Brainy Brownson & the Body of Brown: The Reduction of Psychological Identity to

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1 1 Brainy Brownson & the Body of Brown: The Reduction of Psychological Identity to Bodily Identity Abstract: Psychological accounts of personal identity have typically taken the psychological aspects of a person to be irreducible to the person s body. This is justified by an appeal to the plausibility of certain thought experiments concerning the idea of brain transplant and brain transfer, especially Shoemaker s Brownson case. In this paper I argue against the convincing nature of these thought experiments, on the basis of their inability to remain plausible within a materialist account of mind, and that the psychological identity is thus reducible to bodily identity. The proper aim of metaphysical theories is to do justice to, and provide an account of, prephilosophical convictions we have about the world around us. We are quite ready to believe, for example, that generally speaking, the people we meet one day are the very same people when we meet them later on, in a way that is deeper and more substantial than simply sharing some passing resemblance to the earlier set of people. They act and respond to situations and carry out their actions in ways which are, at least as a whole, idiosyncratic; we develop particular notions of someone s personality, this bundled set of features of psychology and character that quite positively give evidence that someone is acting like his or her self. That is to say, it seems fairly clear at the outset that there is something about the psychology of persons that makes him or her who they are, and that it is at least a powerful way of picking out that one person over various times and places. Some, such as, Perry, Shoemaker, and Parfit, have attempted to do justice to this special place of the psychological by offering an account of personal identity that places psychological connectedness at the forefront of what it means to be the same person over time 1. 1 See Derek Parfit, Personal Identity in Metaphysics: Contemporary Readings, ed. Micahel J. Loux (London & New York: Routledge) 375, John Perry, Can the Self Divide? The Journal of Philosophy 69 (1972) 463, and Sydney Shoemaker, Personal Identity: A Materialist's Account, in Shoemaker and Swinburne, Personal Identity, (Oxford: Blackwell)

2 2 However, another aim of a metaphysical theory is to give an account of just what are the most basic features of the world. If something is the case in virtue of something more basic, we should account for that more basic thing as the ground upon which the more obvious stands. If we already have theories as to what the basic nature of reality is, we should also attempt to be consistent therewith, when we begin working out other theories. It is just this situation which we find when we look to psychological theories of personal identity; because, we generally believe that all events that occur within the world are physical events, and that all objects within the world are material objects. Sydney Shoemaker is the only philosopher of which I am aware that has explicitly attempted to maintain such materialist credentials in his account of psychological identity. In his formulation of such a theory, he affirms that his account is fully amenable to such materialist convictions. But in so doing, he still affirms that psychological identity is the best way to account for personal identity; that is to say, that the psychological makeup of a person is irreducible to any other contingent factor of a person, particularly with regard to the person s body. Various thought experiments have been offered so as to argue for this point. In this paper I will argue that his contention fails, and that psychological identity accounts fail to simultaneously do justice to the two convictions previously mentioned. The result is a dilemma: either these psychological accounts must become indistinguishable from bodily continuity, or our materialist convictions regarding minds as things in the world must be given up in order for the theory to work. Specifically, I will attempt to offer a provisional analysis of just what a body is, which has hitherto been appealed to frequently, but otherwise undefined, within the debate on personal identity.

