Midwest transplants in WA and OR, which may also explain the transplanted names.\n\n"
]
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11zlk1 | why is it that when i wiggle my finger in my belly button, i feel it in my penis? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/11zlk1/why_is_it_that_when_i_wiggle_my_finger_in_my/ | {
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"text": [
"I thought I was the only person that experiences this!",
"I have this same thing, but the lady version, and totally thought I was a weirdo. I'm glad other people experience this, even if we don't know why...",
"I know that feel.",
"Hmm... I don't feel an-oop! There it goes. Weird. I desire more knowledge.",
"A few years ago, in anatomy class, our teacher told us that there's a nerve linking the bellybutton to the bladder... ",
"How does it feel to know that, after just typing a few letters and hitting \"submit\", you've forced thousands of strangers to fondle their belly buttons?",
"How deep/hard does the finger need to go? Because I'm digging in and not feeling anything down here.\n\n/greatthingtotakeoutofcontext",
"As anyone who's ever had kidney problems can tell you, the nerves below your waist are unreliable when it comes to location. Basically, there's a lot of information to transmit, and not enough space for the wires.",
"I actually feel it in my ass",
"It's because the bellybuttons function is to keep the penis attached, much like a knot at the end of a rope to stop it from slipping through a hole, so that you can hang something heavy on it.",
"Finally! I asked my dad that once, when I was 7 or 8 and he laughed and said \"that's a funny way to masturbate\".\nI don't feel it in my penis, but my balls. It feels like someone is needling (is that a real word?) my balls. It isn't really a good feeling, I try to stay away from it.",
"Thank you for asking this question OP. I had been wondering this last week and couldn't find a good answer through google.",
"ITT: No one answering op or just speculating.",
"PLOT TWIST: OP is female.",
"You may want to see a doctor.",
"I have an outtie, does this affect my ability to feel my penis in my belly button?",
"So, I've never experienced this, but I can give a reason from Anatomy and Embryology. During development as a fetus, the testes originate right around the level of the abdomen near the belly button. Here, they develop nerves that run to the spinal cord at this level (vertebrae T10-12, if I remember correctly). During development, the testes move downward, travel through the inguinal canal (basically a small tunnel where your leg meets your abdomen), and descend into the testes. They remain connected to the spinal cord via the same nerves, the nerves just get longer. In the spinal cord, there's a network of nerves that integrate signals coming from the organs and the overlying skin at that area. Those signals, 'sensation from the testes' vs 'sensation from the belly button' remain mostly separate, but there are a few overlapping connections. Because we're not really used to feeling things from our internal organs, often times our brain interprets signals coming from them as coming from the same level as that sensation. In the case of the testes, this sensation is referred to the belly button area, so often pain from the testes occurs in the belly button area (this is called \"referred pain\"). I suppose it's also possible that the reverse could happen as well, that sensation from the skin can be referred to the internal organs.",
"I'm gonna go on a limb and say you're actually 5 and your father wanted to know as well so he posted the question?\n",
"Ahh fuck, I feel it in the anus. Now I have to poop. \n\nCurse you, OP.",
"It doesn't happen to me. ",
"Because that's not your belly button.",
"How many people immediatly tried this?",
"Did anyone else try this and not feel anything in their penis...?",
"Because you are a man. You will feel everything \"in your penis\"",
"And I thought I was unique... now I'm just a regular nobody again :(",
"Just lucky, I guess.",
"The reverse is also true; if you stick your finger in your penis hole it feels like it's in your bellybutton. Try it!"
]
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2dgfd8 | How many and what type of people migrated INTO East Germany/Eastern Europe during the Cold War? | I'm interested in emigration patterns throughout the USSR's lifecycle. I know many people ran BEHIND the Iron Curtain, but history seems to focus on the those running out. Who chose to live in the Soviet sphere, why did they, and when did they? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/2dgfd8/how_many_and_what_type_of_people_migrated_into/ | {
"a_id": [
"cjpbtvu"
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"text": [
"There was a book published recently on this topic, or very close it. The title is \"Burned Bridge\", with some subtitle. I'm on mobile right now, so I can't provide a better source. The goal of the book is to examine the formation of that border, to look at who moved in both directions and why, to examine why the border was created and who benefitted from it, and to show that it was not as simple as East restraining desperate people from fleeing to a prosperous West."
]
} | [] | [] | [
[]
] |
|
4ru7gv | Should I take ancient Chinese history with a pinch of salt because of The Mandate of Heaven? | [deleted] | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4ru7gv/should_i_take_ancient_chinese_history_with_a/ | {
"a_id": [
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"I'm not sure what you mean by saying \"But then I learned about the Mandate of Heaven.\" The \"Mandate of Heaven\" was a religio-political theory invented by the Zhou dynasty to justify its overthrow of the Shang dynasty, and later adopted by subsequent dynasties for their own political purposes (as well as by dissidents to support their own criticism of Chinese imperial regimes)."
