Personal Identity
Perry (John), Ed.
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Amazon Book Description

  1. This volume brings together the vital contributions of distinguished past and contemporary philosophers to the important topic of personal identity. The essays range from John Locke's classic seventeenth-century attempt to analyze personal identity in terms of memory, to twentieth-century defenses and criticisms of the Lockean view by Anthony Quinton, H.P. Grice, Sydney Shoemaker, David Hume, Joseph Butler, Thomas Reid, and Bernard Williams.
  2. New to the second edition1 are Shoemaker's seminal essay "Persons and Their Pasts", selections from the important and previously unpublished Clark-Collins correspondence, and a new paper by Perry discussing Williams.

Amazon Customer Review2
  1. This is a first-rate anthology on personal identity that includes important historical work and recent (up to the 70s) discussions of the relevant issues. It begins with an informative introduction by Perry. The introduction presents the basic problem and the way philosophers traditionally have thought about it. Then Perry gives a summary of most important points made in the historical material included in the anthology.
  2. What is the question of personal identity? Basically, it's the question of what makes a person one and the same person through time. I assume I'm the very same person I was two days ago, two months ago, two years ago, two decades ago, etc. Given that I've changed a great deal over that period of time, how could this be? It seems like I, the very person sitting here and typing this now, was once an undergraduate planning to go to grad school, once a high school student getting ready for college, once an elementary school kid, and once a new-born baby. But it's clear that I don't look or think a lot like those previous people who appear to be one and the same as I am. There's been a lot of physical and psychological change over time, and yet I think I'm the very same person I was at those various times. How could that be?
  3. And this is a philosophical issue that seems to have practical ramifications. It appears to have consequences for how we understand ourselves and other people: Does a person survive radical amnesia? How about brain death3? Could a person survive after bodily death? Could there be multiple people in the same body at the same time? If a person's memories, beliefs, desires, etc. change so that there's little or no connection to her previous self, is she really the same person at all anymore? Consequences for how we relate to people: If my friend suffers from amnesia and never recovers his prior memories, is he really still my friend (is he still the same person I knew before)? If my mother is dying from a disease that has left her little more than a body rotting away in a hospital bed, is she still really my mother (i.e. the same person who raised me)? And moral consequences: Is a fetus4 a person? If a person's psychology has radically changed over time, is it still fair to hold her responsible for things she did long ago (maybe she's no longer the person who did whatever we want to hold her responsible for)?
  4. Now, clearly, it's pointless to try to summarize even the most important ideas that you'll find in the readings collected here. There are too many positions, too many important arguments, and too many interesting issues to say much of importance about the anthology as a whole. But I will try to give you some sense of the contents here.
  5. The first reading is from the seminal work on this topic, namely Locke's discussion in his Essay concerning Human Understanding. In a few justly famous thought experiments5, Locke argues against the view that personal identity consists in identity of immaterial soul over time and the view that it consists in identity of body over time. He then proposes a version of the view that personal identity consists in the stages of a person sharing memories of previous stages. This is followed by more recent essays by Paul Grice and Anthony Quinton in which they defend views similar to Locke's. These two essays are responses to problems raised in the next two essays, both of which include classic objections to Locke's memory theory of personal identity. Joseph Butler argues that Locke's view begs the question since any accurate account of memories presupposes an account of personal identity. Thomas Reid argues that Locke's view fails to respect the transitivity of identity in some cases. And then there are two more readings querying the plausibility of the memory view, one by Sydney Shoemaker and one by Perry himself.
  6. Then the anthology moves on from discussions of the memory view to other views about personal identity. The first alternate view is Hume's. In some famous material from his Treatise of Human Nature, he argues that there is no personal identity over time. Two of the remaining three papers argue for similar conclusions. Derek Parfit6 argues both that there may be no personal identity over time, and that identity isn't what matters7 through time. It is perfectly rational, he thinks, to care about the future of beings with psychologies similar to ours even if we aren't identical to them; and this is supposed to have important practical consequences. Thomas Nagel argues that our concept of a person may not apply in certain real-world cases of brain bisection, and he thinks that such cases may show that our concept of a person doesn't even apply to us in our normal condition. The final paper in the collection is by Bernard Williams. He argues that there seem to be cases in which bodily continuity is more important than psychological continuity8.
  7. While the reader should look elsewhere for the state of the art on the issues, I'd recommend this anthology to anyone interested in personal identity. Nearly all of these papers are classics that you ought to know if you're going to more recent work on this issue, and so it's still well worth buying even if you're more interested in contemporary thought about the topic.

In-Page Footnotes ("Perry (John), Ed. - Personal Identity")

Footnote 1: Footnote 2: Of the First Edition.


University of California Press, 1975

"Butler (Joseph) - Of Personal Identity"

Source: Perry - Personal Identity

"Grice (H. Paul) - Personal Identity"

Source: Perry - Personal Identity

Philosophers Index Abstract
    In this article, the author discusses the nature of the main question philosophers ask when concerned with the problem of a personal identity. Then, the question is asked whether it is possible to maintain a pure ego theory of the self. Finally, the author attempts to defend a form of the logical construction theory. (Staff)

"Hume (David) - Our Idea Of Identity"

Source: Perry - Personal Identity
COMMENT: Part of "Of Skepticism With Regard to the Senses", Treatise I.IV.II

"Hume (David) - Second Thoughts (on Personal Identity)"

Source: Perry - Personal Identity
COMMENT: Treatise III Appendix

"Hume (David) - Treatise I.IV.VI: Of Personal Identity"

Source: Hume - Treatise I.IV.VI; also in Perry - Personal Identity

"Locke (John) - Of Identity and Diversity"

Source: Locke - Essay, Book 2, Chapter 27
Write-up Note1 (Full Text reproduced below).

For an essay on this chapter Click here for Note.


