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Personal identity and materialism

  1. Feb 20, 2005 #1


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    If we literally are our material bodies (brain included), does that mean that when all our atoms at this point in time are fully replaced by new atoms, the person we are now is dead and there's a new person... with the same memories.

    I read online that 98% of our atoms are replaced in a year.
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  3. Feb 20, 2005 #2


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    No the identity persists because, first, the replacement is gradual, not all the atoms (or cells) are replaced at once, and second, because brain cells retain their identity and function over long periods of time, and it's those functions, and the processes they compose, that constitute our personal memories and hence our personal identity.
  4. Feb 20, 2005 #3


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    But who or what is having the experience of memory? Is it matter?

    I agree the memories are the same. My question is about the entity that is experiencing the memories.
  5. Feb 20, 2005 #4
    The entitiy who experiences the memories is not matter, it is mind. Materialist believe there is only matter, epiphenomenalist believe (like me) believe that the mind exists as a distinct substance (not matter) that is a by-product of the matter processes in our bodies; that matter affects mind but that mind cannot affect matter (because mind is non physical).
  6. Feb 21, 2005 #5
    The confusion arises from a bad phrasing of the question, learningphysics. The "entity" is a (socially) convenient way of referring to a series of memories, personality traits, etc -- similar, or otherwise -- that can all be attributed to the same collection of molecules. The entity doesn't "experience" the memories, but is partially composed thereof.

    SelfAdjoint is right that the function is what is important (the patterns of interaction among the neurons, rather than the neurons themselves). What I'm saying is that there is no singular, indivisible being that "experiences" these functions. Rather, the thing you think of as a "singular, conscious entity" is actually (partially) composed of those interactions among neurons.
  7. Feb 21, 2005 #6


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    There is such a thing as an experience right? Is it your position that there is an experience, but there is nothing that is having the experience?
  8. Feb 21, 2005 #7


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    I agree with you that mind and matter are distinct, and related. But I don't believe mind arises as a result of physical processes.
  9. Feb 23, 2005 #8
    There may be the process of experiencing (and that would depend on your definition of "experience"), but there are no singular (or, if you prefer, "finished") "experiences". And, yes, I'm saying that there is no singular entity (self) that is going through the process of experiencing (except in the social sense of there being one "person", and all the processes of experience are occuring within that "person"'s body).
  10. Feb 26, 2005 #9
    I think we are in basic agreement. I also note that this thread started with the problem of continuity when most of the atoms in the body are fully replaced. Implicit in that first post is the idea that we are that body - an assumption I reject, but I hasten to add: we are not "souls" or any other miracle that violate the physical laws.

    If neither body not soul, what are we? My answer is in the attachment. It is an answer to the conflict between the material body, which is governed by the laws of physics, (and thus can at best have the illusion of free will) and the nearly universal belief that we really do make genuine choices (Have what I call Genune Free Will, GFW.)

    Take a look at new thread: "What Price Free Will?" for additional discussion of how much and what one must pay to resolve the conflict between GFW & Physics. Read the price I was willing to pay in the attachment. (here or there)

    Attached Files:

  11. Mar 1, 2005 #10


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    By experience, I mean feelings, sensations, sights sounds... qualia.

    Can there redness, or pain or pleasure without something that is seeing redness, or feeling pain or pleasure?

    I'm curious as to why you used the word "singular".
  12. Mar 3, 2005 #11
    I agree with most of this, but try to avoid the term Mind. (Instead I use "I" or "me" etc. in quotes to distinguish my psychological "self" from my physical body.) As described in attacment to post 9 of this thread "I" an not physical, but exist as part of a very complex real-time simulation of the physical world. Where we differ is I do not agree with "mind cannot affect matter (because mind is non physical)" "I" an not physical, yet right now "I" am causing my body to hit keys on the keyboard. How did your post get typed?

    PS this thread seems to be dying, I am trying to help it live, but if it dies, please come over and participate in thread "What Price Free Will," but be warned that the posts there are tending to be long and thoughtful exchanges. If you enjoy the strange idea/view stated in attachment to post 9, take a look at the stranger one I am defending in "Time does NOT Exist - Math Proof" and participate there also. All three threads are related.
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