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  1. Apr 16, 2004 #1
    Do all things occur according to logic? If so, then there is freewill. Or is freewill an illusion? How is this to be determined?
  2. jcsd
  3. Apr 16, 2004 #2
    Cause we don't always know what the causes that initiated the event's history, in their totallity, so separating it out, isn't easy...generally speaking, the Universe, and material, or the physical world, do follow 'cause and effect' rules, seemingly without failure, other then perhaps our oversight of just what was the 'cause and effect' history....that can be deteminately long in Physics, as the history of the Universe itself.....
  4. Apr 16, 2004 #3
    Have you heard of Nikola Tesla's teleautomatic theory?
  5. Apr 17, 2004 #4
  6. Apr 17, 2004 #5
    Nikola Tesla found that every reaction has a cause and effect. Everything we do is because something caused us to want to do it. He pointed out that a ball and only one ball in a finite space, is at rest unless something acts on it, say another ball. That is the apparent case with living things. of course, for us it a much more complex series of cause and effect. For example, I am a memeber of pfs because I enjoy discussing philosophy and physics because something in my past caused me to etc.

    do you understand my summary?
  7. Apr 17, 2004 #6
    Yes, but I would distinguish between 'thoughts' and the physical reality with respect to cause and effect.....

    To many of those Worlds stupidist robbers on that television program to believe that it occurs with the same rigidity, in thought, as in physical reality, cause in thought every one of those people believed that they would get away with what they did...or tried to do, in thought they had had it completely planned out, and it worked!....well, in thought.......

    do you see my point?
  8. Apr 18, 2004 #7
    yes, I see your point.

    But, because they were not conscious of the apperent flaw in their plans, they were deemed one of the stupidest robbers in the world. Cause and effect doesn't neccesarily mean we are conscious of the cause and effect; they are intrinsic properties. Thoughts can effect our physical reality, but not always the way we want them to.
  9. Apr 19, 2004 #8
    Well, it was a little bit more towards the 'Free Will' part, just because you "Willingly Choose" something, doesn't mean that cause and effect will get it for you, or that your thoughts, following the cause and effect, will result, as such....

    But I would agree thoughts can affect physical reality, just that that one is really difficult to prove.....to say the least....
  10. Apr 19, 2004 #9
    Thoughts can effect our physical reality in a simple way. A thought can provoke my hand to reach for the salt. That is not very hard to proove.
  11. Apr 19, 2004 #10
    I say that freewill is an illusion. Sure, our thoughts decide our actions, but our thoughts are themselves results in mathematical causality.

    However, we can never know what it is that we will think, only that it is inevitable. This has led me to make decisions as if I am the only person with free will, even though I am as lacking as the next guy or girl.
  12. Apr 20, 2004 #11
    Hume said that our concept of causation is a matter of inference, not of deductive logic. We say that the moving ball which strikes the inertial ball causes the inertial ball to move because it regularly does so. But we do not see the actual cause. We just see one event follow another.

    Consider the somewhat trivial, but pointed, example of two balls colliding on a table. You may say that one causes the other two move. But, unbeknownest to you, I am pressing a lever under the table just as the two balls come into immediate proximity so that the second ball begins to move.

    Of course, the point here is that in every case we can conceive there being an unknown mechanism which also influences the way things behave. We don't see the causation. We just experience the regularity of the way things behave. Important distinction.

    Also, I think it is a confusion to say that "things occur according to logic". Logic is not a natural law, it is a model of reasoning. There may be natural laws which dictate how things occur, but this is not logic. Logic may be able to model these natural laws, but it is not identical to these natural laws.

    As far as determinism is concerned: Consider Aristotle's classic example of "Either there is going to be a sea battle tomorrow, or there isn't going to be a sea battle tomorrow." Seems pretty straightforward. After all, P or not-P is a tautology. Determinism says that there is only one possibility, only one future. So whether there is or isn't going to be a sea battle tomorrow has already been determined. Whatever happens tomorrow necessarily happens.

