PERSONAL IDENTITY NOTES

Introduction

The general question we're concerned with: what makes me the same person across time?

X and Y are qualitatively identical iff they have exactly similar qualities.

X and Y are quantitatively identical iff whatever is true of X is true of Y and vice versa.

The Yacht Puzzle: Which of these yachts is the same yacht (quantitatively) as the one I left you to take care of?


Why do we need a criterion of personal identity in place? Three reasons:

  1.   __________________________________

  2.   __________________________________

  3.   __________________________________




FIRST NIGHT (THE SOUL CRITERION)

Weirob wants the comfort of knowing that it's possible to survive her death. By "possible," she means logical possibility = not conceptually incoherent (not involving/implying a contradiction).

FACT: my body will eventually cease to exist. Thus, given this fact, how could I still exist?

This is a materialist conception of the "I." So she holds the Body Criterion: X at t1 is the same person as Y at t2 iff X's body is the same as Y's body.

Weirob wants an alternative theory of identity that: (a) provides a means for surviving the death of her body; and (b) does not yield a contradiction or absurdity.

Miller's claim: what makes you you is an immaterial soul. So he holds the Soul Criterion: X at t1 is the same person as Y at t2 iff X's soul is the same as Y's soul.

Objections/Questions to the Soul Criterion:

A.   _________________________

B.   We cannot use this criterion to reidentify people.

Weirob's Reductio:

  1. Suppose the Soul Criterion is true.
  2. If the S.C. is true, we could never have the grounds to judge that X is the same as Y.
  3. But sometimes we do have the grounds to judge X is the same as Y. [CONTRADICTION]
    _________________________________
  4. Thus, the S.C. is false.

Miller's Response: __________________________________

Weirob's Rebuttal: __________________________________

Miller's Response: ___________________________________

Weirob's Rebuttal:

(1) _________________________________

(2) _________________________________

So you cannot know, even in your own case, if:

(a) _____________________________________,

(b)______________________________________,

(c) ______________________________________,

(d) ______________________________________, or

(e) ______________________________________

Miller's Reply: Mind as intermediate link between body and soul (where mind = psychological characteristics).

Weirob's Rebuttal: _________________________________________________




SECOND NIGHT (THE MEMORY CRITERIA)

If the Soul Criterion's not going to work, it seems we've got two options: (1) identify persons with bodies (Weirob's view); or (2) identify persons with their psychological features.

Miller's Thought Experiment:

Suppose we grant his thought experiment. What would this mean? That there's no ___________ underlying personal identity, i.e., it involves neither ________ nor _________ (according to Miller). E.G., the baseball doubleheader.

So a person is simply a _______ comprised of its ______________, and not some underlying ______________. What makes you you is a __________________________ (a person-stage). And what comprises these?

Miller now offers Memory Criterion #1: X at t1 is the same person as Y at t2 iff Y remembers the thoughts and actions of X.

Problems with MC#1

1.   __________________________________________________

The Brave Officer Case:

Reply:

2.   ___________________________________________________

Delusion/Hypnosis:

Reply:

3.   This Criterion is _______________.


So now Cohen jumps in with Memory Criterion #2: X at t1 is the same person as Y at t2 iff: (1) Y seems to remember the thoughts and actions of X, and (2) Y's seeming to remember is ________________________________.

So real memories must have an ____________________________.

The memory must be caused by __________________________________.

The right way = ________________________________________

The wrong way = ________________________________________

Implications/Problems with MC#2

1.   ________________________________________

Response: It all depends on what you mean by ________________________.

Perhaps all that matters is that the storage of information is ___________. So compare the normal case vs. the heavenly case:

Normal Case: ____________________________________________

Heavenly Case: ___________________________________________

So the analogy would be as follows: _________ = ___________

2.   Duplication

The transitivity of identity: if A=B, and A=C, then B=C.

Cohen now offers a third version of the memory criterion: Memory Criterion #3: X at t1 is the same person as Y at t2 iff: (1) Y seems to remember the thoughts and actions of X; (2) [CONDITION 2 OF MC#2]; and (3) __________________________________.

Problem with MC#3

This view is __________. Whether or not you're the same person would change as _____________________________.




THIRD NIGHT (THE BODY CRITERION)

Weirob's View: I am identified with my body. But Who is Julia?

At this point, everyone's assuming there are only two possibilities: the source of personal identity is either the brain (the seat of psychology) or the body.

Cohen's view: Julia got a _______ transplant. His argument, then:

  1. If the source of personal identity is the body, then one person can't have two bodies.
  2. Julia had two bodies (support? ____________________)
    ___________________
  3. Thus, the source of personal identity is not the body (i.e., it is the brain).

Weirob's view: Mary Frances got a ________ transplant. Her argument, then:

  1. If the source of personal identity is the brain, then one person can't have two brains (2 psychological sets).
  2. M.F. had two brains (support? ___________________)
    _____________________
  3. Thus, the source of personal identity is not the brain (i.e., it is the body).

But how do we choose who's right?

One possibility is convention. Weirob's problem with this:



Cohen and Miller thus retreat back to a different version of MC#2, one according to which the "right way" = "same brain." The brain houses personal identity because it houses memories.

Problem? ____________________________

Will the survivor be you or a different person?

  1. The survivor is you?

    Problem: __________________________

  2. The survivor is a different person?

    Problem: ____________________________




    A TENTATIVE SOLUTION TO THE PROBLEM OF PERSONAL IDENTITY

    I.   Problems with the Body Criterion

    Weirob assumes all questions of personal identity must have determinate answers (either I will survive or I won't).

    But consider the Physical Spectrum:



    What would Weirob say about the case at the far end of the spectrum, where 100% of my body is destroyed and replaced?


    What would she say if 1% of my body were destroyed and replaced?


    What about cases in which 30%, 50%, or 70% is destroyed and replaced? Where exactly is the borderline between existence and non-existence?



    II.   Problems with All the Criteria

    All four theories make two important assumptions: (1) all questions of identity must have determinate answers; and (2) personal identity is what matters to us in survival and is the relation justifying our future concern/anticipation. But both assumptions are problematic.

    A.   The Physical/Psychological Spectrum:


    This spectrum reveals that no theorist of identity who assumes (1) has a plausible answer to this case.

    So what does this mean?



    B.   Fission

    Four options:

    1. I do not survive?

    2. I survive as B?

    3. I survive as C?

    4. I survive as both?

    So what does all of this mean?

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