3 3 I. The Appeal of Psychological Identity Shoemaker argues for his account of personal identity by appeal to the conceivability of various kinds of mental transfer. Take, for example, his case of Brownson, the chimerical product of inserting Brown s brain into Robinson s body. Brownson acts, thinks like, and remembers himself, as Brown. But, he is in Robinson s body. We would be well inclined to say, Brown is now in Robinson s body, that the person we call Brown is now animating and directing the body of who was formerly Robinson. If we were more inclined to say, Robinson is now acting like and calling himself Brown, ever since he got Brown s brain put in him, it seems this consideration would play out differently 2. The aim here is to draw out our prephilsophical conviction that is the personality of the person that truly matters. If Robinson is now acting like and claiming that in fact he is Brown, we would be inclined to take his word for it. It would seem that Brown has successfully switched bodies! That Brown is now in Robinson s body, and that Brown s body is not doing very much at all, would thus indicate that the person of Brown has moved through the world without his body. Bodily continuity, then, does not need to obtain for there to be preservation of a person. Similar to the previous thought experiment is the appeal to the brain-state transfer device (henceforth BST), used by a society to swap out their otherwise short lived bodies, moving themselves from a damaged body (in Shoemaker s thought experiment, by radiation) to a fresh (undamaged) one on a regular basis. The society itself considers the copy that is made from the old body to the new one a continuing instance of the very same person; that is, these are not clones, but the same person, bouncing 2 Sydney Shoemaker, Personal Identity: A Materialist's Account, in Shoemaker and Swinburne, Personal Identity, (Oxford: Blackwell)., 78

4 4 about from body to body. Identity has been maintained, and the person walking into the procedure involving the BST is the same one walking out, new body or no 3. In light of such cases, that Shoemaker accounts for personal identity across time in terms of mental states being properly connected across time 4. II. Challenges to the Thought Experiments One immediate consideration of the Brownson thought experiment calls to mind a chief difficulty with an account based on its conclusions: how is it that Brown s brain is not be considered his body? Surely it is at least a part of his body; and, simply speaking, at least a part of Brown is thus in Brownson. Now let s be clear about what the thought experiment is supposed to imply, in full view of Shoemaker s point. In arguing for a psychological account, Brown s psychological personhood is animating Robinson s body, and because of that, Brownson is psychologically continuous with Brown, and thus is Brown. But if such is the case, what are we to do with the fact that a part of Brown s body is in fact a part of Brownson? This thought experiment, when examined, has it that Brownson is both psychologically and bodily continuous with Brown. Our prima facie judgment that the body doesn t count, if Brownson is Brown, turns out to be misguided. In this instance, it is really indeterminate, as it seems that the use of the term body has been used rather loosely. 3 Ibid., It is in light of such cases that both Parfit and Perry are inclined to develop defenses of psychological accounts. Parfit seems impressed by some of the more esoteric possibilities of brain transplants (Parfit, 375), while Perry seems indebted to a BST type of thought experiment (Perry, 463). As these theorists rest on the plausibility of what Shoemaker has advanced, I will restrict my analysis to Shoemaker s own articulations of the thought experiments, as the difficulties I find in his own accounts apply equally well to Parfit and Perry s.

5 5 It is not quite so clear-cut in the case, however, of the BST. For it seems there in fact is nothing of the body that remains in the movement of mental states from one body to another. If there had been, the point would have been missed. But another question arises. Shoemaker affirms materialism, and thus charges that in such cases as the BST actually moving a person from one body to another, only physical events have occurred. His appeal to the transfer of information is nebulous. If what is going on is the transfer of entities that are established by means of their place within a system of causes and realizations, then we must consider how the transfer from one such system to another is to be accomplished. Shoemaker s account thus inspires two questions that require further elaboration and consideration: what is meant by the body, and what part does it play in the Brownson case; and what sort of physical events are taking place in the context of a BST managing to be person-preserving. I will address these questions in turn. III. Brainy Brownson and the Body of Brown The initial appeal of Shoemaker s Brownson thought experiment rests in a sort of prima facie holism with regards to bodily identity. That is, it seems at best arbitrary to claim that only some particular amount of one s body needs be continuous in order to maintain continuity. It seems that a person can have some small section of his or her brain moved into another mostly complete body would still appear to have left his or her body behind, assuming the brain transplant was successful and person preserving. But all the while it still appears some mistake has been made when we say that Brownson is not bodily continuous with Brown, since some measurable amount of Brownson is in fact bodily continuous with Brown.

