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Flaw in human understanding

  1. Nov 1, 2004 #1


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    Ever since the ancient times we have noticed that the universe works in a certain way and we try to interpret it. In doing so we create models which are based upon our the physcial world (and to some extent, even if very little, culture and religion).
    But the problem lies with the fact that because the universe works in only one way, it is impossible for us to arrive at a satisfactory model of how the world works based upon our existing knowledge of the physical world, which is incomplete.
    There for instead of trying to create models (like the string theory) we must place more emphasis on the mathematical equations rather than the theories.

    For example, if any other intelligent life form exists they need not neccesarily follow the same model (like the atomic model) and they might not know about electrons or protons.

    Therefore isn't our approach to understanding the universe in terms of models rather than equations fundamentally flawed?
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  3. Nov 1, 2004 #2


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    I don't understand what you see as a "flaw". No, our understanding is not perfect and other intelligent life, with other imperfections might arrive at a different understanding. Is that bad? That seems to me to mean that if we were to meet with such a species, both species could learn much more from each other than if their theories were exactly the same.

    Our understanding of the universe not perfect because we are not capable of perfection. Where's the flaw in doing the best we can?
  4. Nov 1, 2004 #3


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    You are correct. I was trying to point out the fact that it is impossible for us to build a physical model on how the universe works. Therefore working in that direction is not as efficient as trying to explain the laws of physics in equations.
  5. Nov 1, 2004 #4


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    Apparently you and I have completely different ideas as to what a "model" is. An equation IS a model.
  6. Nov 1, 2004 #5


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    I think siddharth is arguing the case against trying to derive metaphysical meaning from the equations we do create. A classic example here would be varying metaphysical or ontological interpretations of quantum mechanics (many worlds, 'observor' driven collapse of the wave function, etc.) vis a vis the metaphysically conservative logical positivism of the Copenhagen interpretation.

    Even if we grant siddarth the point that we'll never get the ontological picture of the universe quite right, there is still something to be said for conducting such activity. One very practical outcome of trying to interpret the scientific data and formalisms in a stronger ontological sense than is strictly 'necessary' is that creating such 'ontological' models may spark ideas for new principles, new predictions, and new experiments, which in turn may wind up assisting in the progression of the more practical, nitty gritty side of things.

    For instance (someone please correct me if I'm mistaken), the many worlds interpretation of QM is the driving motivation behind the development of the quantum computer, which would be a very practical application of what might otherwise be regarded as a rather airy or insubstantial idea. And the emprical results of the quantum computing movement would in turn inform our ontological models of QM, which could lead to further practical developments, and so on.
  7. Nov 3, 2004 #6
    Very interesting topic!

    I would even go further and say that our knowledge of the physical world is not incomplete, but simply non-existent. It seems to me we know absolutely nothing about the objective world. Absolutely nothing.

    Think of it this way: at some point back in history we, or whatever creature came before us, knew nothing. We can't seriously postulate that biological organisms were created with any knowledge about reality. Everything we have learned, as individual and as a species, is the result of our interaction with the world around us, or the knowledge of past interactions which has been given to us through education or genetics.

    But here is the million-dollar question: if you know absolutely nothing about reality, how would you learn anything at all? You see, it's a trivial thing to learn one fact when you already know a bunch of facts, but how exactly do you learn one fact when you know absolutely no other fact? How did the first piece of knowledge about reality came about?

    My guess is this: it never happened! We are as ignorant of reality as the first being ever created. So how do we explain the perception that we do know a lot? I think you have touched on the issue.

    Would you agree with me that the only knowledge we can possibly have is the knowledge of self-consistent, abstract structures?

    Self-consistent abstract structures are always true regardless of their meaning. At a minimum we can, at least in principle, know all propositions that are true in any reality. For instance, tautologies are always true, so any statement about reality that is tautological is a true statement - regardless of what it means! By discovering what is true in any reality, we discover what is true in our reality. I strongly believe that is what physics is about.

    Yet if both their model of reality as well as ours are consistent, it's perfectly possible to translate any of their concepts into our concepts. So electrons and protons do exist for any observer insofar as the mathematical descriptions of 'electron' and 'proton' is devoid of inconsistencies.