Write-up2 (as at 14/11/2019 19:43:41): Locke on Personal Identity

What, if anything, is wrong with Locke’s account of personal identity?
  • Locke’s account of personal identity appears in Book II, Chapter 27 of his Essay ("Locke (John) - Of Identity and Diversity"). To address the question before us, we need first of all to discuss what Locke understands by persons.
  • For Locke, a person is characterised by rationality and consciousness – a person is a "thinking intelligent being" that can consider itself the same thinking thing across different times and places (§9:335.10-13). Additionally, personhood is a forensic concept: a person is something that can be praised or blamed, and which is legally responsible (§26:346.26-28). Locke considers it of first importance that the divine justice at the resurrection should fix on the right person (§26:347.9).

Personal Identity
  • Personal identity is determined by the scope of consciousness of self (§9:335.24-26).
  • A self is that present thinking and perceiving thing with its history of memories. I am identical with the self I was in the past if I can remember my thoughts and actions from that time (§9:335.25-28).
  • "Noonan (Harold) - Locke" (pp.43-44) points out that “Consciousness” in Locke’s day meant shared knowledge, in particular that had by a present self of a past self’s thoughts & actions. For Locke, it consists in present perceptions, sensations, thoughts and memories of the past (§9:335.13-18). It is consciousness that unites “existences and actions” over time into the same person – “whatever has the consciousness of present and past actions, is the same person to whom they both belong” (§16:340.33-35).
  • The identity conditions for persons must not be confused with those for human beings, which are no different to those for other living organisms, such as horses; namely the “participation of the same continued life, by constantly fleeting particles of matter, in succession vitally united to the same organised body” (§6:331.35-332.2).
  • In contrast, the identity of pieces of inanimate matter arises purely from the atoms that make them up (§3:330.18-20).
  • An immediate consequence of Locke’s definition of personhood is the distinction between person and man (human being). Locke imagines the exchange of consciousnesses of a prince and a cobbler (§15:340.10-18). Locke says that the cobbler animated by the prince's consciousness is the same person as the prince, because personhood follows consciousness. However, the cobbler with the prince’s consciousness is still the same man as the cobbler, because "being a man" depends more on corporeal than psychological attributes, as Locke explains in his discussion of the rational parrot, which, despite its accomplishments, remains a parrot (§8:333.5-12).
  • "Noonan (Harold) - Locke" (p.27) summarises Locke’s reasons for making personal identity a matter of sameness of consciousness: they fit the three aims behind his account of personal identity.
    1. Firstly, he wants an account that’s neutral between dualists and materialists, but allows for immortality and the resurrection.
    2. Secondly, we can’t be sure about the identity of substance, but we can about consciousness, so this repels sceptical doubts.
    3. Thirdly, consciousness reflects our practical concern for our identity; I have no reason to care about substantial identity, except where I own and am conscious of that substance’s actions and memories (§14:339.15-340.2).
    As "Jolley (Nicholas) - Personal Identity" (p.101) points out, certain well-meaning modifications to Locke’s theory will be ruled out by his need to accommodate personal immortality and divine justice.

Substance and Personal Identity
  • According to any straightforward reading of the text, Locke denies the relevance of substance to the issue of personal identity. For Locke, there are three kinds of substance:
    1. God,
    2. “Finite intelligences” (souls or spiritual beings) and
    3. Bodies (§2:329.1-2).
  • So, for personal identity to be substantial, it would need to reside either in the soul or in the body. By means of thought experiments, Locke excludes both:
  • The body because:
    1. The body at the resurrection differs from the earthly body, so if the person were the body, the resurrected person would not be the same as the person that died (§15.340.5-6).
    2. A corpse would be a person (§23:344.16).
    3. Locke can imagine two persons inhabiting the same body, the one by day, the other by night, as "incommunicable consciousnesses" (§23:344.18-20).
    4. He can also imagine a single person serially occupying two bodies as though changing clothes (§23:344.24-25).
  • The soul because:
    1. A person could undergo change of spiritual substance, if his present soul remembers the thoughts and experiences of his past soul (§13:338.22-27).
    2. A single spiritual substance could serve as the soul for two distinct persons, if my soul should forget the thoughts and experiences it had when it was the soul of another person (§14).
  • Nevertheless, while God could have “superadded” the power of consciousness to matter (IV.3§6:541.3), Locke thinks that it’s most likely that human beings do have souls (§25:345.25-27) and that it’s our souls that think “in” us (§10:336.13).