6 6 One might simply say that this is a weakness with respect to the thought experiment, but it is all the same revealing. It is fairly clear that Shoemaker is appealing to some readily understood concept the body, and thus makes no attempt to get at what he means thereby. But when we look to the particulars it seems that we render the thought experiment indecisive. As was noted above, we end up with a good reason to affirm psychological continuity only if we deny that Brownson having Brown s brain is any sort of bodily continuity. But this seems indefensible. We need to make clear exactly what is meant by the body to clear up this ambiguity. In looking to various other positions Shoemaker wishes to maintain, we might be thus well guided in establishing a concept of the body that would be charitable to his project. Specifically, I consider his affirmation of a functionalist construal of mind to be of relevant consideration. IV. Advancing a Definition of Body The body, first and foremost, is a physical object, in and amongst a world of similar physical objects. It both causes and experiences effects that occur in the world, which makes it the bearer of a particular set of properties. In the case of persons with bodies, we affirm the fact that there are mental events such to the effect of bearing a particular kind of consistency across time; this is the whole thesis of psychological continuity. Now, it being the case that mental events are properties 5 there is thus some sort of proper analysis of how these properties come to be the properties of a physical object that we consider to be a body. 5 My thanks to Richard Swinburne for reminding me of this, in private conversation.

7 7 Enter functionalism. In Shoemaker s offered construal, mental events are what they are in virtue of their causes, and for the effects that they bring about. These effects consist in physical events in the case of a materialist construal such as Shoemaker s, insofar as they are realized in physical objects. All of these causes and effects occur in the context of a complex system 6. So we have the start of a concept there already: a body is the physical object in which a complex system of mental events (henceforth a functional system) is realized in. But this is insufficient. We require some way of delimiting the bounds of a body. The very thing that makes the case so appealing for psychological continuity is that we find very powerful evidence for a person being the same across time in their consistency of psychological propensities and characteristics; and as these are mental events, they must be realized in a physical object, a body. And so a concept of the body might find its delimitation there: a body is the physical object wherein a functional system is realized, and in doing so maintains psychological continuity. In the case of Brownson, assuming he really is Brown in Robinson s body (as Shoemaker would have us understand the situation), we have the case of a very small part of Brown in Robinson. But is that the same as his body? We might escape the prima facie holism that first made the thought experiment convincing, however, by asserting that Brown s body, any person s body, really, is in fact the minimal amount of physical matter necessary to realize the functional system that produces effects that are psychologically continuous with Brown. That is to say, what counts as the essential part of Brown s body is that part that caused him to be psychologically continuous with himself, which is now 6 Shoemaker., 92-97

8 8 inhabiting the physical object that used to be Robinson. Presumably, if another bit of Brown had been transplanted, an arm, a kidney, etc., he would remain where he was, and Robinson where he was. If this is the case, however, then the thought experiment remains inconclusive, as Brownson is both bodily continuous and psychologically continuous with Brown. V. Individuation and Functional Systems: Considering the BST Thought Experiment It is quite obvious that the above considerations have no effect on Shoemaker s other thought experiment, the BST, as there is in fact no instance of bodily continuity. No brains, no heads, no other organs at any point cross from one physical instantiation of the person to the other. It seems here that the essence of identity is in fact purely psychological. In one way or another, the mental events that make up a person s psychology have in fact crossed over into a completely new body. As was noted above, however, it remains to be seen whether we can make sense of this notion an actually person-preserving BST whilst affirming a strictly materialist framework. Shoemaker girds up his materialism with his appeal to functionalism, as was noted above. In the case of the BST, at every point in time the mental events that make up a person s psychology are realized in physical objects. Therefore, he makes no appeal to the immaterial. The problem with this account occurs when we consider what is ostensibly happening to these mental events in their various realizations. The mental event is what it is in the context of a particular system. In this case of conscious beings, we think of these

