John Perry: A Dialogue on Personal Identity and Immortality

Third Night:

Dramatis Persona:

Gretchen Weirob (W): Philosophy Prof. dying from injuries from a motorcycle accident.

Sam Miller (M): Chaplain & friend of Weirob's

Dave Cohen (C): Former student of Weirob's.

Julia North's 'body transplant'.

P38: C: "Dr. Mathews . removed the brain from Julia's head and placed it in Mary Frances', slicing the nerves, and so forth . The survivor of all this was Julia, as everyone agreed ­ except, unfortunately, Mary Frances' husband."

P39: C: "the relevance of this case is obvious. Julia North had one body up until the time of the accident, and another body after the operation. So one person had two bodies. So a person cannot be simply identified with a human body."

Weirob and brain transplants

P39: Weirob reveals, to the shocked dismay of the others, that she had the chance to undergo a similar procedure, but turned the opportunity down.

P39: W: "I think The survivor of the operation involving Julia North's brain was Mary Frances Beaudine, and the survivor of the operation using my brain would not have been me."

P40: W: "In my opinion, the effect of the operation was that Mary Frances Beaudine survived deluded, thinking she was someone else."

Cohen's Conventionalism and Weirob's Realism:

40-1: C: "This is a case in which two criteria we use to make judgements of identity conflict. Usually we expect personal identity to involve both bodily identity and psychological continuity. We have to choose which criterion is more important. It's a matter of choice how we use our language, how to extend the concept 'same person' to a new situation. The overwhelming majority of people in the case took the survivor to be Julia. That is, society chose to use the concept one way rather than the other. The Supreme Court is not beside the point. One of their functions is to settle how old concepts should be applied in new circumstances. They are fallible on points of fact, but they are the final authority on the development of certain important concepts used in law. The notion of person is such a concept."

41-2: W: "Now this is clearly absurd. If I were correct, in the first place, to anticipate having the sensations and thoughts that the survivor is to have the next day, the decision of nine old men a thousand or so miles away wouldn't make me wrong. And if I was wrong to so anticipate, their decision couldn't make me right. How can the correctness of my anticipation of survival be a matter of the way we use words? If it is not such a matter, then my identity is not either. My identity with the survivor, my survival, is a question of fact, not of convention."

HJ: Is this realism about survival justified, and if so, should it be tied immediately to questions of personal identity?

Why think that a person with your brain and another's body would be you?

P42-3: Miller and Cohen return to endorsing the idea that memory is sufficient for identity and the brain transplants preserve memory. Weirob then suggests that if such an account should be able to explain why personal identity is important in terms of why memory is important.

HJ: note that Weirob never makes an effort to answer a similar question in terms of the importance of the body.

43-4: C: "Those properties of persons which makes persons of such great value, and mark their individuality, and make one person so special to his friends and loved ones, are ultimately psychological and mental. One's character, personality, beliefs, attitudes, convictions ­ they are what makes every person so unique and special. A skinny Gretchen would be a shock to us all, but not a Gretchen diminished in any important way. But a Gretchen who was not witty, or not gruff those would be fundamental changes."

HJ: Note that all aspects of the personality plausibly associated with the brain are now attached to the 'memory theory'.

HJ: Does this suggest that Prozac or Ritalin brings into being a new person rather than helping an old one?

44: W: "So on two counts you favor the memory theory. First, you say it explains how it is possible to judge as to one's identity, without having to examine one's body. Second, you say it explains the importance of personal identity."

45: W: "We all agree that the fact that the survivor of this strange operation would seem to remember doing what I have done . We all first agree hat this much does not make her me. For this could all be true of someone suffering a delusion, or a subject of hypnosis."

45: C: But in the case of the body transplant "the same brain was involved in the perception of the events, and their later memory. Thus we have here a causal chain of just the same sort as when only a single body is involved. That is, perceptions when the event occurs leave a trace in the brain, which is later responsible for the content of the memory. And we agreed, did we not, that apparent memory, caused in the right way, is real memory?"

Brain Rejuvenation:

46: Weirob brings up a new experimental process called 'brain rejuvenation' in which 'fresh' duplicates of our brains can be reliably produced so that "the causal process involved is no less reliable than ordinary memory."

46-7: Weirob then asks whether you could survive having your old brain replaced with one of these 'rejuvenated' ones. Miller is inclined to say yes, but Cohen rejects the suggestion realizing that this would allow for single persons to be multiply realizable if many 'rejuvenated brains' were created. Cohen concludes: "Duplication of brain does not preserve identity. Identity of the person requires identity of the brain." (47).

47-8: Weirob brings up case were her brain was put in a body (A) while a rejuvenated brain was placed in another body (B). The others are committed to (A) being identical to Weirob while (B) is not . But such a conclusion, according to Weirob, strips the memory theory of its two advantages (explaining why we find identity important, and how we identify ourselves upon awakening. Upon awakening Weirob (A) would have no way of knowing whether she was the actual survivor or the duplicate, and both Weirob and the duplicate would have the same character traits that are important to others.

48: W: "Gretchen-A is no more like me than Gretchen-B. So there is nothing in your theory after all to explain why anticipation is appropriate when we have identity and not otherwise."

Body is all Weirob knows and has

48: W: "You said that I had an irrational attachment for this unworthy material object, my body. But you too are as irrationally attached to your brain. I have never seen my brain. I should have easily given it up for a rejuvenated version, had that been the choice with which I was faced. I have never seen it, never felt it, and have no attachment to it. But my body? That seems tome all that I am. I see no point in trying to evade its fate, even if there were still time."

Cohen's Pragmatism

49: C: Even if the body is essential, Suppose "The survivor takes herself to be you, and thinks she made a decision before the operation which has now turned out to be right. She is happy. Your friends are happy. Who would be worse off, either before or after the operation?

49: C: "Suppose even that you realize that identity would not be preserved by such an operation, but have it done anyway, and as the time for the operation approaches, you go ahead and anticipate the experiences of the survivor. Where exactly is the mistake? Do you have any less reason to care for the survivor than yourself? Can mere identity of body, the lack of which alone keeps you from being her, mean that much? Perhaps we were wrong, after all, in focusing on identity as the necessary condition of anticipation ­"

49: M: "Dave, its too late."