Problems with Locke’s Account of Personal Identity
  1. Priority
    • I’m the same person today as I was yesterday because I remember the thoughts, experiences and deeds of my earlier self. However, don’t I also remember other people’s thoughts and deeds? Locke might respond by claiming that I remember my own experiences in a first-person way, but others’ only in a third-person way.
    • Initially, this response appears circular, since the reference to “first-person” memories mentions “person”, and it seems that I need to grasp what constitutes the difference between myself and another person in order to recognise first-person memories.
    • "Lowe (E.J.) - Locke: Identity" (p.110) suggests that the first / third person distinction needed here is no more than the distinction between remembering from the perspective of one involved and one not, without presuming that the one involved was myself. One can then deny that, even in principle, one could have first-person memories of the experiences of another person since, having been involved, I would identify myself with such a person.
    • "Lowe (E.J.) - Locke: Identity" (p.117) thinks a genuine circularity arises if Locke thinks of human persons as highly complex modes or properties of spiritual substances, these properties being complex patterns of successive and interrelated states of consciousness. This is because Locke specifies the identity conditions of persons in terms of relations between conscious mental states, but fails to appreciate that those conscious mental states depend for their identity on the identity of the persons whose states they are. This dooms Locke’s strategy to circularity. "Lowe (E.J.) - Locke: Identity" (p.117) concludes that conscious states are individuated by persons, and not vice versa.
  2. Memory
    • "Ayers (Michael R.) - Contemporary Reactions to Locke's Theory" (p.271) points out that Locke doesn’t suppose that there are a lot more persons than men at the resurrection, or that many crimes will go unpunished. So, people will have to have their memories restored. But, this presupposes a set of actions that are theirs whether or not they remember them, and, on Locke’s account, again leads to circularity.
    • "Winkler (Kenneth) - Locke on Personal Identity" (p.168) considers the problem of transference (cf. §13:338.17) whereby God at the resurrection transfers to my resurrected consciousness some acts that weren’t mine but which I’m now willing to own and be punished for, despite the fact that I didn’t perform them. Locke thinks God wouldn’t allow this situation, but to what can he appeal if Locke’s right about what constitutes a person? While no ancestor-self acknowledged these acts, my present self does. "Jolley (Nicholas) - Personal Identity" (p.117) suggests that God can sort things out at the resurrection by checking for inconsistencies. "Winkler (Kenneth) - Locke on Personal Identity" (p.171) and other writers suggest that Locke might escape by saying that while memory might be necessary for personal identity, it is not sufficient, and that personal identity consists in something underlying consciousness.
    • "Jolley (Nicholas) - Personal Identity" (p.113) also considers the problem of pseudo-remembering. Genuine remembering is causal, running though one and the same body. So, either Locke’s theory collapses into bodily identity or is wildly implausible, claiming that George IV was the same person as led the troops at Waterloo because he (falsely) remembered so doing. These considerations seem fatal to Locke’s account, with mounting suggestions that a substantial account of personhood is required.
  3. Amnesia
    • Isn’t one still responsible for actions one has committed but forgotten? While Locke admits that the same man is responsible, his forensic understanding of personhood means that punishment properly belongs to the person, not the man.
    • "Winkler (Kenneth) - Locke on Personal Identity" (p.153) argues that, for Locke, the self has to appropriate things to itself. Since the self is constituted by what it takes to be included in it, actions and thoughts forgotten beyond recall cannot be part of it. On Locke’s account one has only done what one is conscious of having done. "Ayers (Michael R.) - Contemporary Reactions to Locke's Theory" (p.266) wonders whether reward and punishment even make sense unless the recipient acknowledges the action in question as his own.
    • When we punish someone even though he cannot remember what he did, this, according to Locke, is like punishing the wrong twin (§19:342.19-20). We don’t punish the sane man for what he did when out of his mind (§20:342.35-343.4). Locke would not punish the sobered-up drunkard for his now-forgotten actions, but claims that human law has to operate as it does, since we cannot know whether a man is counterfeit or not in claiming amnesia. Locke’s reasoning is based on our necessary ignorance of other people’s mental states, but he hopes that any injustices will be put right on the day of judgement (§22:343.34-344.12).
    • Locke is right to allow that the genuinely insane man is a different person during the period of his insanity, but amnesia has nothing to do with it. We would still forgive the recovered insane man, and treat him as having been a different person, even were he to remember the period of his insanity.
    • We don't do this for amnesiac drunkards; not because of the greater likelihood of dissimulation, but because the drunkard knew what he would be likely to do when he got drunk. Drunkenness is a voluntarily contracted state, indeed a crime, and no crime can excuse another. So, the sobered-up drunkard deserves punishment whatever his memory of his actions might be. In contrast to the recovered madman, on being informed of his behaviour he ought to own these acts.
    • Hence, Locke’s theory of personal identity fails to explain or derive plausibility from moral and legal accountability.
  4. Transitivity
    • Identity is a transitive relation. So, if A is the same person as B and B is the same person as C, then A must be the same person as C. However, as Thomas Reid pointed out, this isn’t the case on Locke’s account. Imagine a small boy caught stealing apples, growing up into a young officer and declining into an old general. The old general remembers being a young officer and the young officer remembers being a mischievous boy, but the old general doesn't remember being the mischievous boy. According to Locke, the three cannot be the same person, though two pairs are.
    • We can rescue Locke by replacing the relation of first-person memory by the ancestral of that relation, which is always guaranteed to be transitive. For x to stand in the ancestral of the memory relation to y, it suffices for x to remember the deeds of a who remembers the deeds of b … who remembers the deeds of y. With this adjustment, Locke could justifiably claim that the old general is the same person as the boy.
    • "Lowe (E.J.) - Locke: Identity" (p.113) thinks that Locke wouldn’t be happy with this solution because he thinks of personhood as a forensic concept. A person should not be held responsible and punished for deeds he didn’t do which, for Locke, are those he can’t remember committing. However, "Winkler (Kenneth) - Locke on Personal Identity" (p.170) thinks that the young officer has appropriated the acts of the young boy, and because the old general has identified himself with the young officer, he has thereby appropriated all the acts he has appropriated. Because, on Lowe’s account, the self accumulates over time, rather than being constituted by instantaneous consciousness, identity of the self remains transitive.
  5. Substances
    • Locke thinks we have no clear idea of substance (I.4§18:95.29-33), so we certainly have no clear idea of when something is the same substance. Consequently, we need a nonsubstantial notion of a thing, and we do have a clear idea of the same self, considered as self.
    • As "Lowe (E.J.) - Locke: Identity" (p.107) points out, by Locke’s own definition, souls are themselves persons, since they are thinking, self-conscious beings. Yet, my soul isn’t the same person as me, because I could get a new one. There appear to be two kinds of person, things like my soul and things like me, with different criteria of identity. However, a sortal term, like “person”, can have associated with it only one criterion of identity, which enables us to count them.
    • The problem is compounded by Locke’s concerns for “sensible creatures”, to whom memories are transferred, which (as both "Ayers (Michael R.) - Contemporary Reactions to Locke's Theory" (p.264) and "Noonan (Harold) - Locke" (p.45) point out) are thinking substances, not persons (§13.338.14-18). Locke worries that a soul will be wrongly punished or rewarded at the resurrection by having some consciousness passed on to it for which it wasn’t originally responsible. The wrong thinking substance will suffer, even though the right person (consisting in more than one thinking substance) is punished. It was once thought fitting that the same matter be punished as performed the deed, so Locke may be being ironical, as though souls have their feelings too.
    • "Lowe (E.J.) - Locke: Identity" (p.117) thinks that to resolve such difficulties, we must equate persons with thinking substances. This doesn’t commit us to belief in “immaterial souls” if, contra Descartes, we allow matter to have attributes of thought as well as extension. However, given Locke’s explicit arguments against persons being souls, this suggestion is not to be preferred.
    • "Lowe (E.J.) - Locke: Identity" (p.73), "Bennett (Jonathan) - Locke's Philosophy of the Mind" (p.106) and "Noonan (Harold) - Locke" (p.30) are in agreement that Locke distinguishes between basic substances (atoms) and non-basic substances (trees), the latter being modes of the former. In this chapter, Locke doesn’t use “substance” for “thing”, but for fundamental constituents of reality.
    • This makes way for "Winkler (Kenneth) - Locke on Personal Identity"’s (p.164) interesting neo-Lockean proposal, for which we must consider substance-stages, temporal slices of Lockean non-basic substances, which persons supervene3 on (or are constructed out of). Successive stages are connected by two relations – that of psychological continuity, which connects them into persons, and physical continuity, which connects them into living things.
    • Ontologically, persons and living things are then on the same level, but may share only some of their stages. Locke’s insistence that identity of persons is not determined by identity of substance means only that the identity isn’t determined by either of two kinds of substances in particular – organised bodies or immaterial souls.
  • While Locke has escaped the transitivity objection, the problems raised by amnesia make Locke’s account implausible. Additionally, he is convicted of circularity on two counts above (See under Priority and Memory). Consequently, Locke has to give up all thought of consciousness defining personal identity, though it is certainly relevant. Locke was right to consider the concept of a person as fundamentally a psychological one, involving mental powers including rationality and self-consciousness.
  • So, we must reject Locke’s characterisation of persons as insubstantial beings, constituted of streams of consciousness interconnected by memory. Locke ought to have acknowledged that persons are substantial aggregates of Winkler’s substance-stages, of which aggregates their conscious states are modes.

