Phil 89: Williams on Personal Identity

Consider the following two stories.

Story 1

We remove your brain and put it in B’s body. B’s brain gets put in your body. Then we inflict pain on one of the two bodies. Which body would you rather have us torture? When Williams asks these questions, set aside any inclination you may have to be a “hero.” The way for us to explore our intuitions about personal identity is for you to imagine making these decisions selfishly. Most people would prefer us to torture the body their brain originally occupied, rather than the body it now occupies. That is, they believe that they would go where their brain goes.

Now, is it really important to preserve the specific neurons that make up your brain? If we replaced your neurons one by one, you’d still be the same person, wouldn’t you? So it doesn’t seem to be essential to you to keep those particular neurons. Rather, what’s crucial seems to be the information and neural patterns that your brain contains. We discussed in class whether this step is as straightforward as Williams presents it.

Suppose that, instead of moving your brain itself, we instead “scanned” your brain, extracting all that information (and at the same time wiping your brain clean), and then we implanted this information into B’s nervous system. Wouldn’t that be just as good as moving your brain? Let’s suppose we also put the information “scanned” from B’s brain into your original nervous system. Which body would you rather have us torture in that case?

sam brown, explodingdog

Here too many people are inclined to say “Torture my original body.” They believe that when their information is implanted into B’s nervous system, then they will be inhabiting B’s body. Even if their physical brain stays back in the original body.

Story 2

This story involves a number of steps. The first four possibilities are ones Williams also considers, but numbers a bit differently.

  1. Tomorrow we will torture you, perhaps by giving you a painful dental operation with no anesthesia. But we assure you that when the time for the operation comes, you won’t remember that you’re about to get it. Still, this operation seems a frightening prospect.

  2. We tell you that when the time for the operation comes, you won’t only have lost your memory that you’re about to get the operation. You’ll also have forgotten all the things you now believe and experiences from your past life. You won’t even remember who you are. This doesn’t seem to make the operation any less frightening a prospect.

  3. We don’t just change your beliefs and memories, but also change your interests, personality, character, and so on.

  4. When the time for the operation comes, you’ll have forgotten all of your previous beliefs and experiences plus you’ll have a whole new set of fabricated memories. You’ll think you’re someone else. And you won’t know about the upcoming operation. But come it will, and it will still be painful.

  5. This time, all the fabricated memories you’ll have will exactly match the beliefs and past life of some other person, B. In fact, this is how we’ll implant those memories: we’ll read the patterns out of B’s brain, and copy them into your brain. (We’ll leave B’s brain as it was.) Then comes the painful operation. Does this make the operation any less frightening a prospect?

    No, it makes it seem like you’re about to suffer a radical psychological change, and then get a painful operation! If you knew that you were going to suffer this psychological change, and there was nothing you could do about that, but you had the option to do unpleasant chores for a few hours beforehand, to make the operation less painful, wouldn’t you choose this?

  6. In the last step, we do the exact same thing to you (or more neutrally, to your original body) that we did in step 4. But we also make B suffer a corresponding psychological change. So B thinks he’s you, and you think you’re B. But you, thinking you’re B, get the painful operation, whereas B, thinking he’s you, goes free. Doesn’t that suck?

Williams is relying on an important intuition to justify this last step. This is the intuition that identity is an intrinsic matter. Whether two stages A* and Z* count as parts of a single person should just depend on what A* and Z* are like in themselves, and how they are connected to each other. It should not depend upon what’s going on with other bodies, elsewhere in the universe. (Compare: if we want to know whether two innings are part of a single baseball game, we should only need to look at those innings, and how they’re connected (this will include the innings in between them). We shouldn’t have to look at what’s going on in other ballparks.) So if A and the A-body person can count as being the same person, in step 5, then changes we make to the B-body person in step 6 should not be able to alter that.

