Personal Identity and Fractured Selves: Perspectives from Philosophy, Ethics, and Neuroscience

5 Personal Identity and Choice

chapter five Personal Identity and Choice Carol Rovane, Ph.D. It was John Locke who formulated the problem of personal identity as it is understood by contemporary philosophers (Locke 1975). He asked whether personal identity is the same as human identity, and he answered no, on the basis of the following interrelated considerations. First, he o≠ered a definition of the person as “a thinking, intelligent being that has reason and reflection and can think itself as itself in di≠erent times and places” (335). He went on to note that persons are aware of themselves and their thoughts through consciousness. He concluded that the life of a person extends exactly as far as the person’s consciousness extends—by which he meant the person’s reflexive awareness of its existence over time through memory. It would seem to follow directly from these considerations that the life of a person is not to be equated with the life of a human being. The life of a person, in Locke’s sense, would seem to begin not with biological birth but, rather, with the dawning of selfconsciousness , which comes much later in human development. Likewise, it would seem that the life of a person may also end before biological death, if personal consciousness is lost sooner than that, either through amnesia or through a total loss of consciousness. Locke also raised the possibility of some- thing like dissociative identity disorder, with an imaginary case in which two distinct consciousnesses—a “day person” and a “night person”—alternate within the same human being. But the possibility that held the greatest interest for him was much farther removed from the actual human condition. It is the purely hypothetical possibility that he raised with his famous thought experiment about a prince and a cobbler. The thought experiment asks us to imagine that the consciousnesses of a prince and a cobbler are switched, each into the other’s body, and to work out who would be who after the switch. Locke took it to be obvious that the prince would be the person with the princely consciousness and the cobbling body and the cobbler would be the person with the cobbling consciousness and the princely body. And he took this to be a decisive ground for concluding that personal identity and human identity are two di≠erent things. In my view, this last possibility—of “body-switching”—lies too far beyond the actual facts of the human condition to be of interest to anyone but writers of science fiction. But many philosophers do not share my dismissive attitude . They insist that it is instructive to think through how our concept of a person would apply in imaginary cases like the case of the prince and the cobbler . As a result, an entire literature of thought experiments about personal identity has arisen in which we are asked to give intuitive responses about who would be who in various counterfactual conditions in which persons allegedly survive in new and di≠erent bodies, such as brain transplants, brain reduplication , brain reprogramming, and so-called brain zippering procedures.1 One di∞culty with relying on such thought experiments is inconsistency of response : not everyone finds it intuitively plausible that the same person could persist in a new and di≠erent body. But even if everyone’s intuitions accorded with Locke’s, it would still be precipitate to conclude that he was right to draw a distinction between personal and human identity. Although we can easily conceive the possibility of body-switching, future science might eventually tell us that it isn’t really possible because it is ruled out by the laws of nature —much as physics tells us that we can’t fly like Peter Pan even though we find that easy enough to imagine, too. If the entire case for Locke’s distinction between personal and human identity rested on his thought experiment about the prince and the cobbler (and other similar thought experiments), then I would recommend that philosophers leave it to science to settle the matter. But as it happens, there are in94 Philosophers Hold Forth teresting grounds on which to a∞rm a version of his distinction that are not hostage to the deliverances of future science. To uncover these grounds, we need to explore a distinction that Locke himself glossed over in his own account of personhood and personal...