    Consider this: The captain on one of the ships has a super-duper-quantum-indeterminacy computer. He pushes a button and the computer gives a completely random choice of 0 or 1. If the answer is 0, the captain remains on his present course. If the answer is 1, the captain changes direction. Let's suppose that if the captain remains on present course there will be a sea battle tomorrow. Now, because the computer is perfectly random, can we really say that whatever happens tomorrow necessarily happens? It seems that perhaps the best we can say is that there is a finite set of possibilities for what occurs in the future.

    You might want to read about modal logic, which involves the notions of necessity and possibility. The relevant part here are the interpretations of modal logic. Is every possible situation a real existant thing? Or is the only occuring situation of those possible situations a real existant thing?
  13. Apr 20, 2004 #12
    Who's Hume?
    Yes, we only see the effect of the force. This applies to all things we observe and study. We can make equations of force vectors and the sort to deduce the presence of a force. Causation can be a matter of inference and deductive logic. We could create a situation where a ball does hit another ball mathematically. that is deductive logic.
    Also, we don't need to see the cause; the cause may be deduced from the fact that there is an effect.

    Whether or not we see the causation, we instinctively realize that there is something causing it to move. The is a very simple logical deduction. It can also be called an inference, because the observer (from past experience) would have noted a pattern, where when a force is applied to an object, it moves in the direction of the force. And the observer may deduce, from his accumelation of examples from past experience, that there is indeed such a pattern (as was aforementioned).

    ah, but logic was an infered conception. The idea of logic must have been concieved from an observer who infered a certain pattern of behaviour. A ball will move in the direction of the force that was applied. This is a logical law which specifies the basic, natural order (of course, in the example, "ball" is a variable) of motion.
    Natural law is superimposed with logic; there will be a reaction when such and such make some sort of contact in a variable method.

    Whatever happens tomorrow [to us individually] is random then? There is no cause and effect sequence in our brains that induce us to feel a certain way so that we do or say something which then causes to do someting else...? But, of course, such cause and effect sequences in the brain would occur at a microscopic level, which would indicate the prominent presence of quantum effects, which would make the whole ordeal even more random, for the observer calculating the approximate cause/effect sequences.
    Even then, if you recall Albert Einstein's argument against Heisengberg's Undeterminancy Principle, Einstein points out that though we will never know the exact position and velocity of a particle at a given time simoltaneously, (but only one or the other) there will always be a definite answer that would be impossible for us to know. After all, the reason why an electron gets excited as we increase resolution on it is because we are shooting more photons at a higher frequency. If we could view the electron without doing bombarding it with anything, would we in fact defy the undeterminancy principle and know both the position and velocity at a given time simoltaneously?

    I will read on those topics. they seem very interesting.
    In answer to your final question, only what is naturally possible in this universe can happen.
  14. Apr 20, 2004 #13


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    when i see the word determination, i think of human or animal will. something drives us to desire certain things (not limited to our instinct of food, sex, sleep, etc). some of us are determined to win, some of us are determined to express creativity and so forth. why do we have these desires? is the need to be creative hardwired into our biology? why are some determined to be their best, but others are content sitting on the couch? when i think of these questions, i wonder how there can be any sort of rhyme and reason to how humans think and behave, thus leading me to believe we ultimately do have free will, just many of us don't know how to use it.
  15. Apr 21, 2004 #14
    Scottish philosopher of the 18th century.

    This is true, but you are talking mathematics, not empirical science. Empirical science is a matter of inductive inference not of deductive logic.

    The exact cause may be only inductively inferred. We can never be certain, beyond any doubt at all, that what we believe to be the cause actually is the cause.

    The claim that an effect must necessarily have a cause is very contentious. In fact, many things occur not because they have been caused, but because of some statistical inhomogeneity.

    Again, the claim that there must necessarily be a cause is contentious.