]
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[]
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|
dzpori | can a chicken hatch from a non fertilized egg? | a friend of mine told me there is a little chance that in the right conditions a chicken will hatch from a non fertilized egg, is he right? if he is how is that possible? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dzpori/eli5_can_a_chicken_hatch_from_a_non_fertilized_egg/ | {
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"text": [
"No because an unfertilised egg only has half the number of chromosomes - genes compared to a live chicken.\nIt’s essentially like the egg that human females have in our ovaries. You need the other half set of genes from a males to create a living organism",
"This question led me to search how chickens mate and now I'm cracking up. I guess this is where the classic chicken dance comes from.\n\n\"A rooster often employs a type of foreplay by prancing around the hen and clucking before mounting her. The transfer of sperm happens quickly without the penetration normal in mammal mating. The cloaca, or vent, of the male and female touch and sperm are exchanged.\"",
"The general phenomenon is called parthenogenesis, which happens rarely in chickens and I don't think viable hatches are known. They do sometimes happen from other birds I think. Various other species do this more often, right up to some species of lizards that always lay fertile but unfertilized eggs.\n\nAs for why it happens, it varies from place to place but generally speaking the egg, through some screw-up of cell division during meiosis, produces an egg with two sets of DNA instead of one. This egg can then divide and develop as though its second set of DNA had come from a sperm. However, development often fails due to genetic abnormalities."
]
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|
54w7hz | why do governments fund private schools? | What exactly are they paying for? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/54w7hz/eli5_why_do_governments_fund_private_schools/ | {
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"It is cheaper to pay a private school than to build a school for example for the students that have a public school far from home.",
"They are paying for the teachers and the buildings and the books and so on.\n\nWhen the government fund private schools, it's because the point isn't to have public schools, but public *education* -- that is, the idea is that the state pays for the education, and not necessarily directly employ those doing it.",
"What do you mean by a private school? Are you in the US?\n\n\nIn the US, a \"public school\" is one run and financed by a local government. There's a variation of that called a \"charter school\", where it's run by a private company but financed by the government. Then there are \"private schools\", which are not financed by the government.\n\n\nIn general, public schools have no admission criteria ie: everyone can enter. Private schools can admit who they want, and usually have academic and/or financial criteria for admission. Charters can vary, but generally they seem to admit students on a lottery basis.\n\n\nFinancing in this case generally means active support, like paying tuition or providing loans. In general the government does not provide active financial support private schools in the US. They do get tax breaks as a non-profit, though.\n"
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6hovkj | how are rappers being inducted into the "rock n' roll hall of fame"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6hovkj/eli5_how_are_rappers_being_inducted_into_the_rock/ | {
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"Agreed: Rcok n' Roll music is something you can go \"cha cha cha, cha cha cha, rock, step\" to. Closely related to swing, jive, and cha-cha.\n\nRappers should be inducted into the hip-hop hall of fame, as they share a history with soul/hip-hop and dance hall, not rock and roll.\n\nThen again, there are all sorts of pop hits that are inducted into the rock and roll hall of fame, despite them having nothing to do with rock and roll. Rappers are hardly the first.",
"The Rock and Roll Hall of Fame has essentially morphed into the Music Hall of Fame. I guess this happened because they are the only game in town. There is no Rap HOF or Pop HOF. "
]
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[],
[]
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||
4bzhkl | When Mongolia was a communist state, how did the government portray Genghis Khan? Did they ever manipulate his image for propaganda purposes? | AskHistorians | https://www.reddit.com/r/AskHistorians/comments/4bzhkl/when_mongolia_was_a_communist_state_how_did_the/ | {
