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 International Skeptics Forum Setting the record straight on Aristotle

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 5th March 2019, 06:21 PM #41 JimOfAllTrades Muse   Join Date: Aug 2011 Posts: 508 Hans has already posted from Aristotle's writings: Originally Posted by HansMustermann Anyway, let's look at what Aristotle himself wrote, as, you know, the definitive source of what he did write: http://www.filosofia.unimi.it/zucchi...%20Physics.pdf Specifically, Book 4, chapter 8, which even starts with setting out to disprove the vacuum, and does exactly the argument I mentioned above. We see the same weight or body moving faster than another for two reasons, either because there is a difference in what it moves through, as between water, air, and earth, or because, other things being equal, the moving body differs from the other owing to excess of weight or of lightness.It take some mind contortions to NOT interpret the above as saying plainly that heavier things fall faster. Let the speed have the same ratio to the speed, then, that air has to water. Then if air is twice as thin, the body will traverse B in twice the time that it does D, and the time C will be twice the time E.That is flat out wrong. But it gets better: We see that bodies which have a greater impulse either of weight or of lightness, if they area like in other respects, move faster over an equal space, and in the ratio which their magnitudes bear to each other. Therefore, they will also move through the void with this ratio of speed.This one EXPLICITLY not just says flat out that heavier things move faster than lighter things, but he tells you that the speeds are in the same ratio as the weights. It also spells it out that the same would apply in a void. That does seem pretty clear to me that he thought things would fall with a speed proportional to the weight. Unless I'm way off on my density estimates any metal available to them at the time would have been at least 10 times heavier than any wood. Given that, his math says to me that a metal spear should be falling at 10 times the speed of a similar size & shape wooden spear. It's true that a metal spear would hit the ground first due to air resistance. But in my estimation the difference between a two or three pound wooden spear and a 10 pound metal spear would be very little. Both have very little drag due to very small cross sections with respect to a vertical drop. I'd guess the difference would be so small as to be virtually unnoticeable to the naked eye, and nowhere near proportional to their weights.
 5th March 2019, 06:50 PM #42 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by JimOfAllTrades That does seem pretty clear to me that he thought things would fall with a speed proportional to the weight. Yes, through a medium. And it is true, as I have pointed out. Quote: Unless I'm way off on my density estimates any metal available to them at the time would have been at least 10 times heavier than any wood. Given that, his math says to me that a metal spear should be falling at 10 times the speed of a similar size & shape wooden spear. You will have to point me to the maths you are talking about. As I have already said I can't find where Aristotle said "If X is A time heavier than Y then X will fall then times faster than Y". Quote: It's true that a metal spear would hit the ground first due to air resistance. Which all that Aristotle said Quote: But in my estimation the difference between a two or three pound wooden spear and a 10 pound metal spear would be very little. Both have very little drag due to very small cross sections with respect to a vertical drop. I'd guess the difference would be so small as to be virtually unnoticeable to the naked eye, and nowhere near proportional to their weights. Of course it would be proportional to their weights. Not in a direct ratio, but proportional. There is a difference. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 5th March 2019, 07:25 PM #43 JimOfAllTrades Muse   Join Date: Aug 2011 Posts: 508 Originally Posted by Robin Of course it would be proportional to their weights. Not in a direct ratio, but proportional. There is a difference. Assuming the quote posted is correct it actually does say "and in the ratio which their magnitudes bear to each other". The straightforward reading of that would certainly seem to mean that for similar size and shape objects the falling speeds through a medium would be in the same ratio as their weight.
 5th March 2019, 07:28 PM #44 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by JimOfAllTrades Hans has already posted from Aristotle's writings.... And I have also pointed out that when he says "It also spells it out that the same would apply in a void" he is wrong. The very next sentence after the ones he quotes makes it clear that Aristotle is saying that this would not apply in a void and says why. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 5th March 2019, 07:32 PM #45 JimOfAllTrades Muse   Join Date: Aug 2011 Posts: 508 Originally Posted by Robin And I have also pointed out that when he says "It also spells it out that the same would apply in a void" he is wrong. The very next sentence after the ones he quotes makes it clear that Aristotle is saying that this would not apply in a void and says why. I haven't said anything about objects falling through a void.