In-Page Footnotes ("Locke (John) - Of Identity and Diversity")

Footnote 2:
  • This is the write-up as it was when this Abstract was last output, with text as at the timestamp indicated (14/11/2019 19:43:41).
  • Link to Latest Write-Up Note.

"Nagel (Thomas) - Brain Bisection and the Unity of Consciousness"

Source: Nagel (Thomas) - Mortal Questions

Introduction (Full Text)
  1. There has been considerable optimism recently, among philosophers and neuroscientists, concerning the prospect for major discoveries about the neurophysiological basis of mind. The support for this optimism has been extremely abstract and general. I wish to present some grounds for pessimism. That type of self-understanding may encounter limits which have not been generally foreseen: the personal, mentalist idea of human beings may resist the sort of coordination with an understanding of humans as physical systems, that would be necessary to yield anything describable as an understanding of the physical basis of mind. I shall not consider what alternatives will be open to us if we should encounter such limits. I shall try to present grounds for believing that the limits may exist - grounds derived from extensive data now available about the interaction between the two halves of the cerebral cortex, and about what happens when they are disconnected. The feature of the mentalist conception of persons which may be recalcitrant to integration with these data is not a trivial or peripheral one, that might easily be abandoned. It is the idea of a single person, a single subject of experience and action, that is in difficulties. The difficulties may be surmountable in ways I have not foreseen. On the other hand, this may be only the first of many dead ends that will emerge as we seek a physiological understanding of the mind.
  2. To seek the physical basis or realization of features of the phenomenal world is in many areas a profitable first line of inquiry, and it is the line encouraged, for the case of mental phenomena, by those who look forward to some variety of empirical reduction1 of mind to brain, through an identity theory, a functionalist theory, or some other device. When physical reductionism2 is attempted for a phenomenal feature of the external world, the results are sometimes very successful, and can be pushed to deeper and deeper levels. If, on the other hand, they are not entirely successful, and certain features of the phenomenal picture remain unexplained by a physical reduction3, then we can set those features aside as purely phenomenal, and postpone our understanding of them to the time when our knowledge of the physical basis of mind and perception will have advanced sufficiently to supply it. (An example of this might be the moon illusion, or other sensory illusions which have no discoverable basis in the objects perceived.) However, if we encounter the same kind of difficulty in exploring the physical basis of the phenomena of the mind itself, we cannot adopt the same line of retreat. That is, if a phenomenal feature of mind is left unaccounted for by the physical theory, we cannot postpone the understanding of it to the time when we study the mind itself - for that is exactly what we are supposed to be doing. To defer to an understanding of the basis of mind which lies beyond the study of the physical realization of certain aspects of it is to admit the irreducibility4 of the mental to the physical. A clearcut version of this admission would be some kind of dualism. But if one is reluctant to take such a route, then it is not clear what one should do about central features of the mentalistic idea of persons which resist assimilation to an understanding of human beings as physical system. It may be true of some of these features that we can neither find an objective basis for them, nor give them up. It may be impossible for us to abandon certain ways of conceiving and representing ourselves, no matter how little support they get from scientific research. This, I suspect, is true of the idea of the unity of a person: an idea whose validity may be called into question with the help of recent discoveries about the functional duality of the cerebral cortex. It will be useful to present those results here in outline.


"Parfit (Derek) - Personal Identity"

Source: Perry - Personal Identity

Philosophers Index Abstract
  1. Some people believe that the identity of a person through time is, in its nature, all-or-nothing. This belief makes them assume that, in the so-called 'problem cases', the question "would it still be me?" must have, both a definite answer, and great importance.
  2. I deny these assumptions. I try to show that the identity of a person through time is only, in its logic, all-or-nothing. In its nature, it is a matter of degree.
  3. I then propose a way of thinking in which this would be recognized.