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"The government (and by extension, Moscow), tried to suppress any glorification of Genghis as a threat to the system.\n\nThis is from Alan Sanders's \"Historical Dictionary of Mongolia\":\n\n > In the 20th century, the demands of communist ideology came into direct conflict with historical tradition. After the onslaught against Lamaism in the 1930s and the hardships of World War II, at a time of East-West confrontation when Stalinism was at its zenith, the party returned to matters of ideological reliability. In a resolution issued in 1949, the Politburo of the ruling Mongolian People's Revolutionary Party (MPRP) noted in the teaching of history and literature in schools a tendency \"to deviate into bourgeois nationalist views.\" This was allegedly due to the lack of textbooks written from the Marxist-Leninist viewpoint and confusion among intellectuals over the difference between national pride and \"bourgeois nationalism\"-boasting about the conquests of Genghis Khan and idealizing Mongol \"feudalism\" to the point of negating the achievements of the people's revolution in Mongolia, that is, the legitimacy of the party itself. \n\nThat said, it seems that the Mongolian leadership still viewed him as a national hero, and during the Khrushchev Thaw an attempt was made in 1962, the 800th anniversary of his birth, to erect a statue (apparently the first statue of Genghis Khan ever erected by Mongols) of him in Deluun Boldog, Khentii (where Genghis was alleged to have been born).\n\n > Daramyn Tomor-Ochir, a member of the MPRP Politburo and Secretariat, was given the task of organizing the national celebrations, including the unveiling of a monument at Genghis Khan's supposed birthplace at Deluun Boldog, with a speech by a leading historian for the occasion on 31 May and the publication of a set of Genghis Khan anniversary post-age stamps. At about this time, however, Genghis Khan was attacked in the CPSU (Soviet Communist Party) newspaper, Pravda, as a \"reactionary\" whose \"Mongol-Tatar yoke\" of tenor and extortion had laid waste to Russia. In a damage-limitation exercise, the MPRP Politburo. headed by First Secretary Yumjaagiin Tsedenbal quickly issued a new and negative evaluation of the founder of the Mongol state and deprived Tomor-Ochir of his party posts. The new official view of Genghis Khan was that, in founding the Mongol state, he had played a positive role in unifying the divided tribes. \"But all his further activity was doubly reactionary and aimed at the seizure of foreign lands, the mass annihilation of the peoples of enslaved countries and the destruction of their material and cultural values.\" Thus to \"deny or insufficiently emphasize the reactionary nature of Genghis Khan's activities is in essence to deviate from the party's position of principle and to encourage nationalism.\"\n\nOf course since the revolution in 1990 Genghis became ubiquitous. The former Sukhbaatar Square (named after one of the main leaders of the 1921 communist revolution) in Ulaanbaatar lost Sukhbaatar's mausoleum in 2005, a monument to Genghis Khan and the Mongol Empire built in its place, and even lost its name and in 2013 was officially renamed Genghis Khan square.",
"I seem to remember hearing somewhere that during the Soviet period a conference of scholars was raided, causing one scholar to escape with the Secret History of the Mongols scrolls into China. Is there any truth to this? Does anyone have any sources about it if true?"
]
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[],
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150f3w | Cambodian/Vietnamese Conflict - Various Questions | 1) Was Cambodia bombed by the Nixon Admin in order to avert the PolPot uprising? If so, why was it stopped? Given the genocide, it seems this was far more honorable than the case for Vietnam.
2) What was Cambodia National Army's relation to North and South Vietnam? What was PolPot's relation to North and South Vietnam?
3) How were PolPot's soldiers recruited? | AskHistorians | http://www.reddit.com/r/AskHistorians/comments/150f3w/cambodianvietnamese_conflict_various_questions/ | {
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"Let me start with the first question.\n\nNo, Cambodia was not bombed because of that. Cambodia was bombed due to the North Vietnamese bases at the border, and continued to be so due to North Vietnam. By the time the genocide actually started with the take over in 1975, the bombing had stopped.\n\nThe second one, which is really two question, is far more complicated. Pol Pot's relation to North Vietnam is one that needs to be explored in a far more deeper sense than I can offer at the moment (without any type of references that I can go back to). Pol Pot, if anything, personified the Cambodian minority complex regarding its big brother Vietnam. He was an ally in name only to North Vietnam and was very mistrusting of them and their own interests in the Khmer Rouges. \n\nNow, regarding the recruitment of Pol Pot's irregular soldiers: They were recruited through the means of attraction. Propaganda means, so to speak. it was all about trying to portray the government as the enemy of the ordinary peasant and then channeling that through recruitment into the armed forces. Not many peasants listened or took these messages seriously except those directly affected by the government or American bombings. After King Sihanouk sided with the Khmer Rouge, plenty of peasants joined up because of the wish to reinsert Sihanouk back to the throne."
]
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[]
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|
17gw2u | How factual was Neil DeGrasse Tyson when he says Hamid al-Ghazali's work was the primary influence on Islamic society to reject scientific temper during 12th century? | I was paraphrasing his statement from this video.
