Pursuant of a memory theory of personal identity, Sydney Shoemaker argues that personal identity does not imply, and therefore does not consist in bodily identity. In the canonical example of body transfer, Shoemaker describes a case in which

…by a surgical blunder (of rather staggering proportions!) Brown's brain gets into Robinson's head. When the resulting person, call him 'Brownson', regains consciousness, he claims to be Brown, and exhibits detailed knowledge of Brown's past life, always reporting Brown's deeds and experiences in the first person. It is hard to resist the conclusion that we, viewing the case from the outside, ought to accept Brownson's claim to be Brown, precisely on the basis of the evidence that he remembers Brown's life from the inside. (Shoemaker 78)

Our inclination to make a judgment of personal identity in favor of Brownson's memory claims gives inductive strength to the Lockean memory theory of personal identity; in fact, the Brownson case is a reformulation of one of the examples Locke gives in support of his memory theory, in which a prince and a cobbler exchange souls or consciousnesses and the result is a prince in a cobbler's body and vice versa. Although the Brownson case gives reason to question whether personal identity consists only in bodily identity, it strikes us as compatible with bodily theories of personal identity because Brown and Brownson share a brain. On the other hand, if we conclude that Brownson is Brown, and if by 'body' we mean body without the brain, Shoemaker's example should be considered a case of body transfer ('superficial case') – one person has some body at some time, and the same person has a different body at a different time. This possibility is incompatible with any superficial bodily theory of personal identity, which would by definition hold that sameness of superficial body implies sameness of person.

Williams' Challenge

In "The Self and the Future," Bernard Williams presents what he considers to be a "less radical" (Williams 180) variant of the procedure outlined by Shoemaker. Williams argues that the less radical, basic case (Perry 104) does not amount to a body transfer, and concludes that, even in the superficial case, if Robinson's body were the recipient of Brown's memories, the resultant person would be Robinson. I will argue that the basic case does not imply the superficial case, that Williams's arguments for correct anticipation do not imply personal identity, and that a suitable causal connection between the apparent memories of Brownson and the experiences of Brown's past life obtains in the superficial case but not in the basic case; the person with Brown's brain actually has Brown's memories. Hopefully these considerations will discover flaws in any superficial bodily theory of personal identity, vindicate the Brownson case of Williams's objections, and thereby allow for the possibility of superficial body transfer.

The Basic Case vs. The Superficial Case

Suggesting that personal identity does not imply bodily identity, Shoemaker presents a case of putative body transfer in support of a memory theory of personal identity. In Shoemaker's example, Brown's brain is surgically removed from Brown's body and placed into Robinson's empty cranium. Shoemaker calls the amalgamation of Robinson's body and Brown's brain 'Brownson,' and goes on to say that, upon hearing Brownson's claims to be Brown, and Brownson's detailed reports of Brown's past life, we find it difficult not to conclude that Brownson is Brown; that the person with Robinson's body and Brown's brain is Brown (Shoemaker 78). In considering the possibility of such a body transfer, Williams reiterates Shoemaker's intuitions:

[if when] confronted with what was previously A's body, we are prepared seriously to say that we are now confronted with B… it would seem a necessary condition of so doing that the utterances coming from that body be taken as genuinely expressive of memories of B's past. (Williams 180)

Rather than transposing the brains of A and B as a sufficient condition for obtaining "utterances… genuinely expressive of memories of" B's past life issuing from A's body, Williams describes a process in which a brain scan device extracts the memories from a brain, stores the memories in the device, then writes the memories into either the same brain or another. Williams considers this basic case to be a simplification of the superficial case because it satisfies the memory-transfer criterion without positing a brain transfer (Williams 180).

Going beyond the superficial case, Williams introduces a twist in the basic case: Two persons, A and B, have their memories extracted and written to each other's brains via the brain scan device, and the resultant persons are called the "A-body-person" and the "B-body-person" (Williams 181). Before the procedure, A and B are told that

one of the two resultant persons… is going after the experiment to be given $100,000, while the other is going to be tortured. We then ask A and B to choose which treatment should be dealt out to which of the persons who will emerge from the experiment, the choice is to be made (if it can be) on selfish grounds. (Williams 181)

Williams considers the two complementary choices A and B could make in this situation, and questions whether, for example, A can fear or otherwise correctly anticipate the torture to be endured by the A-body-person, and what this would tell us of the identity of the A-body-person. Iterating through six stages of incremental mental re-imaging – beginning with amnesia and culminating with a complete memory transfer – (Williams 190), Williams argues that "no amount of change in my character or my beliefs would seem to affect substantially the nastiness of tortures applied to me" (Williams 188), implying that after the procedure, the A-body-person would be A, and likewise, the B-body-person would be B; Williams concludes that the basic case does not amount to body transfer.

