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Everything posted by SpookyKitty

  1. Suppose you had an infinite amount of time on your hands. How exactly would you go about searching through every possible function? How would you know when you've found the best one possible? What do you imagine distinguishes it from all the rest?
  2. @Nicky and @Doug Morris Is it possible to measure the "simplicity" of a provided answer? Also, just drop this side argument about what an open-ended question is and isn't. It's just fucking stupid and not even remotely productive.
  3. Why not try every function? Can you attempt a definition of elegance?
  4. @Doug Morris I just looked up "genius" in the dictionary, and it said "see Doug Morris" Your second answers are not conceptually lazy at all. You are now on your way to finding a general solution. But why fit polynomials in particular? Is that the only class of functions you can try to fit to the given data? Suppose that 1, -1, 1, -1, 1, -1, 1, -1, ... had been one of the sequences. Any polynomial fit here would result in the terms tending towards (+/-) inf at some point, yet that doesn't seem "elegant". That being said, is any class of functions equally as good a space to search through as any other? Why might one or the other be better? Also, how would you define "elegance"? @Nicky "Open-ended" means that I will never give you the correct answer although there is one. And just because a problem is "open-ended" does not mean that some answers are not better than others. That being said, at least you tried, but I'm not at all convinced that you gave the problem 100% effort.
  5. Use the full power of your rational mind to answer, as best as possible, the following open-ended problems: 1) Predict the next five numbers in each sequence and justify your reasoning: a) 0,1,2,3,4,5,6,7,8,9,10,11,.... b) 0,1,3,7,15,31,63,127,... c) 0,1,-1,3,-5,11,-21,... d) 0,0,1,2,1,-2,-3,2,9,6,-11,... e) 0,0,1/3,1/3,2/15,7/90,73/630,... 2) Do the same as above except come up with a different answer and justify your reasoning 3) Which of your two answers is better? 4) Why?
  6. This is true, but the local relation between force and acceleration has nothing to do with whether or not a theory is causal. Imagine that you have a ball sitting at rest on a table. Now imagine that a leaf falls somewhere in the Andromeda galaxy. The ball, according to Newton's theory of gravitation will begin to move at the same instant that the leaf does. Thus, we have no way of telling whether it was the leaf that caused the ball to move, or whether it was the ball moving that caused the leaf to fall. On the other hand, in relativity theory, the disturbance in the force caused by the leaf has to propagate at at most the speed of light, and so, we always have that the cause precedes its effect.
  7. Yes. This sentence is ungrammatical, and I can't guess what you're trying to say. But not being causal doesn't mean that the theory isn't a good theory. Being anti-causal, in the sense that future events can effect the past, however, would mean that it isn't a good theory. No. In physics, a cause is an event and the effect must also be an event. Accelerations and forces are not events.
  8. I don't know if we disagree, because either we're in agreement or we're talking past each other. So I'll state my point as clearly and briefly as I can, and then you tell me what you disagree with and why. A scientific model is an abstract representation of a real thing. For example, scientists talk of a model of the hydrogen atom, a model of a star, a model of the solar system, a model of a mechanical system, and so on. A scientific theory is what tells you how to build models of things. For example, the theory of quantum mechanics gives you a set of assumptions and tells you how to build quantum mechanical models of atoms from those assumptions; the theory of hydrostatics combined with the theory of nuclear fusion and the theory of gravity tell you how to build models of stars; Newton's theory of gravity tells you how to build models of the solar system, etc.
  9. No. It simply doesn't. There shouldn't be one. Yes. Definitely. In SR, forces are entirely local, and so there is no instantaneous action at a distance. So if I close my eyes, then the sun ceases to shine? Your definition of causality is absurd. By "assumptions" I mean statements which help simplify the problems in the field. No feasible scientific theory can take into account literally everything which could affect the outcome of the experiment. Furthermore, the role of these assumptions (fundamentally) is to restrict the range of possible models, so as to facilitate computation of outcomes of experiments or to make it is easier to search the space of all models quickly and/or efficiently and also to evaluate them. I think I can come up with an even simpler domain over which we can explore the concept of scientific theory. Let's say that you're investigating an unknown (possibly alien) language. You have some documents written in that language and one of them says the following: "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum." And your job is to figure out what are the possible words of this language. (Actually, I'm currently working on an AI which solves this problem). One possible theory is that the words in a language consists of a small set of syllables which can be combined to form the words in that language. (This is our first assumption). So a model that this theory produces, for example, could say that some of the syllables of this language are: lo, rem, ip, sum, do, sit, a, met,.... And so, it would allow us to predict that we can have words like "lorem" and "ipsum" which are actually in the document but also we could have words like "sumdosit" and "aremdo" which aren't. Another possible model is that the only syllables are: a,b,c,d,e,f,g,h,i,k,l,m,n,o,p,q,r,s,t,u,v,x,y,z. So this model also predicts words like "lorem" and "ipsum", but it also predicts words that the first model doesn't, for example, "tstrqpomlk" and "defghrp". Which model do you think is a better explanation of the data? An essential component of a theory is a method for evaluating its models. So for our theory we could require that good models first of all assign very high probability to the data that we actually observe. This is so that we can make very precise and correct predictions about the data. By this criterion, the first model is clearly superior to the second. On the other hand, suppose that we come up with the following third model: "lorem, ipsum, dolor, sit, amet,..." where the syllables of the language are precisely the words we observe in the document. This model assigns extremely high probability to the data (In fact, you can't possibly do better). But it seems to sort of cheat because it is overfitting the data. So we could introduce a third assumption about what makes a good model, that is, that a good model minimizes the ratio (#of characters needed to specify the syllables in the model)/(#of characters in the data). This would prevent overfitting. The algorithm that I designed uses these assumptions to produce models of arbitrary languages which are more like the highly precise and very simple first model and less like the imprecise but simple second model and also less like the extremely precise but absurdly complicated third model.