 5th March 2019, 07:58 PM #46 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by Robin And I have also pointed out that when he says "It also spells it out that the same would apply in a void" he is wrong. The very next sentence after the ones he quotes makes it clear that Aristotle is saying that this would not apply in a void and says why. If you go to the Greek, the word is λόγον, which can mean ratio, but can also be rendered as "relation, correspondence, proportion", so I think you are trying very hard to contrive him being wrong about this. http://logeion.uchicago.edu/%CE%BB%C...B3%CE%BF%CF%82 __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 5th March 2019, 08:15 PM #47 JimOfAllTrades Muse   Join Date: Aug 2011 Posts: 508 Originally Posted by Robin If you go to the Greek, the word is λόγον, which can mean ratio, but can also be rendered as "relation, correspondence, proportion", so I think you are trying very hard to contrive him being wrong about this. http://logeion.uchicago.edu/%CE%BB%C...B3%CE%BF%CF%82 I don't think I'm trying particularly hard, just going with what seems to me to be the simplest reading of the quote. Proportion instead of ratio does make a difference, no doubt about it. But my point was that dropping a metal spear and a wooden spear would almost certainly show essentially zero difference in falling time from any relatively low height. It seems to me that experimentation at the time should have shown that with many materials of different weights there was no difference (because they didn't correctly understand terminal velocity). I would think these results should have affected his theory. Last edited by JimOfAllTrades; 5th March 2019 at 08:22 PM. Reason: oops, accidently deleted a paragraph before posting.
 5th March 2019, 08:20 PM #48 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Note that when Aristotle wants to be explicit about a proportion he will say so, for example here is where Aristotle talks about the relationship between force, weight and speed. Quote: Now since wherever there is a movent, its motion always acts upon something, is always in something, and always extends to something (by 'is always in something' I mean that it occupies a time: and by 'extends to something' I mean that it involves the traversing of a certain amount of distance: for at any moment when a thing is causing motion, it also has caused motion, so that there must always be a certain amount of distance that has been traversed and a certain amount of time that has been occupied). then, A the movent have moved B a distance G in a time D, then in the same time the same force A will move (1/2)B twice the distance G, and in (1/2)D it will move (1/2)B the whole distance for G: thus the rules of proportion will be observed. Again if a given force move a given weight a certain distance in a certain time and half the distance in half the time, half the motive power will move half the weight the same distance in the same time. Let E represent half the motive power A and Z half the weight B: then the ratio between the motive power and the weight in the one case is similar and proportionate to the ratio in the other, so that each force will cause the same distance to be traversed in the same time. Physics Book VII Part 5 Here is is talking about an object being moved by an external force and as far as I can see this is correct. In fact it is a pretty good first approximation of Newton's second law of motion. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" Last edited by Robin; 5th March 2019 at 09:31 PM.
 5th March 2019, 09:24 PM #49 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by MRC_Hans Galileo evolved evolved our knowledge of physics beyond that of Aristotle. Just as Aristotle evolved our knowledge of physics in his time and Archimedes evolved it beyond that of Aristotle and Newton etc evolved it beyond that of Galileo and so on. Quote: That's how things go. Who said it wasn't? Quote: Does it matter exactly how details were? Yes, I think it matters whether the things we believe about history are true or false. Quote: The important difference is that Galileo based his deductions on experimental evidence. And Aristotle, 2,000 years earlier, said explicitly that our knowledge of the world must be based on an inductive process using empirical data. He said many times that any theory which contradicts the observations must be wrong. I don't know why that is regarded as unimportant. But he did not design experiments explicitly to test theories. That came later. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 6th March 2019, 12:17 AM #50 HansMustermann Penultimate Amazing   Join Date: Mar 2009 Posts: 15,590 Originally Posted by Robin And I have also pointed out that when he says "It also spells it out that the same would apply in a void" he is wrong. The very next sentence after the ones he quotes makes it clear that Aristotle is saying that this would not apply in a void and says why. Not really, but that's the problem when you ONLY read the next sentence and run with that. The next sentence is part of an ad absurdum to show that a void can't exist, and that's BECAUSE the same would apply to a void and lead to an absurd result: an infinite speed. So, again, if you want to defend Aristotle, then READ Aristotle, don't just quote-mine. __________________ Which part of "Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn" don't you understand?