Author’s Introduction
  1. We can, I think, describe cases in which, though we know the answer to every other question, we have no idea how to answer a question about personal identity. These cases are not covered by the criteria of personal identity that we actually use.
  2. Do they present a problem?
  3. It might be thought that they do not, because they could never occur. I suspect that some of them could. (Some, for instance, might become scientifically possible.) But I shall claim that even if they did they would present no problem.
  4. My targets are two beliefs: one about the nature of personal identity, the other about its importance.
  5. The first is that in these cases the question about identity must have an answer.
  6. No one thinks this about, say, nations or machines. Our criteria for the identity of these do not cover certain cases. No one thinks that in these cases the questions "Is it the same nation?" or "Is it the same machine ?" must have answers.
  7. Some people believe that in this respect they are different. They agree that our criteria of personal identity do not cover certain cases, but they believe that the nature of their own identity through time is, somehow, such as to guarantee that in these cases questions about their identity must have answers. This belief might be expressed as follows: "Whatever happens between now and any future time, either I shall still exist, or I shall not. Any future experience will either be my experience, or it will not."
  8. This first belief – in the special nature of personal identity – has, I think, certain effects. It makes people assume that the principle of self-interest is more rationally compelling than any moral principle. And it makes them more depressed by the thought of aging and of death.
  9. I cannot see how to disprove this first belief. I shall describe a problem case. But this can only make it seem implausible.
  10. Another approach might be this. We might suggest that one cause of the belief is the projection of our emotions. When we imagine ourselves in a problem case, we do feel that the question "Would it be me ?" must have an answer. But what we take to be a bafflement about a further fact may be only the bafflement of our concern.
  11. I shall not pursue this suggestion here. But one cause of our concern is the belief which is my second target. This is that unless the question about identity has an answer, we cannot answer certain important questions (questions about such matters as survival, memory, and responsibility).
  12. Against this second belief my claim will be this. Certain important questions do presuppose a question about personal identity. But they can be freed of this presupposition. And when they are, the question about identity has no importance.

COMMENT: For Notes, see "Funkhouser (Eric) - Notes on Parfit, 'Personal Identity'".

"Perry (John) - Personal Identity, Memory, and the Problem of Circularity"

Source: Perry - Identity, Personal Identity and the Self, 2002, Chapter 5

  1. Grice’s Theory
  2. Circles and Logical Constructions
  3. Three Charges of Circularity
  4. Memory
  5. Logical Constructions and Inferred Entities

COMMENT: Also in "Perry (John), Ed. - Personal Identity"

"Perry (John) - The Problem of Personal Identity"

Source: Perry - Personal Identity

  1. Persons and Puzzles
  2. Persons and Person-Stages: Identity and Unity
  3. Locke’s Theory
  4. Locke, Quinton, and Grice
  5. Locke and Butler on Substance
  6. Hume’s Theory
  7. Concluding Remarks

COMMENT: This is just the Introduction to "Perry (John), Ed. - Personal Identity".

"Perry (John) - Williams on The Self and the Future"

Source: Perry - Identity, Personal Identity and the Self, 2002, Chapter 6

  1. Putative Examples of Body Transfer
  2. The Reduplication Argument1
  3. The Nonduplication Argument


"Quinton (Anthony) - The Soul"

Source: Perry - Personal Identity

Philosophers Index Abstract
  1. This is an argument for the constructability of an empirical concept of the soul, which, like Locke's, interprets the soul as a sequence of mental states logically distinct from the body and is neutral with regard to the problem of the subject.
  2. The soul is defined as a series of mental states connected by continuity of character and memory.
  3. The objection that a memory criterion presupposes a bodily criterion is considered.
  4. Arguments for it are judged forceful but not conclusive.
  5. Finally, the paper deals with the complex question whether a soul can exist in an entirely disembodied1 state.


"Reid (Thomas) - Of Identity"

Source: Perry - Personal Identity

"Reid (Thomas) - Of Mr. Locke's Account of Our Personal Identity"

Source: Perry - Personal Identity

"Shoemaker (Sydney) - Personal Identity and Memory"

Source: Perry - Personal Identity

Author’s Introduction
  1. Persons, unlike other things, make statements about their own pasts, and can be said to know these statements to be true. This fact would be of little importance, as far as the problem of personal identity is concerned, if these statements were always grounded in the ways in which people's statements about the past histories of things other than themselves are grounded. But while our statements about our own pasts are sometimes based on diaries, photographs, fingerprints, and the like, normally they are not. Normally they are based on our own memories, and the way in which one's memory provides one with knowledge concerning one's own past is quite unlike the way in which it provides one with knowledge concerning the past history of another person or thing.
  2. It is largely for this reason, I believe, that in addition to whatever problems there are about the notion of identity in general there has always been felt to be a special problem about personal identity. It is, for example, the way in which one knows one's own past that has led some philosophers to hold that personal identity is the only real identity that we have any knowledge of, the identity we ascribe to ships and stones being only, as Thomas Reid expressed it, "something which, for convenience of speech, we call identity."
  3. What I wish to do in this paper is to consider how the concept of memory and the concept of personal identity are related. In particular, I want to consider the view that memory provides a criterion of personal identity, or, as H. P. Grice expressed it some years ago, that "the self is a logical construction and is to be defined in terms of memory."


"Shoemaker (Sydney) - Persons and Their Pasts"

Source: Shoemaker - Identity, Cause and Mind

Author’s Introduction
  1. Persons have, in memory, a special access to facts about their own past histories and their own identities, a kind of access they do not have to the histories and identities of other persons and other things. John Locke thought this special access important enough to warrant a special mention in his definition of "person," viz.,
      "a thinking, intelligent being, that has reason and reflection, and can consider itself as itself, the same thinking thing, in different times and places. . . ."
  2. In this paper I shall attempt to explain the nature and status of this special access and to defend Locke's view of its conceptual importance. I shall also attempt to correct what now seem to me to be errors and oversights in my own previous writings on this topic.


"Williams (Bernard) - The Self and the Future"

Source: Williams - Problems of the Self
Write-up Note1 (Full Text reproduced below).
  • For a précis and discussion, click File Note (PDF), now replaced by this Note2.
  • This text appeared in Commensal (Mensa) and in Aitia (Birkbeck).

  1. Also published in:-
  2. Printout filed in "Various - Papers on Identity Boxes: Vol 19 (W)",
  3. See "Funkhouser (Eric) - Notes on Williams, 'The Self and the Future'" for Notes,
  4. Originally in The Philosophical Review, Vol. 79, Issue 2 (Apr., 1970), 161-180).