  10. No. The acceleration is produced at the exact moment that the force is applied. Not a finite amount of time afterwards. Acceleration is a measure of the instantaneous rate of change in velocity over time. This is a misrepresentation of my argument. A cause must precede its effect chronologically. Because forces produce accelerations instantaneously, one cannot cause the other.
  11. No. A cause must precede its effect. The acceleration and force are always simultaneous.
  12. If this were true, then Newtonian Physics is not a scientific theory. Newtonian dynamics is governed by the second law, which has nothing at all to do with causes and effects.
  13. A scientific theory is a collection of assumptions about some field, which, given a model of an experiment in that field, produces a prediction about the outcome of that experiment.
  14. This is stupid. Just go up to the prettiest girl and buy her a drink. Then let the losers play whatever dumb games they like.
  15. I think you've misunderstood my argument. I am not making any grand metaphysical or epistemological claims about "the greatest logical necessity there is" or some such. I am merely demonstrating that the causal structure you proposed is not a substitute for universals. There is no redundancy. Universals are not the same as concepts. And I could also ask you again, if you think universals are a redundancy, then why isn't the same true of particulars? If you have particulars in reality, then what's the point of having them in your mind? Or, if you have them in your mind, then why bother with them in reality? Seems """fairer""" to just get rid of them. Because facts can't contradict each other. No it is completely different. A universe where an apple can be both red and not-red at the same time in the same way is inconceivable. A universe where an apple barks one day and writes sonnets the next is weird, but not inconceivable. I believe that both things are impossible but for very different reasons. Hence, the causal and universal structures must themselves by very different. In any case, they are not the same. It's a special case of a universal. Just like zero is a number, even though you can't really count zero of anything.
  16. I agree that universals for contradictory properties exist (e.g., the property of being both red and not red in the same way at the same time) but that such universals can never be instantiated. That's totally different from saying that contradictions exist, as that would mean that facts can contradict each other, which is false. I would definitely say that universals for numbers exist even if there were no things to be counted or if the act of counting has never and can never be done. I would like to see your arguments to the contrary. That's a humorous way of putting it. Universals are not about categories and categorization. Nor are they about natures and causality. They are about predicates and predication. A universe without universals would be indescribable since you would not be able to predicate anything of anything else. Indeed, I would argue that such a universe wouldn't be anything at all. Since to say that a universe is a certain way is to predicate something of it, and predicates would never be justified in a universalless universe. A universe without causality, on the other hand, would merely be weird and unpredictable, but not indescribable.
  17. It isn't true that a universal which is never instantiated is unknowable. Some universals can be grasped without ever witnessing their particulars. Knowledge of their existence can be inferred from knowledge of other universals. For example, I have never seen (and will probably never see) a collection of 10^10^10^10^10 things. Nonetheless, I know that the universal corresponding to that number must exist because its existence can be inferred from the laws of arithmetic. When a universal becomes instantiated, it itself does not change in any way. It is the particular(s) embodying the universal that change(s). What causes particulars to change are causal forces exerted by other particulars. Hence, it would be far more sensible to say that particulars cause other particulars to instantiate universals.
  18. Yes, I would say that universals exist even if they are not instantiated.
  19. I believe that universals do not have causal powers or spatial location. I don't know if the set of universals is identical to the set of things which don't have cause powers or spatial location.
  20. A seed is a potential tree, and once it becomes an actual tree, it is no longer a potential tree. A universal which was not instantiated but then later becomes instantiated does not cease to be a universal. Therefore, a universal cannot be a potential particular.
  21. I would agree that knowing means that there is a mental entity that corresponds to what is out there, but not that there is a mental entity which is literally identical to what is out there. My mind contains representations of apples, but not literal apples.
  22. I don't know what led you to believe that I believe that, but no.
  23. Universals exist "out there" and they are decidedly not mental entities. If your question is how can we use our senses to detect the existence of universals, then your question is how can we use our senses to detect the existence of things which are not sensible. The question of the existence of universals is a philosophical one, not a scientific one. Observation cannot decide it one way or the other. The only way to know about them is to use reason.
  24. Aristotle was the first to deal with this problem. He pointed out that ancient Greek (and also modern English) do not distinguish between the "is" of predication and the "is" of identity. When this distinction is made, the sentence "The apple is red" is understood as red(apple), while the sentence "the apple is California" becomes identity(apple, California). When understood properly, every predication expresses a universal. Supposing that it is true that predicate clauses do not refer to any aspect of reality "out there", why can't the exact same argument be made for subject clauses? In that case, reality would consist of neither particulars nor universals. And unless you can somehow provide a coherent account of it without using either of these things, it seems we're doomed to a sort of extreme skepticism. I think you are putting the cart before the horse. It's not that universals exist because human languages have predicates, but that human languages have predicates because universals exist. This passage is, in my opinion, unrelated to the discussion. Nonetheless, this is an opportunity to put into writing what I think is wrong with it. Peikoff fails to distinguish between events and facts (specifically the fact of the occurrence of an event with the event itself). Notice that he switches from talking about what is the case to what occurs. Facts do not "occur" nor are they "caused". These are aspects of events. Furthermore, facts are not limited to being merely about events or particulars. Facts can also be about universals (that is, about properties of and relations among particulars). Here's an interesting example of this sort of fact: "The number five is prime". This sentence does not refer to anything that happens. Nor does it refer to any ordinary thing. The number five is a universal. The predicate "is prime" is a higher-order universal. Note that this fact cannot be reduced to facts about ordinary objects. If we have five apples, it would be absurd to say that it is some property of the individual apples that makes their number prime.
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