_URL_0_
| AskHistorians | http://www.reddit.com/r/AskHistorians/comments/17gw2u/how_factual_was_neil_degrasse_tyson_when_he_says/ | {
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"If memory serves correct, I am not familiar with Hamid al-Ghazali, though I do know that he rejected Neoplatonist and Aristotelian philosophies as being incompatible with Islam, the Mongol Sack of Baghdad, the Collapse of the Fatimid Caliphate, and the Spanish Reconquista were the main forces that drove Islam away from scientific advancement.\n\nMost of the Middle also stagnated under the Ottomans. Originally the Ottomans were one of the most advanced and sophisticated states in Europe, being heirs to both Byzantium and Islam, but their methods of consolidation later stalled and they became the proverbial \"sick man\" of Europe. They rejected many western ideas and curtailed the spread of the printing press, and gradually their technology and science became eclipsed.\n\n\nEDIT: Put bluntly, it bothers me to hell when popularizers of science skew the history and philosophy of science to fit their own intellectual viewpoints. This bothers me because he's going for a \"this happened before, and it could happen again\" to burn down Young Earth Creationism. Now, while I think that Rationalism, Science, and Empiricism, as well as accurate public education, are essential to a modern society, his claim that Al-Ghazali is the reason why Muslims only make up 1-2 Nobel Prize winners total is completely baseless. Put bluntly, almost nothing has such a direct causal chain from the 12th Century. It's a complete whitewash of the major struggles and triumphs that have occurred in the Middle East since the Collapse of the Ottoman Empire and before.",
"I dislike the point he puts forward here as he misinterprets the point of Ghazali's work. Ghazali was a skeptic, rejecting the current courses of Islamic philosophy because he believed it should have its roots in Islam rather than being based on the works of Plato and Aristotle. He was more inward looking, but from what I've read he was not anti-scientific as NDT suggests here. True, we might perhaps argue that the _followers_ of Ghazali later interpreted his writings as anti-scientific and based their actions on such interpretations but if that's you're argument then you can't lay the blame squarely on Ghazali.\n\nIf you want to point fingers at philosophers there are probably 'better' choices, like the 12th century Ibn Taymiyyah, the forefather of what centuries later would be Wahhabism (the dominant creed in modern Saudi). But even this is flawed, as with the case of Ghazali you're ignoring the context of the philosopher's times and environments which brought these ideas about. As cfmonkey45 says, it's the decline/collapse of scientific centres such as Baghdad and Cordoba likely had a larger impact on Islamic science than any one philosopher's work.",
"What everyone else said. He was wrong.\n\nSome old discussions (which include quotes from Al-Ghazali himself):\n\n_URL_1_\n\n_URL_0_ (blog post that has good quotes by some redditors)",
"al-Ghazali has become a popular target as the watershed for the \"end\" of the Islamic \"golden age.\" It is certainly true that, as cfmonkey45 has said, al-Ghazali strongly rejected Neoplatonist and Aristotelian philosophy that was popular amongst certain sects of Islam - the [Mu'tazilites](_URL_1_) specifically. The Mu'tazilites had gained significant standing in the Islamic world when they gained official court patronage in the early 'Abbasid period, but they had been on the wane already by the time *The Incoherence of the Philosophers* debuted. It is true, though, that the work of al-Ghazali helped to kill off this ideological school. \n\nAs I mentioned, al-Ghazali has become a popular target over the last decade or so for the decline of Islam with regards to science, but there is an excellent - and extremely readable - argument made by Arabist Jamil Rageb for why this is simply false. Rageb also cites in the article some of these attempts to lay the blame at the feet of al-Ghazali, so that you can have a bit more of a look yourself. \n\nThe article: [\"When Did Islamic Science Die? And Who Cares?\"](_URL_0_)\n\nFor the layman, science doesn't simply die out after al-Ghazali's lifetime at all, and Rageb cites a number of significant developments in the sciences that occurred firmly *after* al-Ghazali's death. Examples of this include the discovery of the pulmonary transit,while there was a huge amount of scientific and philosophical texts that continued to be produced and created in the Islamic world centuries after al-Ghazali had died.\n\n**Tl;DR** Science is alive and well in the Islamic realm long after the death of al-Ghazali. Suggestions that science occurred \"in spite of Islam\" and not because of it belong to a long modern discourse of Orientalist scholarship. "
]
} | [] | [
"http://www.youtube.com/watch?v=fDAT98eEN5Q#t=6m40s"
] | [
[],
[],
[
"http://difaa0.wordpress.com/2011/03/03/did-al-ghazali-stifle-science-and-innovation-in-the-muslim-world-re-orthodox-islam-and-asharis-vs-mutazilah-in-science/",
"http://www.reddit.com/r/PhilosophyofScience/comments/q9rzn/daniel_dennett_there_is_no_such_thing_as/c3w7t6a"
],
[
"http://islamsci.mcgill.ca/Viewpoint_ragep.pdf",
"http://en.wikipedia.org/wiki/Mu%27tazila"
]
] |
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