Write-up3 (as at 21/04/2018 20:05:17): Williams - The Self and the Future

"Williams (Bernard) - The Self and the Future" – An Analysis and Critique4

Introduction: An initial Question
    Is it possible that you could exchange bodies with someone? You are to understand 'possible' not as 'practical' or as 'possible', but only as something that is coherent or possible in thought. If you think it is possible, describe the circumstances that would have led for this to happen. And if you think it impossible, say why.
  1. This question is raised preparatory to discussing a thought experiment described in Williams' paper. A similar idea, to which Williams is reacting, occurred in the late seventeenth century in Chapter 27 of John Locke's Essay Concerning Human Understanding, in which Locke imagines a Prince's consciousness inhabiting the body of a cobbler.
  2. Technicalities aside (a wiring problem) there seems nothing conceptually incoherent about having one's own brain transplanted into another's body. The alternative is the "dump and restore" technique - where the contents of one's brain (one's memories and presumably one's capabilities) are copied onto a storage device and then further copied onto the physical brain of another, overwriting or erasing whatever was there beforehand.
  3. There seems nothing utterly inconceivable about either of these techniques, but they seem to be conceptually different. Williams recognises that describing such thought experiments as "changing bodies" begs the question of what constitutes the substrate of consciousness and what makes up an individual person.
  4. The "brain transplant" approach has the benefit of some physical continuity, as the brain is a physical thing, and we are reasonably confident that the transplanted brain would be capable of retaining its information processing capacities. It would have a new body to get used to, but we would expect the mental abilities and memories of the transplantee to be as they were beforehand, though the physical abilities would be much changed and mental functioning would be affected by a different hormonal and respiratory environment and by a different sensory apparatus. Whether the hybrid felt himself to be the same person after this procedure would depend on that person's self-image and capabilities. A man whose abilities and aspirations were predominately physical (such as a boxer or footballer or even a musician or painter) would presumably not feel himself the same person after the operation, because it is not likely that these capabilities would cross over successfully, though a philosopher might not consider himself so badly off. Saying you have "exchanged bodies" while retaining your personhood would imply that your body was not of much significance to you as a person other than a rather passive vehicle for your mind. Not many people can say this.
  5. The "dump and restore" approach leaves the added complication of possibly cloning the original person (or at least their consciousness) - the original "me" can be left there undisturbed, after the contents of my brain have been copied, to awake as before. There is no necessity to copy the other person's brain-contents into my brain. I don't feel fully confident that the "restored" me would actually wake up - maybe it would be a zombie - though presumably a non-vitalist should have the courage of his convictions. Life would presumably be even harder for the new me in this "asymmetrical copy" case than in the "brain transplant" situation, as I would not only have the rest of the world confusing me with the previous owner of the body I then occupy, but I would have to contend with someone with a prior claim to being me - though as he is in on the act, this might be more of a help than a hindrance. It is this asymmetrical situation, which Williams turns to right at the end of his essay, that raises the most interesting questions.
  6. Enough of this pre-amble … we'll see how these initial prejudices (admittedly already influenced by Williams) change after some serious consideration of Williams' thought experiment. We now analyse in some detail what Williams has to say in his essay.