 6th March 2019, 12:26 AM #51 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by metacristi Or in the words of Gerard Holton: According to Aristotle, a theory that merely describes and predicts the facts of observation, no matter how accurately, is not good enough: It must also give them meaning in a wider sense, by showing that the facts are in accord with the general postulates of the whole philosophical system. That is more or less true of any scientist. They are rarely content with simply being able to predict stuff, not even the ones who say they are. They all want to know what breathes fire into the equations in one way or another. For the most part what Holton says about Aristotle is pretty much on the money and I don't think it really contradicts anything I have said here. One place Holton goes wrong is his equation which he says is implied by Aristotle's words. He says that the implied equation is "v=k(W/R)" where k is some suitable constant of proportionality and v is velocity, W is weight and R is resistance.. But the problem is that Aristotle does not say it is the weight per se, but the ability of the weight to divide the resisting medium. So if the resistance of the medium is negligible then the influence of weight on speed should also be negligible. As Aristotle says, if there were no resistance from the medium then the difference of weight would have no influence on the speed at all. But in Holton's equation a decrease in the resistance clearly makes weight have a greater influence on the speed and that is not what Aristotle says. In order to be consistent with what Aristotle says, the equation must satisfy: 1. As resistance increases speed decreases 2. As weight increases speed increases 3. As resistance goes to zero then the influence of weight on speed must also go to zero. So the equation is more likely to be something like v=k-p(R/W) with k and p suitable constants and v is velocity, W is weight and R is resistance of the medium. That would satisfy all three. But Aristotle also mentions that the speed of a falling object increases the longer it falls, so you would have to have time in there, so it might be something like "v=(k-p(R/W))t" Of course if Aristotle had actually written out this as a law he would have realised that it spoils one of this arguments against the void. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 6th March 2019, 12:39 AM #52 HansMustermann Penultimate Amazing   Join Date: Mar 2009 Posts: 15,590 Again, if you want to defend Aristotle, then READ Aristotle, don't just make up whatever bullcrap serves your silly CT. The whole argument against a void -- well, the one he makes there; he has several -- is that basically speed would become infinite in a void. That doesn't work with your silly equation, silly. Yes, YOU would write the equation that way. But that's not what Aristotle wrote. At that point you're no longer defending Aristotle, you're defending your own re-imagining Aristotle. __________________ Which part of "Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn" don't you understand? Last edited by HansMustermann; 6th March 2019 at 12:45 AM.
 6th March 2019, 12:43 AM #53 HansMustermann Penultimate Amazing   Join Date: Mar 2009 Posts: 15,590 Originally Posted by Robin That is more or less true of any scientist. They are rarely content with simply being able to predict stuff, not even the ones who say they are. They all want to know what breathes fire into the equations in one way or another. But that extra stuff is not science until it actually has the stuff that it predicts. It's called Occam's Razor. If your stuff that breathes fire isn't actually predicting anything new, it's not actually a part of the theory, it's just your own silliness. And if it does, then it becomes part of that which is "simply able to predict stuff". __________________ Which part of "Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn" don't you understand? Last edited by HansMustermann; 6th March 2019 at 01:15 AM.
 6th March 2019, 04:09 AM #54 David Mo Illuminator     Join Date: Aug 2012 Location: Somewhere on the Greenwich meridian Posts: 4,224 As far as I know, Galileo is basically facing Aristotelian physics, not exactly Aristotle. He goes so far as to accuse the Aristotelians of not having read Aristotle directly. Galileo's superiority over his rivals lies in the synthesis of mathematics and controlled experimentation. The latter was alien to Aristotle himself, who limited himself to observations and filled them with his peculiar metaphysical beliefs. In this, Galileo was very superior and therefore his system, corrected and increased, ended up becoming modern science.
