Hume on Personal Identity

Hume on Personal Identity WADE L. ROBISON Brain transplants are now medically feasible, but the whole head would probably have to be grafted at the same time, said David Hume, MD, chief of the department of surgery at the Medical College of Virginia, and a pioneer of organ transplants, during a press conference in Melbourne , Australia. The donor of the brain in such an operation, according to Dr. Hume, would, in fact, be the recipient as the mind would take over the body to which it was grafted. American Medical News 1 DR. HUME SURELYHASHOLDOF A PROBLEMof practical importance: Who is to pay? He opts for billing a person who has been attached to a new body and would probably present two bills since, after all, the patient did receive two operations. Whatever one may think of Dr. Hume's solution, he does have hold of a philosophical problem, that of personal identity. This is not, as David Hume the philosopher points out, the problem of what distinguishes persons from other kinds of things. Descartes does that in making what Hurne thinks is the "absolutely unintelligible" claim "that thought was the essence of mind" (A25). ~It is rather the problem of what distinguishes a particular person from other persons and other things "since every thing, that exists, is particular" (A25). s Dr. Hume also has hold of one of the essential dements of any solution: he knows, as one hopes any doctor learns early in his career, that one does not count persons simply by counting bodies. But he has drawn a mistaken inference: one must count persons by counting only something else, viz. minds. For the good doctor this may mean counting only part of a body, for he may mean that the brain is the mind. But for David Hume, who shares the inference, the distinction is complete: minds are not bodies. The problem of personal identity is thus for him the problem of distinguishing particular minds from one another and other things: personal identity is identity of a mind. If Dr. Hume's donor and recipient are the same for Hume, therefore, it must be that we can truly say of one that it is the same mind as the other. But when we say that something is the same with itself, Hume argues, "we really shou'd mean nothing, nor wou'd the proposition contain a predicate and a subject" if we did not "mean, that the 1 Quoted by The New Yorker, December 12, 1970, p. 196, with the following question: "Who gets the headaches?" 2 References to Hume's works have been put into the text, using "T" for the Treatise (the Selby-Bigge edition), "E" for the Enquiry (the Selby-Bigge edition), and "A" for An Abstract o/ a Treatise of Human Nature (the Keynes and Sraffa edition, reprinted by Archon Books, 1965). The letter is followed by a page number so that A25 means Abstract, p. 25. 8 It is difficult to know how seriously to take these remarks. If generalized they would imply that we can never distinguish any kind of thing from any other kind of thing. The fact remains, however, that Hume thinks the problem of personal identity the problem of distinguishing one person from another. [181] 182 HISTORY OF PHILOSOPHY object existent at one time is the same with itself existent at another" (T200-201). A condition then for the sense of the "proposition, an object is the same with itself'" is that "an object" refer at one time to what "itself" refers to at another. "An object" and "itself" must thus refer to the same object, but what are the criteria by which one determines what is to count as the same object? Hume is explicit: "The principle of individuation is nothing but the invariableness and uninterruptedness of any object, thro' a suppos'd variation of time..." (T201). We can intelligibly say that the donor is the same as the recipient only if, first, his existence during the operations has been uninterrupted by death and resurrection and, second, he has remained invariable through that time, a variation consisting in the addition or loss of qualities (T96; see...