Analysis of Williams' Paper
  1. Williams asks us to consider his (tendentiously-entitled) "exchanging bodies" experiment. We have before us two persons, A and B, each with their own memories and characters and distinctive physical mannerisms for displaying them. After the exchange, however achieved, body A displays the memories and character of person B by physical manifestations appropriate to person B, and vice versa.
  2. Williams adopts a simplifying assumption to make the experiment more likely to be understood as that of "exchanging bodies" - he assumes some similarity between A and B so that there is a good chance of B's mannerisms in A's body not being made unrecognisable by gross physical or psychological differences between A and B.
  3. For us seriously to be convinced by the B-ishness of A-body's post experimental character, another condition must obtain according to Williams. B's memories must be reflected by A's body in such a way as it seems true that there is a causal chain between B's experiences and A-body's demonstration of apparent first-hand experience of them (presumably to guard against the supposition that A had simply studied B's background and the "memories" are learned rather than records of first-hand experience). Williams insists that the causal chain should not run outside of A's body, and therefore the simplest way to ensure this is by transplanting B's brain into A's body. However, Williams thinks a less radical version of copying B's memories and then restoring them to A's brain will suffice, for the reason that of the three grounds for knowing about one's own past - remembering, being reminded and learning again - there is no sufficient reason for describing the restored memories of B in A as "learned again". It is an interesting question whether this will do, because for A-body to be B, he needs not only B's memories, but B's information processing abilities. It is an open question whether the contents of B's brain can be copied onto different hardware (or in this case "wetware") while retaining the B-ishness of B. The restore mechanism would need to reconstruct the entire structure of A's brain to be as B's (which it might have to do in order to accomplish memory transfer, as memories are (most likely) physically encoded as connections between neurons). However, the firing rates of these neurons would presumably remain A's. Hence, I prefer the brain-exchange as the most likely method of "exchanging bodies". This form of the experiment is not, however, as interesting.
  4. After this exchange, we have the A-body-person and the B-body-person (where the A-body-person is the person occupying the body that was A's prior to the experiment). Those unaware of the experiment will initially presume the A-body-person is A, while the description of the process as "exchanging bodies" presumes that the A-body-person is B. A non-question-begging approach leaves it open as to whether either the A- or B-body-person is A.
  5. Williams now tries to determine which person is which using a thought experiment from the third-person perspective. A & B are informed before the procedure that post-operatively one of A- and B-body-persons will be tortured and the other given $100,000. They are asked what, on selfish grounds, they would prefer to happen to which. Williams notes that, depending on the choices of the victims, the experimenter may or may not be able to satisfy both of them, but that their choices and reactions to being told prospectively what is going to happen will reveal how they understand the procedure to work in accord with personhood. As Williams notes, while if the post-operative state is announced beforehand it makes sense to say prospectively that A or B got what he wanted, it is an open question whether retrospectively either of them can be said to have got what he wanted, as this begs the question that either of the A- or B-body-persons is A or B, or whether, for instance, they have been hybridised.
  6. Williams suggests that there are good grounds for presuming that we could say retrospectively that either A or B got what he wanted. He takes the case where A and B presume this to be an "exchanging bodies" experiment, so that A chooses that the B-body-person receives the good treatment and B the A-body-person. He then further supposes that the experimenter in fact awards the good treatment to A and the bad to B, though he doesn't tell them beforehand. After the experiment, the A-body-person, with B's memories, remembers that he chose the good outcome and is doubly satisfied on the grounds both that he got what he wanted and that what he got was good. The B-body-person, with A's memories, is similarly doubly dissatisfied. At face value, this seems to imply that B chose wisely, got what he wanted, and that the A-body-person really is B, whereas A also chose wisely, but was unlucky, and that the B-body-person really is A - and that "exchanging bodies" is a correct way of describing the experiment.
  7. That the A-body-person really is B and that the B-body-person really is A can be made to seem probable by variations on the experiment - eg. with the same experimental outcome as before, A chooses that the A-body-person receives the good treatment and that consequently the B-body-person is unhappy with the outcome, but acknowledges that this is what he chose and that he chose unwisely (and similarly, mutatis mutandis, for the B-body-person). Finally, Williams considers the hybrid case where A chooses unwisely and B wisely, with the experimenter acting as before. Both get what they chose, but B-body-person is happy, A-body-person unhappy with the outcome. All three cases seem to support the "exchanging bodies" hypothesis.
  8. Williams now starts to expand the perspective of the experiment by considering the post-operative responses of A- and B-body-persons to their bodies (he is careful not to describe them as B & A respectively, though notes that their responses would be consistent with this assumption - he also notes that if they had viewed the experiment as changing bodies, they would have had to be reasonably satisfied with these bodies before agreeing to take part in the experiment at all). He tries to tease apart the consequences of the supposed body-swap by asking questions such as, if the B-body had a wooden leg that B had become habituated to, would the post-operative B-body-person also be habituated to it; ie. is the habituation a mental or a physical thing?
  9. Williams now proceeds to consider the matter laterally by thinking in detail about A & B's psychological expectations, concerns and responses. In particular, he stops begging the question by presuming that the experiment results in A and B exchanging bodies. It thus at least makes sense for A and B to ask whether, post operatively, they may be able to escape some of the mental hang-ups they currently have. So, he imagines A with bad anxiety and B with fearful memories, but concludes that the post-operative B-body-person would possess this proneness to anxiety while the A-body-person would have the bad memories. This is still consistent with the "exchanging bodies" hypothesis, and so far the argument leads us to conclude that the requirement for bodily continuity as a necessary condition for personal identity is mistaken and that, as Locke thought, we should identify ourselves with our memories rather than our bodies.
  10. Williams now considers what appears to be a different thought experiment, but which is really the previous experiment this time viewed from a first-person perspective. I am told that tomorrow I am to be tortured, but with allegedly increasingly ameliorating circumstances, as below:-
    • Shortly before the torture I will forget that I have been forewarned
    • I will lose all my former memories
    • I will be given a new set of memories, ie. a new past
    • That my then memories will correspond to those of another person now living
  11. The point is that, at no point in this Sorites-type5 argument will I feel any comfort; rather, I will feel even more disquieted - for (despite being told how this is to be brought about) not only would I still have the prospect of torture to endure, but would have mental derangements equivalent to total amnesia and madness imposed on me as well.
  12. As this is just another view of the first experiment, can we confidently say this view, rather than the first, in which I would be happily escaping from the soon-to-be tortured body, is wrong. Williams thinks not. The experimenter may simply be intimidating me by persistently using the term "you" to me - thereby begging the question in the opposite direction to the "exchanging bodies" perspective - but it seems clear that, at the moment of torture, whatever impressions I have of the past will not influence my then present pain, and in reviewing the process there seems to be no point at which I've been "beamed up" into another, happier body.
  13. Williams now briefly explains why he's chosen the example of torture as a future dread event, rather than some other thing one might fear. This is because many of our fears are character- or memory-based, which, in this experiment, are likely or known to be about to change. However, aversion to physical pain is minimally character- or belief-dependent. Having started on this aside, Williams also points out that it may still be valid to fear a psychological disturbance in which our then selves would be perfectly happy - as in our being turned into contented vegetables - and the reason we would fear such a turn of events would be selfish rather than the altruistic acknowledgement that we'd be unable to fulfil our obligations. Personally, I do not view this as a paradox of hedonistic utilitarianism (nor, I suspect, does Williams). What makes our pleasures so exquisite is that we have chosen to have them, maybe struggled for them, and so the utility of a life of our own, with all its vicissitudes, exceeds that of one in the orgasmatron6.