    If an observer concludes there to be a pattern based on a significant accumulation of examples from past experience, then he is making an inductive inference, not a deductive inference. For instance, it is reasonable to claim that there is a chance that an example will occur which does not conform to the pattern. This is one of the important lessons of Husserl's phenomenology (early 20th century philosopher).

    Logic is a model of reasoning, not of natural science.
  16. Apr 21, 2004 #15
    That reminds me that it appears that at any given point in history people generally believe that all causes and effects have been explored and explained, but much more likely is that these are the most obvious explanations like this ball hits that one and causes it to move, there may always be something more to things than anyone knows.
  17. Apr 21, 2004 #16
    Would do you do the honors of describing just what the difference is between inductive logic and deductive logic?
  18. Apr 22, 2004 #17
    Well, one difference I'm making the point of using in this discussion is that a conclusion reached by an inductive argument is always, in principle, falsifiable. On the other hand, a sound conclusion reached by a deductive argument is never false.

    The problem for science is that it assumes that a certain "natural law" is valid for infinitely many instances. However, it has only finitely many instances to use for evidence that the law is true.

    A bit more technically, for a valid deductive argument, if its premises are true, then it's conclusion must necessarily be true. On the other hand, for a cogent inductive argument, if its premises are true then its conclusion is probably - but not necessarily - true.
    Last edited: Apr 22, 2004
  19. Apr 22, 2004 #18


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    A bit more technically, for a valid deductive argument, if its premises are true, then it's conclusion must necessarily be true. On the other hand, for a cogent inductive argument, if its premises are true then its conclusion is probably - but not necessarily - true.

    But how do you show the premises are true? Either you have to have a transcendent source for them, like Kant's a priori, or else an infinite regress.

    And I don't see the force of your "infinite cases" argument in the case of science. You can have a function with an uncountable number of cases (arguments and values), but completely determined by a finite set of parameters. Say a circle, determined by three points.
  20. Apr 22, 2004 #19


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    The thing with the quantum computer example is exactly what particle said, that the event is not truly random. The computer spits out 1's and 0's according to laws of cause and effect, we just can't observe the cause or the effect. The result is only random in that we can't predict it. Perhaps an example as to what I'm talking about now.

    Let's say you blindfold and disorient yourself, then swing a bat, hoping to hit a pinata that is in your vicinity. You have no way of knowing whether or not you will, and so the event is random in the sense that you can't predict the outcome, but it is not truly random in that you could predict the outcome if only you could see what was happening. In the same way, if we could see quantum interactions without disturbing them, we would be able to predict the actions of the quantum computer.

    The same thing goes with thought, if thought is entirely a phenomenon of the brain, which is a topic being discussed in a ton of threads right now. If thought if entirely an emergent property of many neurochemical interactions taking place at the same time, then simply knowing the positions and velocities of all the pertinent molecules would allow us to predict thought, and thus conscious action. Of course, no one will claim to begin with that unconscious, or reflexive, action is free, so by being able to predict the outcome of conscious action, we will have effectively done away with free will. Of course, given that the human brain is not a closed system, the molecular interactions taking place within it are affected by sensory perception, which is in turn affected by molecular interactions taking place outside of the body. To accurately predict future action, you would have to know the positions and velocities of every particle in the universe as well as the expressions, in thoughts and actions, of every interaction taking place in the brain. This is obviously an impossible amount of knowledge to have, but still, it is at least theoretically possible to to predict all future actions, if thinking is entirely a physical phenomenon taking place in the brain.

    The only out for a believer of free will is dualism. Given that we have no idea how a non-physical entity would behave, and whether or not it is subject to the rules of cause and effect, postulating a non-physical origin of thought might free human action from the constraints placed on it by the nature of the physical universe.
  21. Apr 22, 2004 #20
    Instincts, thoughts, and whatever makes up the human mind will always puzzle me. I believe it will remain the last thing to ever be exposed, discovered, and explored, and I believe we will never reach the end of things before it.
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