Personal Identity

Week of: 
December 16, 2007
What is it: 

What is necessary for a person to survive over time?  Is it the continued existence of the living body?  Or is it just the living brain?  Or is it one's psychology, which might persist even without one's original brain in a computer or in an entirely new brain?  How important are questions of personal identity for ethics and rationality? John and Ken are joined by Raymond Martin, Professor of Philosophy at Union College and co-author of The Rise and Fall of Soul and Self: An Intellectual History of Personal Identity.

Listening Notes: 

Ken and John begin this week’s episode by discussing what philosophers mean by personal identity, and why they think such a thing exists. Ken proposes a simple definition: personal identity is simply the same thing we mean when we talk about the identity of two objects, where the objects just happen to be people. But John disagrees. He argues that people mean something very different when they refer to the identity of persons. He thinks there’s a psychological sense of identity that is most important to people when they are referring to who they are. Even still, Ken counters, there is always just one person who is undergoing changes over the course of his/her life. So what does this psychological sense matter? Thus begins the debate about personal identity.

At this point, Raymond Martin enters into the discussion to try and help clear up the confusion between Ken and John. Ken queries Raymond as to why he should plan for the future, why he should care about the old guy he is going to grow into. Caring about ones future self can become a very confusing concern when you consider different thought experiments regarding personal identity. By looking at the intuitive judgments people have in response to these experiments, it is possible to understand what matters most to individuals when they are acting out of concern for their future self. Ken, John, and Raymond enter into a trying debate about psychological and bodily criterions of personal identity, and attempt to discern whether there is a correct answer about which captures the essence of personal identity best. What happens when your body undergoes drastic changes, do you remain the same person? What if those changes effect your mind, like in the case of Alzeimer’s disease?

At this point, the discussion turns to questions about self governance and autonomy.  The ethical landscape of questions related to the personal identity and wishes of people who have undergone grave psychological changes because of disease proves to be challenging terrain. Ken and John, in addition to our guest Raymond, attempt to sort out and make sense of the implications of personal identity for rationality and morality.

  • Roving Philosophical Reporter (SEEK TO 00:04:23): Zoe Corneli takes us on a tour through Hollywood and its different representations of personal identity. She presents the deep questions about the nature of personal identity, and what our bodies and brains say about who we are from “Being John Malkovitch”. “Freaky Friday,” the “Young Frankenstein”, and “Star Trek” all address how identity is malleable to the extent that we can modify our brains.
  • Ian Shoales The Sixty Second Philosopher (SEEK TO 00:48:38): Ian Shoales speeds us through a discussion of cognitive dissonance and wishful thinking, and the relationship to personal identity. Cults, God, Relationships, Iraq, and Los Angeles—Shoales leaves no topic out of this sixty second report.

Raymond Martin, Professor of Philosophy, Union College

Related Resources: 

Bower, Bruce. “Self-Serve Brains”. Science News, Vol. 169, No. 6, Feb. 11, 2006, p. 90.
Dennett, D. “Where am I?”.
Hughes, James, J. “Brain Death and Technological Change: Personal Identity, Neural Prostheses and Uploading”.
"Identity/Identity formation". Encyclopedia of Psychology.
Martin, Raymond and Barresi, John. Personal Identity.
Olson, Eric T. "Personal Identity".  Stanford Encyclopedia of Philosophy.
Perry, John. Personal Identity.
Rorty, Amelia. The Identities of Persons.
Staying Alive: The Personal Identity Game. (An online game.)  The Philosopher’s Magazine.
Articles by guest Raymond Martin:

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