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How did the Brain Come into Existence?

  1. Oct 25, 2004 #1
    So just how did the brain come into existence physically? ... To exploit an available resource perhaps? :wink: Which, I think is the whole point, why does anything evolve, if not to exploit the resources at hand? Why did our eyes elvolve, if not to exploit the available source of light? What would be the difference between that and say designing an amplifier in order to reproduce sound? Wouldn't it be fair to say that the amplifier exists solely to reproduce the sound? So why should it be any different with the brain which, is just a means by which to capture/contain consciousness?
     
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  3. Oct 25, 2004 #2
    How, or why?

    We can be certain the amplifier had a creator.

    An ideal amplifier, yes, but this isn’t an ideal world and so unfortunately in practice they tend also to produce...

    We can be certain the amplifier had a creator.
     
  4. Oct 26, 2004 #3
    Everything which is alive has at least a rudimentary form of consciousness, whether it has a brain or not. So guess what? The brain is not necessarily the source of consciousness.

    Also, we have eyes which are the receptacle to light, we have ears which are the receptacle to sound, we have noses which are the receptacle to smell, we have skin which is the receptacle to touch, and we have taste buds which are the receptacle to taste, all of which are externally based sensations. So why should it be any different with the mind, the receptacle to consciousness?
     
  5. Oct 26, 2004 #4

    hypnagogue

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    On what grounds do you make this claim?

    In a physicalist evolutionary view, the brain is just an information processing device whose baisc purpose is:

    1) to integrate all the sensory information gathered by the eyes, ears, etc., into a coherent representation of the world; and
    2) to move the body in the environment on the basis of that representation, in ways that are generally advantageous to the organism.

    Without a brain, the eyes, ears, etc. wouldn't be of much use to organisms. They could still produce reflexive behaviors, but they could not produce flexible, intelligent behaviors in the absence of a brain. Thus, the brain provides obviously evolutionary advantages, and thus its evolution was favored by natural selection.

    I happen to believe that there is more to nature than the physicalist view indicates, but nonetheless it certainly assigns a coherent and useful purpose to the brain without having to invoke consciousness. To provide a successful critique of physicalism, you will have to pose a dilemma that physicalism cannot resolve satsifactorily. Unfortunately, the dilemma you pose in this thread is quite satisfactorily resolved by physicalism.
     
    Last edited: Oct 26, 2004
  6. Oct 26, 2004 #5
    Actually I have no problem with physicalism per se', I just see it as being incomplete, since it merely addresses the mechanistic side to things, and fails to take into account the experience of the (alleged) operator which is in control. Yet even in that sense it's hard to refute, since we're all bound to this temporal physical body while we're alive.
     
    Last edited: Oct 26, 2004
  7. Oct 26, 2004 #6
    consciousness must surely exist on a huge range of levels. where or why we as humans judge what it is to BE conscious is a very interesting question.

    for example, an extremely well programmed computer, or a planet, or any complex system for that matter, seem to have some sort of 'overriding' properties that in one way or another suggest something similar to consciousness, or if not, a constructor or 'higher' knowledge if you will.

    somebody please tell me how we as humans, with our collectively subjective view of the universe, could possibly 'know' for sure whether any other entity was 'conscious'. i imagine the only way to 'know' something is to 'be' it.

    the physicalists have a point, but i suppose it is in the interest of those who know more about existence, to try and 'enlighten' such a limited perspective.



    <-------i wiggle my finger and am affecting matter with my mind------->
     
  8. Oct 26, 2004 #7

    hypnagogue

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    I agree with you on this. However, the point is that physicalism already has a great theory of how the brain came to be, without invoking 'mind' (in the conscious sense) at all. There is no compelling reason to accept your mind-based argument of how the brain came to be, since physicalism describes the process more rigorously without having to mention mind at all (thus being more parsimonious as well as more rigorous).

    In short, asking questions about the brain and how it came to be is not going to get you any traction on the problem of consciousness. We already have a theory of the brain (loosely speaking) that makes perfect sense, and the fact that it makes no mention of subjective, experiential consciousness is a good indicator that this is not a fruitful approach to attacking the problem.
     
  9. Oct 26, 2004 #8
    And yet why wouldn't the brain evolve, if not to become the vessel of consciousness?


    And of course without the medium, conscsiouness itself (the fact that we're alive and aware), we wouldn't have the means by which to examine any of this now would we? In which case I think Science is putting the cart before the horse when it says subjective experience has little or no bearing on the matter.
     
  10. Oct 26, 2004 #9

    hypnagogue

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    I agree. A given person can have no solid empirical grounds to declare the existence of consciousness in sytems other than his or her own self (the old problem of other minds). Therefore, we must resort to using various tactics of logical induction and deduction to try to at least pose coherent and informed guesses as to what systems do and do not have consciousness. It is important that we try to place this process on sure logical footing, rather than simply assume the existence or non-existence of consciousness in various circumstances, as Iacchus did in his previous post. Assuming consciousness in fellow human beings is not much of a logical leap, and surely is the minimal assumption we must make in order to get anywhere, but extending the analysis to other systems becomes a dicier proposition the further we get from human-like systems.