Here is how Williams expresses it:

[In the last step] there is absolutely no difference at all in what happens to [A], the only difference being in what happens to someone else. If he can fear pain when (v) is predicted, why should he cease to when (vi) is?… The A-body person in (v) is, in character, history, everything, exactly the same as the A-body person in (vi); so if the latter is not A, then neither is the former… [If A just does not exist in step (5)] this would certainly explain why A should have no fears for the state of things in (v) — though he might well have fears for the path to it. (p. 192)

When we tell this second story, most people feel at least some pull towards saying that they would stay in the original A-body, even to the end of the story.

If you want to resist that, consider where you’d want to draw the line. At what step do you think the person in the A-body would no longer be you, and thus that you would no longer experience the pain when the A-body gets tortured? (Maybe this will be because no person who still exists is you: you have not survived. But at least you’ll not have to experience the painful operation.) If you can identify the step that you think makes a difference, can you explain why the difference introduced at that step has that effect?

In class, we discussed some different ways one might respond to this challenge. But for these notes, I’ll go along with Williams’s own reaction to Story 2, namely that you would or at least might still be in the A-body. As I said, many people report feeling at least some intuitive pull in that direction.

Lessons Williams Draws

  1. One lesson of Williams’s discussion is that — in Story 2 — I seem to be able to imagine all my memories, beliefs, interests, personality and character changing and yet I still exist as the same person. That’s because I could undergo those changes and still feel the changed person’s pain. If I can feel their pain, then presumably I am that person. This suggests that the psychological characteristics that distinguish me from other people are not essential to me: I don’t need to retain them in order to remain numerically the same existing person.

  2. Probably the most interesting thing in this article is that, as Williams observes. Story 1 and Story 2 seem to describe the very same situation. At least, they could involve technicians doing the very same things to A’s and B’s bodies/brains. It’s just that the situation is presented or described differently. When we heard Story 1, we were inclined to say that we went where our information goes, even if our brain stayed behind. Most people would prefer to have the body with their information in it go free, and have the body with their original brain in it get tortured. When they listen to Story 2, though, many people have a different reaction. They’d prefer to let the body with their original brain in it go free, and have the other body be tortured. Even if that other body happened to have their brain patterns implanted in it. This illustrates how our intuitions can pull us both ways. When we consider what seems to be the very same situation, we can have very different reactions to it, depending on how it’s described. Sometimes we think the Lockean picture is right: we go where our psychological “patterns” or “information” goes. Other times we think we stay with our original brains or bodies, even if their psychologies are radically manipulated.

  3. The last pages of Williams’s article (starting at p. 193) discuss whether it makes sense to think there could be indeterminate or borderline cases of being the same person as someone who exists in a future situation.

    Williams allows that it makes sense to have indeterminate expectations in some cases, for example if I know that “one out of us five is going to get hurt,” or if I know that “something nasty” is going to happen to me, but I don’t yet know specifically what it will be.

    But he thinks that the stories he’s told are different from that. He thinks that with these stories we can’t make sense of our ambivalence and uncertainty about what’s going to happen in the same way. If some future person will feel pain, then either I will be that person and so be the one feeling that pain, or I won’t. It doesn’t make sense to say I sort-of will and sort-of won’t. There has to be a definite fact: Someone will be feeling that future pain. Will it be me, yes or no? Williams is not saying I have to be able now to know which of the possibilities will come to pass.

    When we look at Parfit next week, we’ll see an opposing view about this. He thinks it does makes sense that there could be no definite answer to such questions, just as it might make sense to say there’s no definite answer as to whether the Ship of Theseus still exists (and if it does, where it is).

    Another thing Williams argues is that when it comes to persons, “conventionalist decisions” about what to say, like lawyers debating who owns some property or what counts as the same ship, seems wrong-headed. Again, Parfit will take the other side.

  4. Williams closes his paper by suggesting that our intuitive reactions to the second story are more trustworthy, and so his own favored view — which he defends in other papers — is that personal identity requires keeping the same body.

    Does he say enough in this article to persuade you in that direction, too?