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Early Modern: Locke on Personal Identity, Part 3

Part 3 of 3. What makes you the same person as the little kid growing up a number of years ago?  Is the identity of a person tied to the persistence of a body or a soul or something else entirely?  Can we even give any explanation at all of the persistence of a person?  Michael Della Rocca (Yale University) explores some of the puzzles and problems of personal identity that arise from the revolutionary work of the philosopher John Locke.

Speaker: Dr. Michael Della Rocca, Andrew Downey Orrick Professor of Philosophy, Yale University 

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  • leaf orange style avatar for user Randy
    A week ago I read an article that caused me to change my mind about something. The moment after I read it my beliefs changed which caused my attitudes and actions to change as well. Would Locke's account really say that I'm the same person even though I would respond differently to the same question now?
    (11 votes)
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  • leafers ultimate style avatar for user OwenBbowen
    doesn't this mean that if someone wrote down every thought and action they did and another person memorized that would the second person be the first person? because in the video a and b do not look the same.
    (2 votes)
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    • orange juice squid orange style avatar for user Daniel Rigal
      I don't think so. They would remember reading it or remember their imagination of what was described but they would not remember it as it actually happened. We don't fear that we are going to turn into another person just because we read their autobiography. In some sense we may become a bit more like them as we absorb some of the thoughts that influenced them but I don't think it goes much further than that.
      (3 votes)
  • marcimus pink style avatar for user Raymond Greenwood
    I am not understanding the branching problem. How can there be two memories of the the same past? Can someone give me an example of this? Also I have read that a portion of almost everyone's memory is completely false. Can anyone tell me how this would impact Locke's theories.
    (2 votes)
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  • leafers seed style avatar for user jennycqd
    Are Memory and Consciousness same?
    (3 votes)
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  • purple pi purple style avatar for user Jousboxx
    In the Brave Officer situation, maybe person C is identical to person A because he has some -- but not all -- of person A's memories. He might not remember stealing the candy, but surely he remembers something from his childhood?
    (2 votes)
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  • leaf blue style avatar for user mackendy.damis1991
    what is the difference between the person and the human being?
    (1 vote)
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  • orange juice squid orange style avatar for user Daniel Rigal
    The transitivity problem seems even worse than set out here:

    - Old Dave remembers being Young Dave so he is Young Dave.
    - Young Dave does not remember being Old Dave so he is not Old Dave.

    So we can't say A=B therefore B=A. So branching is not fundamental to our problem.

    So rather than identity, is this about incorporation?

    Old Dave incorporates Young Dave. Young Dave does not incorporate Old Dave.

    So:
    A = B + what happened since B
    For A later than B only.

    That would seem to solve the branching problem. The two copies are both the original person but have since diverged from eachother and from that original person.

    So I am not quite who I was yesterday. I am that person plus what I have done since, possibly minus what I have forgotten since.

    Does that make sense or is there some great big hole in it?
    (1 vote)
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  • leafers seed style avatar for user capgunMatt
    Does Locke define a person (as opposed to a man)? How can he simply say that the person is different but the man is the same? This would means that the person came into existence as soon as a memory was forgotten, just as would be the case for a man. So other than introducing a new concept to delay criticism, what is the definition of person that Locke uses?
    (1 vote)
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Video transcript