 6th March 2019, 06:11 AM #55 Crossbow Seeking Honesty and Sanity     Join Date: Oct 2001 Location: Charleston, WV Posts: 12,711 Originally Posted by Robin The experiment I propose sets up just exactly this scenario which you claim is quite incorrect. I take an iron ball and a polystyrene ball and drop them from a height of ten metres through the same medium (ie air), which will land first? If one cannot negate the effects of air resistance, then the iron ball would land first. Just as if one were to drop a sheet of paper and a crumpled up piece of paper, then the crumpled sheet would land before the intact sheet. I still do not understand what is so unclear for you because the effects of air resistance on falling bodies has been well understood for at least the last few hundred years. __________________ On 22 JUL 2016, Candidate Donald Trump in his acceptance speech: "There can be no prosperity without law and order." On 05 FEB 2019, President Donald Trump said in his Sate of the Union Address: "If there is going to be peace and legislation, there cannot be war and investigation." On 15 FEB 2019 'BobTheCoward' said: "I constantly assert I am a fool." A man's best friend is his dogma.
 6th March 2019, 03:11 PM #56 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by HansMustermann Again, if you want to defend Aristotle, then READ Aristotle, don't just make up whatever bullcrap serves your silly CT. Wow, you are really getting upset over this aren't you? My quotes all come from Aristotle. Here is a hint for you. When you quote Aristotle, don't deliberately cut off the quote before the sentence that contradicts what you are saying about Aristotle. Quote: The whole argument against a void -- well, the one he makes there; he has several -- is that basically speed would become infinite in a void. That doesn't work with your silly equation, silly. You really are upset aren't you? Quote: Yes, YOU would write the equation that way. But that's not what Aristotle wrote. At that point you're no longer defending Aristotle, you're defending your own re-imagining Aristotle. As Holton pointed out, Aristotle didn't write mathematical expressions as such. So he wrote an equation that he said reflected what Aristotle had claimed. I pointed out that Holton's equation that contradicted what Aristotle claimed and rewrote his equation in a way that more accurately reflected what Aristotle had said. And I gave my reasons in detail, which you ignored in favour of some childish name calling. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 6th March 2019, 03:13 PM #57 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Again, I wonder at what the Aristotle haters are saying here. Aristotle claimed that heavier things fall faster through a medium because they have a greater force to divide that medium Heavier things do fall faster through a medium for more or less the reason Aristotle said. Which of these two things are you denying??? __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 6th March 2019, 03:18 PM #58 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by Crossbow If one cannot negate the effects of air resistance, then the iron ball would land first. Just as Aristotle claims. So where is Aristotle wrong? Quote: I still do not understand what is so unclear for you because the effects of air resistance on falling bodies has been well understood for at least the last few hundred years. I don't get what you don't get about what I am saying. Aristotle said that for objects falling through a medium like air, the heavier object will fall faster due to it having a greater force to divide the medium. It is true, as someone has finally admitted that for objects falling through a medium like air, the heavier object will fall faster for reasons that are more or less as Aristotle said. And yet you say that this claim of Aristotle's is wrong. You don't see what I don't understand about your position? You are agreeing that Aristotle is correct and also saying that Aristotle is wrong. What don't you get about that? __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 6th March 2019, 03:22 PM #59 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by David Mo As far as I know, Galileo is basically facing Aristotelian physics, not exactly Aristotle. He goes so far as to accuse the Aristotelians of not having read Aristotle directly. And the same thing applies to Galileo, as I pointed out. The part Galileo cites as a direct quote from Aristotle doesn't appear in anything Aristotle wrote. Probably not Galileo's fault, there was a lot of pseudo-Aristotle around at the time. Quote: Galileo's superiority over his rivals lies in the synthesis of mathematics and controlled experimentation. The latter was alien to Aristotle himself, who limited himself to observations and filled them with his peculiar metaphysical beliefs. One of his peculiar metaphysical beliefs is that scientific knowledge of the world must be based on an inductive process over empirical data, not deductive logic over assumed postulates. That one turned out rather well, don't you think? __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 6th March 2019, 03:25 PM #60 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by HansMustermann Again, if you want to defend Aristotle, then READ Aristotle, don't just make up whatever bullcrap serves your silly CT. Can we have an end to your lie that I haven't read any Aristotle. It is pretty obvious that I have read a good deal more of Aristotle than you ever have. Remember you thought that Aristotle based his claim about teeth on postulates rather than incorrect observations? And you didn't appear to know about his very careful observations of dissected bird eggs at various stages of development. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" Last edited by Robin; 6th March 2019 at 03:26 PM.