9 9 systems as minds. Now, what Shoemaker seems to miss is how it is possible for these mental events to jump from one system to another, whilst remaining actually continuous. If they continue to exist by virtue of what they are in a system, then it is only within the confines of remaining within that system of causes and effects that they continue to be the same. If the BST is person-preserving, then the shift from one body to the device, and then to a new body, would all have to occur within the same system. Indeed, Shoemaker seems to be claiming just this. But recall again how these systems are, in conscious beings, that which we call minds. If the BST accomplishes its person-preservation in a purely material fashion, then there is no delimitation of the mind with respect to where the body begins and ends (this is what Shoemaker has been trying to affirm all along). But this would seem to entail that mental states of one particular person can be ushered along and realized in just whatever set of matter is available to it, so long as it is something capable of realizing these mental states, and that these moves occur by virtue of whatever undiscovered physical means that the BST is based upon. The delimitation of the mind is, in fact, then identical with the confines of the physical world, or at least the entire collection of physical objects capable of realizing mental states. And again, Shoemaker appears comfortable with this. But is this free of unintended consequences? The problem then seems to be, how on earth are we to distinguish one mind from another? The entire aim of providing an account of personal identity seems to be to establish how the preservation of one person across time is accomplished. A key component of what it means to be a particular person is individuation, that the person is themself and no one else. A fairly obvious component of individuation is that it is this person at place 1 and time 1, and no one else. A purely

10 10 materialist account that does not delimit the scope of a where minds can and cannot be realized in sets no limits on individuation. This seems to entail a bizarre sort of monism that I do not think Shoemaker wishes to affirm. Why is this a problem? If we dispense with individuation we come up against the very real issue of minds becoming indiscernible. Consider the case of Brown wishing to become Brownson. He lives in a world wherein a BST has been developed, and thus moves all of his mental states into Robinson s body. But in doing so, we have, instead of some strange chimeric object, simply the inability to distinguish Brown from Robinson. Robinson is now psychologically continuous with Brown insofar as the very same set of physical objects realize both Robinson s mental states and Brown s mental states. All physical states true of Robinson are now true of Brown. By Leibniz s Law, wherein two objects with identical properties are indistinguishable from one another, Brown now is Robinson, and Robinson is Brown. Person-preserving psychological continuity has not been maintained, by virtue of the fact that the person itself has suddenly ceased to be individuated from something that it is not. If we were to countenance this, a very severe adjustment to our common sense notions of individual persons, or individual minds, would be in order. It seems as though person-preserving jumps are intelligible, but only insofar as the account in which they take place does not require any and all events to be purely physical. There seems to be no material ether in which mental events might be materialized in the space between bodies. So, in order to maintain his psychological account, on the basis of the BST thought experiment, he must give up his materialism, or the thought experiment itself. If the former, all holds with regards to psychological

11 11 continuity, but then we are left with having to account for just what a person, much less his or her mind, consists of, and what it is that animates the bodies we obviously have. If the latter, we are left with no good reason to dispense with bodily continuity! Therefore, the two positions are mutually exclusive, in Shoemaker s rendering; and, with these considerations, we have no clear reason to affirm the psychological identity theorists claim that the psychological is somehow irreducible to the body. VI. Conclusion It is important to note that, in analyzing psychological continuity by means of bodily continuity, and thereby reducing the former to the latter, we have done no disservice to our prephilosophical convictions about personalities and psychology. All features of this facet of persons remain intact, so long as the functional system continues to be the same. This function system, of course, is realized by the body, and it is to this body that we predicate identity over time. But since the features of the body s interaction with the world, that is, the idiosyncratic ways effects are realized in the world, are the very thing that remain identical, the psychological features that are so realized remain, and thus derive their continuity from the body s own continuity. We thus are able to maintain both our psychologistic and materialistic convictions about the world around us, by so affirming that it is the person s body that matters in our theories of personal identity. Bibliography Parfit, Derek, Personal Identity in Metaphysics: Contemporary Readings, ed. Micahel J. Loux London & New York: Routledge (2001)

12 12 Perry, John Can the Self Divide? The Journal of Philosophy 69 (1972) Shoemaker, Sydney Personal Identity: A Materialist's Account, in Shoemaker and Swinburne, Personal Identity, Oxford: Blackwell (1984)