    I don't think this is a fair portrayal. Physicalists are humans, and so they are just as knowledgeable about the basic experiential aspect consciousness-- in terms of what it is to be conscious, what it feels like to visually experience a sunset, etc.-- as any other person. They interpret the problem of consciousness differently, and some even try to write it off as a non-existent illusion, but even these people (I'm willing to bet) are just as conscious as you or I. They are almost definitely not zombies, all 'dark inside,' and thus they are just as knowledgeable and 'enlightened' in the important respects of the problem. The point of divergence is not the base facts, but what each party considers to be the logical consequences of those facts.


    Somewhat like Iacchus's effort, this is not the way to proceed. If you try to impress a physicalist with a statement like this, you will be summarily written off, due to the simple fact that the movement of your finger is entirely explicable in physicalist terms. The argument against the physicalist position must center on those aspects of reality that are not explicable by physicalism, and the very existence and nature of consciousness is plausibly one such aspect (whereas the evolution of brains and the movement of body parts are not).
     
  11. Oct 26, 2004 #10

    hypnagogue

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    I already explained this; see points 1) and 2) in my post above.

    It is logically coherent to imagine that we would have the means to examine the world without having subjective experience. Most people do not consider a desktop computer to be conscious, though functionally it does the same type of thing we do when we examine the world-- it performs logical operations on incoming information (inputs), and produces outputs.

    The concepts of computation, examination, awareness, etc., do not require any mention of conscious experience in order to be coherent. We know that conscious experience exists, and that it is intimately related to what we consider to be our own awareness, examination, etc. of the world, but the fact that these notions are logically coherent on their own changes the way we must approach the problem.

    The problem presents itself as one of how we can conceptually incorporate consciousness into an otherwise coherent and complete physical picture of the world, not one of how consciousness completes what used to be an incomplete or incoherent framework. To approach the problem in this latter way will not get one anywhere without a great deal of prior theoretical motivation, and vague intuitions will not do the job here. We must approach the problem with great respect for the integrity of the physicalist picture where it has already been well established.
     
  12. Oct 26, 2004 #11
    And yet this coherent picture you're talking about here would have never have come about unless there were conscious beings to establish it. The same scenario with the computer. All these things we are discussing here are by-products of the fact that we're conscious. So I don't see how you could possibly discount one's subjective experience, because that's really all we've got.
     
  13. Oct 26, 2004 #12

    hypnagogue

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    This is not a good argument unless you can establish that it is logically necessary for us to have subjective experience in order for the types of things we have done to have been done. The very existence of a coherent physicalist ontology that makes no mention of subjective experience undermines any attempt to establish that logical necessity.
     
  14. Oct 26, 2004 #13

    Les Sleeth

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    I don't think finger movement is "entirely explicable in physicalist terms." From brain to finger can be explained, but how the will of consciousness can trigger the brain is not understood. Because of this, I think Iacchus might be considered right to say "Everything which is alive has at least a rudimentary form of consciousness . . ." IF he hadn't added " . . . whether it has a brain or not" since life without some sort of nervous system seems to have no will. But even an amoeba, as primitive as its nervous system is, can will its body to move.
     
  15. Oct 26, 2004 #14
    What are you saying, that we're just to pretend like people don't exist? That doesn't sound very human to me? In fact it kind of takes the fun out of life. :confused:
     
    Last edited: Oct 26, 2004
  16. Oct 26, 2004 #15

    hypnagogue

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    The point is that physicalism can tell a complete, causally closed story about the finger movement without invoking consciousness. So trying to 'enlighten' a physicalist by saying "I move my finger with my mind" is somewhat like trying to impress a physicist by saying "God caused that ball to roll down the hill!" (I say somewhat, of course, because we actually do have very good reasons for believing in consciousness-- but that is besides the point in this specific instance.) Or, in a more metaphorical sense, it's like telling a community of well-off farmers, "Good news! I found a source of food!"

    The way to undermine an ontology is not to propose solutions to problems that that ontology has already solved. The way to go is to pose a problem that that ontology cannot solve, even in principle.

    As you and I both believe, the problem of consciousness is just such a problem that physicalism cannot solve, even in principle. To ply the problem against physicalism, though, one must naturally focus on the aspects of the problem for which physicalism has no answer: why it is that anything like subjective experience should exist at all, why physical systems should have some important place in the picture, etc. When it comes to questions of causality, physicalism is already robust, and attempting to critique its causal picture of the world is not an effective way to go.

    Actually, I consider myself a panexperientialist, meaning that I believe that something like consciousness (albeit in very primitive and alien forms) really does (loosely speaking) 'belong to' all physical phenomena. So I do not disagree with Iachhus on this basic point; I just don't want claims being thrown about without some degree of consideration.

    I believe a high-level cognitive phenomena such as 'will' or high-level physical phenomena such as nervous systems are not the kinds of things to look for when trying to uncover something that is proposed to be a fundamental aspect of nature, but that is a topic best left for another thread.
     