    I wouldn't say it's "fundamentally flawed" because what you described is, in essence, what we are doing. Since a self-consistent structure can't be proved wrong by any experiment, experimenting with reality is just an easy way to check the consistency of a theory. In the end all physicists deal with is mathematical concepts; only they like often tend to think otherwise. That attitude could perhaps be called a flaw, but the process is the best available given the limitations of reason.

    I hope this makes some sense.

    (as an afterthought, although I said we know nothing about reality, I also said we know what is true in our reality which is also true in any reality. This may sound contradictory, but what I really mean is that we can't possibly know why the world is the way it is given that it could be different; all we can know are things about our world which must be that way out of logical necessity)
  8. Nov 4, 2004 #7

    Unfortunately Gödel proved that we can not ever prove from within a mathematical framework that this framework is 100% sure correct.

    So, even building mathematical models and sticking to them is not of any guarantee.

    Besides, the very start of building a mathematical model is based on some assumptions of reality.

    The question you touch in my oppinion is related to the question: does science makes sense. The answer, although one can get very phylosofical about it, boils down to the choice between a structurally sound or "rational" approach, a purely speculative approach, or the choice for no approach at all.

    I think people visiting this forum generally choose for the structurally sound approach.


  9. Nov 4, 2004 #8
    I'm not so convinced that Godel proved anything of much relevance to this discussion. Somehow physics didn't collapse after he came up with his proof. I think Godel's theorem is too complicated and too new for most people to understand what its consequences are. It may turn out to be something quite mundane which has been known for ages, only expressed in a convoluted way (this is my interpretation of it anyway)

    Well, the fact still remains that a self-consistent model can't be falsified by any observation, therefore all mathematically correct assertions are true statements about reality. The real problem is to give meaning to those mathematical assertions: "does this equation apply to that phenomenon?" kind of thing. This is where I think is the flaw in scientific thinking: any answer to such kinds of questions, any attempt to give meaning to abstract ideas, is doomed to be proven wrong sooner or later. That means any interpretation of mathematics as pertaining to real phenomena is essentially false; it's just a matter of time before someone finds out.

    It goes beyond that. For one thing, "reality" itself is an abstract concept, so our models of reality are abstract models of an abstract concept. As such, all we have to do is make sure the abstract concepts in our model are consistent with the abstract concept of reality, which is part of the model itself. Which is why mathematics, not observation or experiment, is the best tool to learn about reality.

    Well, first of all this is a philosophy forum so I think we should get very philosophical about it. That's what I'm here for anyway, otherwise I'd be posting on the science forums. So, getting philosophical about it, my perspective is that science does make sense only insofar as scientists admit it is not a true description of reality. If a physicist says "we have determined that this phenomenon can be described/predicted/understood using this theory", then it makes a lot of sense and no one will dispute it. But when scientists come and say that one phenomenon is the only possible consequence, or the only possible cause, of another phenomenon, then everyone knows they are making a claim to know what cannot possibly be known. When scientists act like that, science stops making sense.
  10. Nov 4, 2004 #9


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    What do you count as 'knowledge of reality'? Or more generally, what counts as 'knowledge'? Can it be purely computational in nature? Must it be mental? If so, must it be an object of experiential consciousness? Does sensory experience count?

    So you believe that physical laws are tautological, or necessary? On what grounds? Given what we know, it seems they just as well could be contingent, i.e. possibly different in different universes. And if they are contingent, then by your claim we shouldn't be able to know anything about them.
  11. Nov 4, 2004 #10
    Lots of good questions; I will address them in a different order:

    What counts as 'knowledge': your perception that this question must be answered is actually part of the problem. We cannot know what 'knowledge' is. We have to acquire knowledge about things without knowing what knowledge is, yet we have been quite successful at that. That is only possible because the answer to the question "what is knowledge" is irrelevant.

    Can it be purely computational in nature?: it follows from the above that this question is also unanswerable and irrelevant.

    Must it be mental?: OK, now we start the process of lifting ourselves by pulling our shoelaces. Is knowledge mental? If we say it is, we imply that wherever you find knowledge you will also find a mind. If we say it isn't, then we imply it's possible for knowledge to exist completely by itself, with no relation to anything else - sort of "floating in nothingness", if that gives you the picture. Now exactly what is the difference between the two scenarios? The fact is, we can say "knowledge is mental", or we can say "knowledge is not mental", it doesn't matter. What matters is, if we say "knowledge is mental", then we cannot accept as true any assertion that implies that knowledge is non-mental. And vice-versa.