The Presupposition Problem

Williams presents the basic case as a simplification of the superficial case, assumes that the superficial case implies the basic case, and argues that the basic case does not amount to body transfer. If the superficial case implies the basic case, and Williams's arguments succeed in precluding body transfer in the basic case, it follows that body transfer in the superficial case is impossible. However, these arguments against putative body transfer fail because it does not follow from William's argument that the superficial case implies the basic case with respect to transfer of apparent memories that the superficial case implies the basic case with respect to transfer of actual memories, personal identity, etc.

In Williams's first example of the basic case, where a single brain has its memories extracted, stored, and subsequently written back, Williams argues that we cannot but conclude that the resultant man has "the memories he had before the operation" (Williams 180). This example begins to hint of circularity because it seems that, in the basic case, Williams must either presuppose a bodily theory of personal identity or face an even greater, ontological dilemma. We ask Williams, "in the case involving the scanning and immediate write-back of memories to the same brain, whose brain is having memories written to it?" Either there is some person receiving the memories or there is no person receiving the memories. If Williams chooses the former, he must say whether it is a new person who receives the memories, or it is the same person who was scanned.

Correct Anticipation Without Personal Identity

Williams's arguments for correct anticipation do not imply personal identity in the basic case, and therefore cannot be said to refute the possibility of body transfer if we accept them. Detailing a situation in which A and B are forced to choose, of the persons resulting from the memory transposition in the basic case, who will be rewarded with $100,000 and who will be tortured, Williams argues that A could correctly anticipate the pain of the A-body-person were the A-body-person to be the one tortured, and that this would amount to personal identity between A and the A-body-person. I think it is reasonable to disallow any arguments that rely on the testimony of persons whose brains have been erased, but I will proceed with an example that I believe captures Williams's notion of correct anticipation without implying personal identity.

Williams holds the view, which seems to be merely a corollary of the bodily theory, that no degree of psychological change can corrupt personal identity: "my undergoing physical pain in the future is not excluded by any psychological state I may be in at the time…no amount of change in my character or my beliefs would seem to affect substantially the nastiness of tortures applied to me… one's fears can extend to future pains no matter what psychological changes precede it" (Williams 188). It seems possible that the brain scan device could completely replace the memories in my brain with those of another person, a consequence of which I qua person could no longer be said to exist, but I qua animal or simple being capable of experiencing pain in the most basic sense persist. And it seems reasonable to fear experiencing future pain as an animal or as a simple being as much as one would fear experiencing future torture as a self-same person. It follows that we can accept William's arguments for correct anticipation without accepting his assumption that no degree of psychological change can corrupt personal identity, and this allows for correct anticipation without personal identity in the basic case.

Actual Memory and Causal Connection

We are inclined to believe that the transfer of a human brain is sufficient for establishing a suitable causal link between the memory claims of Brownson and the experiences of Brown's past life – a link that would justify the conclusion that Brownson actually remembers Brown's experiences. This view is widely held, both by memory theorists and bodily theorists; many memory theorists hold that memories are in the brain, and many bodily theorists hold that personal identity consists in brain identity. Using the conventional notion of actual memory as apparent memory with a suitable causal link to the event remembered, where by 'suitable causal link' we mean that the events featured in the apparent memory are the proximate causes of the token memory, it seems clear that Brownson has the actual memories of Brown. After all, what causes other than those of the memories in Brown could we posit as the causes of Brownson's apparent memories? The surgical procedure is generic, no part of it involving causation of particular apparent memories other than perhaps those memories involving the procedure itself. There is no brain scan device, only scalpels, sponges, sutures and saws.

Williams resists the view that the superficial case amounts to body transfer, but he seems to agree (Williams 180) that Brownson has actual memories of Brown's past life. It follows from this that Williams would allow Robinson to have Brown's actual memories, and this is quite strange. Our conclusion that Brownson has actual memories of Brown's past life discovers absurdities in William's arguments and suggests that body transfer occurs in the superficial case.

Conclusion

Williams resists the view that Shoemaker's superficial case of memory transfer via brain transposition amounts to body transfer. After arguing that Williams's basic case does not imply the superficial case, that Williams's arguments for correct anticipation do not imply personal identity, and that Brownson has Brown's actual memories in the superficial case, I hope that we understand Williams's superficial bodily theory of personal identity and the objections it raises against the possibility of body transfer, and why we should not accept them.