(intro music) Hi, this is Michael Della Rocca yet again, and still talking to you about the problem with personal identity over time, as it appears in the philosophy of John Locke. At the end of our last segment, we had gotten to the point of discussing what Locke's theory is. He accounts for personal identity over time in terms of the sameness of consciousness or memory over time. So what it is for a later Person, B, to be identical to an earlier Person, A, is for B to be able to remember A's thoughts and actions. This sameness of memory, this continuity of memory, is meant to be both necessary and sufficient. I ended by saying that there's a certain plausibility to this view (personal identity consisting in sameness of consciousness or memory), but there have been certain problems that have been raised for Locke's view from the very first moment that he introduced this view, and that have exercised philosophers a great deal since that time. I want to mention three puzzles or problems, and these are the three "BR" problems. There's the Breakfast Problem, the Branching Problem, and the Brave Officer Problem. So I want to discuss those three problems because they're illustrative of the power, and also the limitations, of Locke's view. First, I'm gonna talk about the breakfast problem. If sameness of consciousness, if memory, is necessary for personal identity over time, then I must be able to remember that earlier person's thoughts and actions, and if I don't remember, if I can't remember, that earlier person's thoughts and actions, then I'm not identical to that person. But this leads us to the breakfast problem. Intuitively, we might think that I can forget what I had for breakfast yesterday. In fact, I do forget what I had for breakfast yesterday. I can't do anything to jog my memory in this regard. So let's say I had breakfast yesterday, but I can't remember having breakfast yesterday. Since, for Locke, sameness of memory is a necessary condition for personal identity over time, then it follows that I'm not identical to the person that had breakfast yesterday in my kitchen, and that seems very strange. It doesn't seem that a new person comes into existence by virtue of the mere fact that I forgot what I had for breakfast yesterday. This seems to be a very stringent requirement on personal identity over time, and it's not clear how Locke can avoid this problem. One thing that Locke does say in trying to address this kind of problem is that he draws a distinction between what he calls a man, or a human being, and the person. And in a way, he bites the bullet in response to this problem. He says, "Because I don't remember "what was had for breakfast yesterday, "then I am not the same person "as the person who had breakfast yesterday "in my kitchen. "Nonetheless, I am the same human being, "or the same man, as had breakfast." So there's sameness of human being, sameness of human animal, sameness of man, over time here, but it's not the same person. So, there's literally different persons in my house. My wife will be very surprised, but there's literally different persons in my house on these two days, but it's the same man or the same human being. That's Locke in the way of biting the bullet. Yes, he admits that his account entails that there are different persons when you forget what you had for breakfast, but he thinks that that's okay because something in the neighborhood is right. There's the same human being, the same man, as he puts it, even if not the same person. That's the breakfast problem. The second BR problem is the problem of the Brave Officer. And this was an example that came up from Thomas Reid, a successor of Locke, in the eighteenth century. He raised this problem of Locke's account. Reid's objection turns on the two parts of Locke's view together. The part according to which sameness of consciousness or memory is necessary for personal identity over time, and the part according to which the sameness of consciousness or memory is sufficient for personal identity over time. And Reid's objection plays upon those two conditions together. So let's imagine this example, and this is the Brave Officer example. And we'll have three different times. So we have a person at Time 1 (this is person A), a person at Time 2 (this is person B) and a person at Time 3 (that's person C). Let's say that a certain person, earlier in his life when he was a child, he committed a certain kind of crime, he got in trouble at school for stealing some candy from the school cafeteria. That's T1. That's person A. Then at time T2, many years later, let's say fifteen, twenty years later, at Time 2 there's a person B, who is a Brave Officer (that's why it's called the "Brave Officer Problem") who wins a certain battle. He steals the flag from the enemy and wins a certain battle. It's the same person, we think, as the person who stole the candy fifteen years before he became a brave officer. Now, when he was a brave officer, he remembered stealing the candy. Right? He had a memory of that. Okay, he has this illustrious career as a soldier and as a member of the military, and then he is retired. And when he's a retired general (this is the later time T3, and it's person C), this retired general remembers winning the battle as a young man, as a twenty-two-year-old man, or whatever. He remembers winning the battle, but he's lost the memory of stealing candy when he was younger. So now, according to Locke's theory, the retired general, because he remembers the brave officer's action of winning the battle, the retired general, person C, is identical to person B, is identical to the brave officer. And person B, the brave officer, since he remembers what the little kid did, person B is identical to the little kid, he's identical to person A, who stole the candy. So C is identical to B, and B is identical to A. Now, it seems then by the most trivial property of the notion of identity, the transitivity of identity, since C is identical to B, and B is identical to A, it seems then that C is identical to A, that is, the retired general is identical to the little kid. But on Locke's account of personal identity, this cannot be the case, because for Locke sameness of memory is not only sufficient for personal identity over time, it's also necessary for personal identity over time, And in this case, the retired general doesn't remember A's actions. So, given Locke's account of personal identity, C cannot be identical to A because C doesn't remember A's actions. But given Locke's view that memory is sufficient for personal identity over time, and given the transitivity of identity, which Locke does not seem to want to deny, it follows that person C is identical to person A. So Locke's theory, as stated so far, seems to entail a contradiction, both that person C is identical to person A and that person C is not identical to person A. This is a big problem for Locke's theory. He doesn't address it, cause this problem wasn't raised to him in his lifetime, but it's a problem that contemporary versions of the Lockean view must spend a lot of time trying to address. So that's the brave officer problem, the second of our BR problems. And the final problem that I want to raise today is the Branching Problem. So, let's imagine that there's a case that persons can, like amoebas, divide. There can be fission of persons, like there is fission of amoebas. So let's have an earlier person, let's call it "A," and let's say that somehow it divides into two persons. You can imagine this kind of brain-splitting operation, where the two halves of the brain get put in two different bodies, or you can imagine some other kind of splitting operation, where you have two later persons, B and C, that each have some kind of continuity with the original person, A. Each of B and C remembers A's thoughts and actions. So there are two different competitors to be identical with the original person, A. At this later time, one of the competitors is B, who has A's thoughts and actions, but a different person at time T2, this later time, a different person, person C, also remembers A's thoughts and actions, so both B and C are competitors. They both are equally good candidates, it seems by Locke's account, for being identical to the earlier person, A. Yet it cannot be the case that each of B and C is identical to A, cause B and C are not identical to each other. Again, by the transitivity of identity, this would lead to a contradiction. So it can't be the case that both B and C are identical to A. But then which one is identical to A? Why favor B over C? What would be a sufficient reason for B to be identical to A rather than C? It would seem arbitrary which one of B and C gets the honor of being identical to A. Many philosophers think that neither one of those later people B or C gets to be identical to A. So then, in this case, despite the continuity of memory, there's too much continuity, and despite the great success in my memories carrying on, or A's memories carrying on, there's too much success, and so there's a failure of identity over time, and that seems to be an odd result too. As Derek Parfit, a famous philosopher who writes in this vein, says, "How could a double success, "twice the continuity, "result in a failure of personal identity over time?" This is the problem of branching, and philosophers have spent much time discussing this problem too. And that's the third of our BR problems that face Locke's account of personal identity. Now, as I said before, philosophical problems tend not to have a definitive solution. But they raise important problems for us, and they lead us in different view about ourselves and deeper views about ourselves. And although there aren't any definitive answers for these problems for Locke's view, it doesn't mean that Locke's view is ruled out. It means that this is an occasion for us to keep exploring and looking for deeper ways to understand the problem of personal identity, to make the next bit of progress in our understanding of this central aspect of ourselves. Subtitles by the Amara.org community