    If so, must it be an object of experiential consciousness?: same scenario as before. Taking "knowledge is mental" as a premise leaves open the possibility of it being an object of experience, or not. As you duly noted. Again, it's your choice. Only be careful; as you make more choices, maintaining consistency between them becomes increasingly difficult.

    Does sensory experience count [as knowledge]:? again, a matter of choice.

    The challenge is not to find the answers to those questions, for they are nowhere to be found. The challenge is to make up answers that do not contradict each other. I can now answer your first question:

    What do you count as 'knowledge of reality'?: nothing.

    Now I need to explain what I just said in light of everything I said until that point. I'm trying to build a self-consistent abstract model of everything I know about everything. I take it as a premise that "reality cannot be known", and try to make all my knowledge consistent with that premise. You may choose differently; you may take "reality can be known" as a premise, but my experience tells me the task of keeping all your knowledge consistent with that premise to be incredibly difficult, perhaps impossible. To start with, given that in your model your conscious mind is separated from everything else in existence, you will have a heck of a hard time understanding how you can know anything at all about anything that exists (other than your conscious mind). That is actually called "the problem of solipsism", and last time I checked it had not been solved.

    I don't believe in physical laws! From my perspective, the perception that the universe is ruled by laws is an illusion. Not a sensory illusion, just a cognitive one, like the ancient Egyptians who perceived the world as being ruled by the movement of celestial bodies.

    How that illusion comes about is actually a very simple process. We come up with "physical laws" which supposedly allow us to predict the behavior of matter, but anyone knows that the behavior of matter is, far more often than not, extremely unpredictable. So how do we reconcile our belief in those physical laws with our inability to apply them except in extremely restricted scenarios? Simple: we come up with more "physical laws" which explain why our predictions fail. "It's there but we cannot see/measure it" kind of thing.

    Again, that seems like a valid position but it's a very hard one to sustain on an intellectual level.

    It seems that way, but it isn't. You think it's possible for a universe to exist without quantum mechanics or relativity, but if you examine it more closely, you'll realize the notion is erroneous. Our science is not a description of our universe, it's a description of our point of view. The laws of physics are statements about our way of thinking about the abstract concept called "universe", not about whatever it is the concept refers to. So for as long as you remain rational, you will perceive any universe the same way: as a collection of objects moving through space and time. And when you stop being rational, then even the concept "universe" ceases to exist for you.

    Well, I think the particular features of our universe are contingent, in the sense that I can think of a universe without stars, planets, organic matter, and so on. But the particular features of our universe are not contingent on logic or anything derived from it (ie, science). For as long as a universe has space, time, and matter, it can be described with current physics. And if it doesn't have space, time, or matter, then it's not a universe to begin with.
  12. Nov 4, 2004 #11
    Nobody doubted that it was possible for a universe to exist without quantum mechanics or relativity before experimental evidence for these theories was discovered. Even then, many people refused to accept them. Even today many people refuse to accept them, and live and die that way quite happily. How does this make them a description of our point of view? They exist purely because they describe the way the universe works. It would be a very foolish point of view to take otherwise. It is not the sort of thing you would make up.
    Last edited: Nov 4, 2004
  13. Nov 4, 2004 #12
    Have you ever studied QM? I'm not sure if it is what you have in mind.
  14. Nov 4, 2004 #13
    I don't think you understand what I'm talking about. Forget quantum mechanics or relativity. Can you think of a universe where 1+1=3? Can you think of a universe where you get one stone, then another stone, and somehow end up with three stones simply by putting them side by side?

    Well, the thing is, in one way that universe can't possibly exist, but in another way even our universe is like that. There are many cases when we put one thing beside another and we don't end up with two things; it's very common in our own world to end up with 1.1 thing, or no-thing, when we put one thing beside another. But when that happens we don't proclaim mathematics is wrong, we simply find a different equation to describe what we observe.