 6th March 2019, 03:29 PM #61 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by HansMustermann Yes, YOU would write the equation that way. But that's not what Aristotle wrote. At that point you're no longer defending Aristotle, you're defending your own re-imagining Aristotle. Here is what I said would have to be the case to be consistent with what Aristotle wrote: Quote: In order to be consistent with what Aristotle says, the equation must satisfy: 1. As resistance increases speed decreases 2. As weight increases speed increases 3. As resistance goes to zero then the influence of weight on speed must also go to zero. Be specific for once and tell me which one you disagree with. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 7th March 2019, 05:58 AM #62 Crossbow Seeking Honesty and Sanity     Join Date: Oct 2001 Location: Charleston, WV Posts: 12,711 Originally Posted by Robin Just as Aristotle claims. So where is Aristotle wrong? Aristotle did not properly account for the effects of air resistance on falling bodies. Quote: I don't get what you don't get about what I am saying. Aristotle said that for objects falling through a medium like air, the heavier object will fall faster due to it having a greater force to divide the medium. It is true, as someone has finally admitted that for objects falling through a medium like air, the heavier object will fall faster for reasons that are more or less as Aristotle said. And yet you say that this claim of Aristotle's is wrong. You don't see what I don't understand about your position? You are agreeing that Aristotle is correct and also saying that Aristotle is wrong. What don't you get about that? Again, I still fail to see what has you so terribly confused. Aristotle was wrong about his ideas concerning the motion of falling bodies, and that should be simple enough to understand. __________________ On 22 JUL 2016, Candidate Donald Trump in his acceptance speech: "There can be no prosperity without law and order." On 05 FEB 2019, President Donald Trump said in his Sate of the Union Address: "If there is going to be peace and legislation, there cannot be war and investigation." On 15 FEB 2019 'BobTheCoward' said: "I constantly assert I am a fool." A man's best friend is his dogma.
 7th March 2019, 08:49 AM #63 HansMustermann Penultimate Amazing   Join Date: Mar 2009 Posts: 15,590 Originally Posted by Robin Here is what I said would have to be the case to be consistent with what Aristotle wrote: Be specific for once and tell me which one you disagree with. I disagree with this simple issue: it's YOUR equation, not what Aristotle actually wrote. Yes, you could take his observations and arrive at a more correct formula. Sure. But that's YOU doing it, not Aristotle. It's like saying that Marx didn't REALLY propose Communism, because when _I_ look at his premises, _I_ can see that Keynesian Economics are a better solution to all that. Well, sure, but that's clarifying how _I_ think about the problem, now what Marx wrote. Same thing about Aristotle. __________________ Which part of "Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn" don't you understand? Last edited by HansMustermann; 7th March 2019 at 08:51 AM.
 8th March 2019, 05:52 AM #64 Darat Lackey Administrator     Join Date: Aug 2001 Location: South East, UK Posts: 86,779 Does anyone know what this thread is really about? Aristotle was wrong and that is terrible because.... __________________ I wish I knew how to quit you
 8th March 2019, 06:03 AM #65 Crossbow Seeking Honesty and Sanity     Join Date: Oct 2001 Location: Charleston, WV Posts: 12,711 Originally Posted by Darat Does anyone know what this thread is really about? Aristotle was wrong and that is terrible because.... I have been trying to figure that out myself. As near as I can tell, for some reason 'Robin' has a great deal of respect for the ideas that Aristotle had on falling bodies. However, 'Robin' is not well versed in just what Aristotle had to say about falling bodies and 'Robin' is not interested that the ideas that Aristotle had about falling bodies were thoroughly disproved centuries ago. Anyway, European scholars in the medieval period had a great deal of respect for Aristotle as well and he was often referred to as the Philosopher back in those days. So perhaps, 'Robin' has a hankering for those days. __________________ On 22 JUL 2016, Candidate Donald Trump in his acceptance speech: "There can be no prosperity without law and order." On 05 FEB 2019, President Donald Trump said in his Sate of the Union Address: "If there is going to be peace and legislation, there cannot be war and investigation." On 15 FEB 2019 'BobTheCoward' said: "I constantly assert I am a fool." A man's best friend is his dogma.