  17. Oct 26, 2004 #16

    hypnagogue

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    I'm not denying that human beings are conscious. All I'm saying is that there is a logical possibility from physicalism that sophisticated cognitive systems could exist without being conscious. You said:

    You seem to be trying to establish that consciousness is essential for things such as philosophies and computers to be created. I'm saying that it could be the case that these things could just as well have been produced by non-conscious agents.

    The motivation for this claim is roughly as follows:
    1) Physicalism gives us a complete and coherent causal story of nature.
    2) Physicalism does not need to invoke consciousness in order to sketch a complete and coherent causal story of nature.
    3) We can tell a complete causal story of all human history without mentioning consciousness (from 1 and 2). [Note that I say that we can tell a complete causal story, not a complete overall story. This distiction is important.]
    4) Therefore, it is possible (perhaps in our world, or perhaps only in a world with suitably adjusted laws) that the causal history of humans (and thus all the physical accomplishments of humans) could be duplicated by beings without consciousness (from 3).

    Even if we take humans to be an example of an instance where things have been created in virtue of consciousness, that does not imply that all such acts must be aided in some sense by consciousness.
     
  18. Oct 26, 2004 #17
    Except how do we know, when all we really know is that we're conscious? Do you really know anything outside of the fact that you're conscious? Can you think of anything outside of the fact that you're conscious? Try it some time ... and you'll soon realize that unless you're conscious, it's not possible.
     
  19. Oct 26, 2004 #18

    Les Sleeth

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    I'd grant it might not be the best way to argue for a non-physicalistic theory of consciousness, but I also don't think there is a physicalist explanation that solves the problem of the interaction of consciousness with the brain. Physicalists may not admit their theory falls short, but I believe it does.

    To solve the problem we'd have to observe a physical system which can move the finger, and we can observe that; and we'd have to observe the will that triggers the brain. As far as I know, will has never been observed except behaviorally (i.e., not in essence, as we can with the nervous system), yet it plays a key role in moving around the body.

    Looked at another way, if will is absent from the body, as when someone is in a coma, the body moves only by biological activity, such as from autonomic influences. If we remove nervous system responsiveness, as when a neck injury paralyzes someone, the person's will can still be fully intact but just unable to physically demonstrate it below the neck. So the existence of one isn't dependent on the other. Therefore, by empiricism's own standards, there is evidence missing that's needed to claim willed movement is purely physicalistic since we don't know if will is physical (because it's constitution can't be observed), and we have no verifiable explanation for how will and the nervous system interact.
     
    Last edited: Oct 26, 2004
  20. Oct 26, 2004 #19

    hypnagogue

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    Again, physicalism gives a straightforward example of how it is logically coherent (and thus, how it might be possible under suitable circumstances). Physicalism, in principle, can tell us a complete and coherent causal story of how philosophies and computers are made, and importantly, this complete and coherent causal story does not invoke experiential consciousness.

    The recipe is already there, given by physicalism; all it would take would be instantiation of the 'recipe' under suitable natural laws in order for it there to exist intelligent agents with the same causal propensities as humans, but nonetheless without experiential consciousness. The only way around this claim is if we can show that the type of brain described by physicalism must necessarily give rise to experiential consciousness, under all existential circumstances (whether actually existent or only logically possible) which physicalism describes accurately.

    Of course, such a tight equivalence between physical brain function and experiential consciousness quite plausibly does not coherently exist in any theory put forth, and there is further good reason that it cannot exist even in principle. That is to say, there is good reason to believe that physicalism alone cannot tell the complete story about experiential consciousness. If this is true, then it admits the logical possibility of intelligent cognitive agents who can do everything a human can do, but nonetheless are not conscious in the experiential sense.
     
    Last edited: Oct 26, 2004
  21. Oct 26, 2004 #20

    hypnagogue

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    We should be very careful about how we phrase the problem. Although physicalists might deny it, I would argue that physicalism does indeed not solve the general problem of the relationship between consciousness and the brain.

    But to phrase the problem specifically in terms of the interaction of consciousness with the brain is to already devote oneself to a rather strong theoretical position that may or may not be viable, at the expense of other possible theories.

    For instance, consider epiphenomenalism (the doctrine that experiential consciousness is caused in some sense by the brain, but does not affect the brain's causal dynamics). Epiphenomenalism is rather ugly and counterintuitive as metaphysical pictures go, and I don't believe a word of it. But it does appear to be logically consistent, and has the added benefit of respecting the causal closure of the physical, and so cannot be written off out of hand-- it could, perhaps, be true. If epiphenomenalism is right, then there is no problem of interaction of consciousness with the brain that physicalism must consider, although the problem of how the brain causes such experience is still a very real and substantial one.

    It is important to note here that there is at least one substantial theory of experiential consciousness (Gregg Rosenberg's Theory of Natural Individuals) that describes consciousness as casually relevant (i.e. not epiphenomenal) without assuming an interactionist ontology-- so it is not necessarily the case that one must choose between either epiphenomenalism or interactionist dualism.
     
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