    It's because of the way we adapt our thinking to what we observe that I said no universe can exist without quantum mechanics or relativity. Surely in a universe where nothing moves relativity is not relevant, but a static universe can't prove relativity wrong, and a universe where things move can always be described using the equations of relativity.

    That is completely beside the point. There is science, and there is the politics of science - who is on what side. The politics of science are irrelevant to a philosophical discussion on its fundamentals.
  15. Nov 5, 2004 #14
    What I wanted to point out was the following: not only are we not 100% sure that the mathematical model represents a reality, we can not even be sure about the mathematics itself.

    Thus pointing out that if you really want to doubt the appropriateness of using mathematics to build a consistent view on the world, you should doubt mathematics itself (this is where Gödel comes in), hence you can question anything.

    This showes that if you start having serious doubts about the scientific approach, you can very well show that you should be consistend and doubt anything. This leaves only pure speculation or utter passivity as other possibilities to approach reality.

    Hope this clears up the fog a little.
  16. Nov 5, 2004 #15
    That is as far from what I said as it could possibly be. I do not question mathematics, quite the contrary. Whatever its shortcomings might be, mathematics is the upper limit to human knowledge - beyond math there's nothing we can know. When you get to the point where you can measure a certain phenomenon and accurately describe it through mathematical equations, there's nothing else about the phonemenon that you can know.

    I have no doubts about the scientific approach - it works like nothing else and we all know that. What I'm talking about is the essence of reality, the true nature of things beyond their appearances. Not only I doubt that world can be described with mathematical equations, I doubt it can be described at all.
  17. Nov 5, 2004 #16
    I don't agree with this at all, because experimentation always teaches you a lot more than isolated maths. I don't think you are taking into account what experience can teach you. We could phrase this issue as "Can a virgin model sex using equations and know everything there is to know about it?".

    I give up.
  18. Nov 5, 2004 #17
    You are confusing knowledge with experience. Knowledge of a thing is not the thing. Knowledge of sex doesn't have much to with sex. A person can be extremely knowledgeable about sex without ever experiencing it. A person can be completely ignorant about sex even after a lifetime doing it.

    To say someone "learns" about sex by losing their virginity is, in my opinion, trivializing the experience. Experience is profound and full of meaning; knowledge is for the most part an irrelevant pastime of bored people, Like us who post here.

    (I just thought of a cute signature for my posts: "I'd rather be having sex" :smile:)
  19. Nov 9, 2004 #18
    I feel that you are confusing knowledge with calculation. I have the knowledge of what a clarinet sounds like. This knowledge can only be gained through direct experience, not through computation or reasoning.

    On the whole you seem to be agreeing with Kant, who said that we cannot know the 'noumenal', things as they are in themselves, and that our knowledge can only be of our own human concepts, not of 'transcendent' reality, reality as it really is. In other words, our knowledge and conceptualisations of the phenomenal world are 'theory-laden' and thus uncertain.

    However you (and maybe Kant) missed the fact that we can know the noumenal, and the transcendent, if consciousness underlies reality and if we can have direct experience of that underlying reality. It's a big if, but it does not matter whether this is the case or not, in principle at least it offers us the hope that there is a way of overcoming Kant's limits to knowledge. It also offers us a way around Goedel's limits to proof, since we can know things directly rather than by deriving theorems from axioms. (Just as we can decide Goedel sentences from the meta-system).

    I don't believe you said that.

    Completely ignorant? Even if you've only done it once you can't be copmpletely ignorant about it.

    So when one loses ones virginity one does not learn anything about sex? I think you'll find out that this is not the case. :biggrin:

    Again I feel you confuse knowledge with theorising, calculating, computing, reasoning etc. Experience is exactly and precisely what brings knowledge. Knowledge is not restricted to knowledge of mathematics, philosophy, science and so on. I know what it is like to be me, and I don't have to theorise at all.

    Still, I agree with you that a mathematical model of reality can never be more than theoretical and thus represents uncertain knowledge of it. The incompleteness theorem tells us something very important about knowledge, and I feel that you're very wrong to dismiss it as having no metaphysical implications. Goedel wouldn't have agreed with you. Nor would Stephen Hawkings, whose essay 'The End of Physics', which briefly explores the consequences of the incompleteness theorem for physics, is online somewhere.
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