 12th March 2019, 05:29 PM #66 Roger Ramjets Illuminator     Join Date: Jun 2008 Posts: 4,100 Originally Posted by Robin Or the shorter version - yes, he would have been correct. The metal spear would have fallen quicker, just as he says. I can't see anywhere that Aristotle says that if X is A times heavier than Y then X will fall A times faster than Y. Perhaps I have missed it. He says the heavier object will fall faster. And it will. That's right. So long as the 'heavier' object falls even the slightest bit faster, Aristotle was right! Which means that this translation is wrong, right? Quote: We see that bodies which have a greater impulse either of weight or of lightness, if they area like in other respects, move faster over an equal space, and in the ratio which their magnitudes bear to each other. Therefore, they will also move through the void with this ratio of speed. But even if Aristotle's 'ratio' is somewhat less than one it still doesn't mean that speed will be directly proportional to weight. Why not? Because the 'impulse' or driving force is directly proportional to weight, but aerodynamic drag is proportional to speed squared. So the faster an object falls the smaller the 'ratio' becomes - not very useful. Originally Posted by Crossbow if one were to drop a sheet of paper and a crumpled up piece of paper, then the crumpled sheet would land before the intact sheet. Depends on how you drop them. If you drop the 'intact' sheet exactly vertical it will land first due to lower drag. But if you fold it into a dart (to get a forward center of gravity) it can glide for much longer - even though it still has less drag than the crumpled up paper. A theory which merely says a heavier object falls faster in the same medium - but doesn't specify the ratio or quantify aerodynamic effects - is useless. But I have a perfect theory that proves Aristotle was right. You see, there is an inherent proportionality between weight and falling speed - even in a vaccuum - it's just really really small. __________________ We don't want good, sound arguments. We want arguments that sound good.
 14th March 2019, 08:46 PM #67 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by Roger Ramjets That's right. So long as the 'heavier' object falls even the slightest bit faster, Aristotle was right! Bottom line is that Aristotle said that for two objects falling or sinking through a medium the heavier will fall faster than the lighter one because it will have a greater ability to divide the medium. Given that Aristotle specifies that the shape of the object is also a factor then, yes, he is more or less correct. I don't see where he says that this ability to divide the medium, even an easily dividable medium like air - will be considerably greater in every case. Perhaps you can point that out. Quote: Which means that this translation is wrong, right? As I have already pointed out, the word Aristotle uses is 'logon', which can be translated as ratio but can also be translated as proportion, correspondence, relation etc. I suppose you can assume that Aristotle really thought that if you have something that is is 100 times lighter than something else then it would fall 100 times more slowly, even though he hasn't actually said this unless you translate one particular sentence uncharitably ... And, as I have pointed out before, the discussion in that part is not even about falling objects. I quoted the part where he explicitly discusses falling/sinking objects. Quote: But even if Aristotle's 'ratio' is somewhat less than one it still doesn't mean that speed will be directly proportional to weight. Why not? Because the 'impulse' or driving force is directly proportional to weight, but aerodynamic drag is proportional to speed squared. So the faster an object falls the smaller the 'ratio' becomes - not very useful. So it is a grave fault of Aristotle's that, 2,000 years before Newton and not having any accurate way of measuring time he did not get this exactly right, ie that he did not achieve in one lifetime what it took humankind another 2,000 years to achieve? Quote: Depends on how you drop them. If you drop the 'intact' sheet exactly vertical it will land first due to lower drag. But if you fold it into a dart (to get a forward center of gravity) it can glide for much longer - even though it still has less drag than the crumpled up paper. Again, Aristotle says that the shape of the object is one of the factors that will contribute to the speed that it will fall/sink together with the weight it has to divide the medium and the resistance of the medium. He points out that some shapes won't even sink at all so clearly he is not suggesting any simple ratio. Quote: A theory which merely says a heavier object falls faster in the same medium - but doesn't specify the ratio or quantify aerodynamic effects - is useless. Writing 2,600 years ago with no accurate method of measuring small time periods and with pre-Euclidean mathematical methods. Right. What a dummy he was. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 14th March 2019, 08:47 PM #68 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 I see this attitude a lot, that Aristotle must have been pretty stupid not to have achieved in one lifetime what it took the rest of humanity 2,000 years to 2,500 years to achieve. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 14th March 2019, 08:48 PM #69 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by Darat Does anyone know what this thread is really about? Aristotle was wrong and that is terrible because.... Maybe try reading the OP, and perhaps perusing the Rovelli paper I linked. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 14th March 2019, 08:54 PM #70 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by HansMustermann I disagree with this simple issue: it's YOUR equation, not what Aristotle actually wrote. I was responding to someone who linked a paper in which he proposes a formula which he says reflects Aristotle's ideas. I point out that this equation actually conflicts with what Aristotle wrote and suggest a change which more accurately reflects what Aristotle said and I gave reasons which relate directly to Aristotle's actual words. All the rest of you have been proposing highly creative mathematical interpretations of what Aristotle said but apparently that is not a problem... __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 14th March 2019, 08:58 PM #71 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by Crossbow I have been trying to figure that out myself. As near as I can tell, for some reason 'Robin' has a great deal of respect for the ideas that Aristotle had on falling bodies. However, 'Robin' is not well versed in just what Aristotle had to say about falling bodies ... Actually I am more familiar with what Aristotle had to say about falling bodies than anyone here but I guess you have to pretend otherwise, so knock yourself out. What puzzles me is you eccentric affectation of putting quotes around my name. Are you feeling OK? __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 14th March 2019, 09:06 PM #72 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by Crossbow Aristotle did not properly account for the effects of air resistance on falling bodies. I am not sure that even today we have 'properly' accounted for the effects of air resistance on falling bodies of any shape. What should he have added to 'properly' account for this? Quote: Again, I still fail to see what has you so terribly confused. Aristotle says that given X, Y will happen. You agree that given X, Y will happen. You claim that Aristotle was wrong to claim that given X, Y will happen. And you say I am confused ... __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 14th March 2019, 09:10 PM #73 Robin Philosopher   Join Date: Apr 2004 Posts: 9,927 Originally Posted by Darat Does anyone know what this thread is really about? Aristotle was wrong and that is terrible because.... The point is that Aristotle is popularly supposed to be wrong on this subject. But if you read what he actually said then in this particular case he wasn't wrong. I remember having a similar debate about 15 years ago where I said that no educated person in the medieval and early renaissance would have believed that the Earth was flat. I got pretty much the same reaction. __________________ The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"
 15th March 2019, 04:41 AM #74 Crossbow Seeking Honesty and Sanity     Join Date: Oct 2001 Location: Charleston, WV Posts: 12,711 Originally Posted by Robin Actually I am more familiar with what Aristotle had to say about falling bodies than anyone here but I guess you have to pretend otherwise, so knock yourself out. What puzzles me is you eccentric affectation of putting quotes around my name. Are you feeling OK? If you are such a serious scholar, then a simple examination of several of my other postings would easily show you that I do use the single quote marks around just about every Username here at the Forum. Therefore, there is no point in you taking offense since I am not offending you. Also, I have been engaging in this practice of using single quotes around the Username for several years now. As for myself, since these are Usernames as opposed to real names, then I feel that using the single quotes is quite appropriate. However, if I am informed that the Username and the real name is the same name, then I will drop the use of the singe quotation mark. Note: if you still have doubts about what I have to say about this issue, then I suggest that you confer with those dead people that you communicate with because I am sure that they will give you the answer that you desire. __________________ On 22 JUL 2016, Candidate Donald Trump in his acceptance speech: "There can be no prosperity without law and order." On 05 FEB 2019, President Donald Trump said in his Sate of the Union Address: "If there is going to be peace and legislation, there cannot be war and investigation." On 15 FEB 2019 'BobTheCoward' said: "I constantly assert I am a fool." A man's best friend is his dogma.

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