  14. Returning to the chase, Williams now points out the second difference between this first-person report of the events and the "exchanging bodies" one - there is no mention of the second person, other than as the source of my new memories. From this first-person perspective, this second person is irrelevant except as an object of our envy, but in the third person account this is the new me, the one on whose account I ought to be afraid, if at all. One who subscribes to the "exchanging bodies" interpretation of events will count this as a fatal objection to the first-person account. However, Williams doubts this is so.
  15. To demonstrate why not, Williams rehearses the first-person account again, imagining the torture occurring at the end of each of the six steps in the process (starting with me suffering total amnesia, and ending with the other person undergoing the analogous character-change to that which I undergo). Since these steps are important for subsequent discussion, and already succinctly summarised by Williams, I have filched them verbatim from Williams' paper:-
    1. A is subjected to an operation which produces total amnesia;
    2. amnesia is produced in A, and other interference leads to certain changes in his character;
    3. changes in his character are produced, and at the same time certain illusory 'memory' beliefs are induced in him: these are of a quite fictitious kind and do not fit the life of any actual person;
    4. the same as (iii), except that both the character traits and the 'memory' impressions are designed to be appropriate to another actual person, B;
    5. the same as (iv), except that the result is produced by putting the information into A from the brain of B, by a method which leaves B the same as he was before;
    6. the same happens to A as in (v), but B is not left the same, since a similar operation is conducted in the reverse direction.
  16. At the prospect of none of these six cumulative experiments do I feel anything other than disquiet. This is because from this perspective at no stage do "I" (A) escape into the other person's (B) body.
  17. Viewing everything up to the fifth step (copying B's dispositions & memories into A's brain while leaving B otherwise alone), Williams thinks we have two answers to the "exchanging bodies" objector. Firstly, there is no reason (given the primal pain aversion common to us all) why I should not be just as afraid of torture, even with B's dispositions, as normal. Secondly, because B still exists undisturbed, A-body-person (me) cannot be (numerically) the same person as B as there are two persons with a claim to B-ness. Locke would say there are two men but only one person. I would agree with this, but only for an instant - the two men diverge into two persons as soon as either has an experience (I wanted to say "has an experience not shared by the other" but feel that even if their experiences were miraculously kept synchronised they would still be two persons because they are two consciousnesses). From the "exchanging bodies" perspective, if we stop after step five, A has died (or is at least in suspended animation) and B has been partially cloned. This situation is critical. B's consciousness cannot have "hopped" to body-A as it must still be in Body-B at this stage. So, what consciousness is in Body-A? It is tempting to think of this consciousness as a scrambled version of A's, but we "exchanging bodies" types7 should maybe stick to our guns and assert that the consciousness in Body-A is also B's; for the consciousness in Body-A it will feel like B having swapped bodies, and having temporarily a mental twin in Body-B, though because of its necessarily different environment it will rapidly diverge from Body-B's. Williams’s assertion that at the end of step five A-Body-person and B-Body-person are certainly not the same person is too strong (though, as I noted, they soon would be).
  18. Williams now tries to find out whether we can make out that the transition from (v) to (vi) is important for A, and does not simply refer to something happening to someone else (B). The point is that, at the end of (v), B-Body-person is very definitely B, so if A-Body-person is not A, then no-one is. This seems fair enough (as I've alluded to above), but if A doesn't exist at (v), when in the process does he disappear? Williams argues that A still existed after (i) and (ii), that is, after the total amnesia and personality change, so maybe we should draw the line after (iii) or (iv), memory exchange with a fictitious person or, in (iv) B. Williams question is rhetorical, presuming a "no" answer. I think, though, that he gives insufficient weight to the catastrophic nature of the changes affecting A-body-person. His analogy is with the normal amnesia, personality disorders or delusory memories that might afflict someone going out of his mind. Well, if someone had been afflicted to the total degree suggested in the thought experiment, we would forensically count them as having become a new person, and treat the original person at least as being in abeyance. The question is, when would A suddenly suffer a dislocation of consciousness, so that a new person with no historic conscious continuity with A pop up in A's body. Personally, I think this would be after step (i), the total amnesia, though possibly after (ii), the total personality change. We could apply more granular Sorites-type8 arguments against this (memory draining away bit by bit, personality changing gradually) and ask just when does A cease to exist? This is not the same situation, however - A would be adjusting to this unfortunate state of affairs and would evolve into A*. We wouldn't be troubled by such thoughts in the "brain transplant" version of the experiment. If A's brain was taken out of A's body, there would be no chance of A's consciousness remaining there, not even in his little finger9!
  19. Williams now repels a rather silly proposal, along the lines that we can't decide whether or at what point A-body-person ceases to be A, so why worry about it; some things are just like that. Well, Williams adopts the first person perspective of A, and points out that, while this situation might be acceptable for a third party, it is of vital interest to A, who is either going to be tortured or not depending on the outcome. I have to say I can almost feel Williams being argued into accepting Pascal's wager (after all, what is worse than being tortured for ever!), so there must be something dodgy going on here. Williams labours the rather obvious point that I will retain fear at the prospect unless I am sure that I won't be involved in the unpleasant things yet to happen to A-body-person, and will be fearful in proportion to the probabilities involved. Williams seems to be suggesting that in this case, the situation must resolve itself one way or another - the coin has to be heads or tails - A-body-person will either be me or not, but until I know which, I have good reason to be in trepidation.
  20. Williams thinks that this situation of undecidablity is unthinkable from a first person perspective in that if I lose my fear on account of the undecidablity, I have effectively decided that it will not be me who will be tortured, while if I continue to worry about it, it is because I think it will be me. Williams tries to envisage whether I might adopt ambivalent concern towards the event, as I might towards something to which I was sentimentally attached that underwent some puzzling confusion of identity. Williams, of course, thinks this won't do, for as soon as I adopt this ambivalent stance towards A-body-person, while I may be hazy about who he is, I've already concluded that he's not me. If I still thought he might be me, I wouldn't be so detached. I think that Williams is getting into a muddle here, and mutiplying zero by infinity and getting any number he likes (as in Pascal's wager). If the prospect was a remote chance of a slapped wrist rather than unbearable torture one would easily become dispassionately involved.
  21. Williams states that "there seems to be an obstinate bafflement to mirroring in my expectations a situation in which it is conceptually undecidable whether I occur". Isn't this parallel to any future contingency? What's the difference between this and being worried on being told that all first-year BA students who fail their exams will be mercilessly tortured. While I might concur that this sentence, though just, is unlikely to befall me - I would do well to fear it because, confident though I may be, there is no way of knowing that I will pass.
  22. Later, Williams considers, returning to the six-stage experiment, whether we might not choose to identify A with A-body-person after stage (v) because there is no better candidate, but not after (vi) because B-body-person will then do much better. Williams thinks this is like disposing of the effects of some intestate relative - we just have to decide as best we can within the confines of the law. Williams rightly doesn't think this will help A at all, for if he's still frightened at the prospect of (v), the thought that there would be a better candidate for A-ness after (vi) will not console him.
  23. When Williams starts to sum up, he thinks the opposite conclusions reached by the third and first person perspectives of A's fate are conceptually undecidable, and that he's not sure which choice he'd make were he to have the bad luck to be A. Not surprisingly, he's disturbed by this (he's taking his thought experiment rather too seriously, one might think). Williams brings up the dichotomies between, respectively, first and third person perspectives and "mentalistic" and "bodily continuity" considerations involved in questions of personal identity. Williams points out that his thought-experiments have revealed a reverse parallelism to that usually considered for these two pairs of concepts - the third person perspective is here associated with "mentalistic" considerations while adopting a first person perspective led us to support bodily continuity. Williams considers this inversion of some enigmatic significance.
  24. Finally, Williams considers whether the presentation of the third-person perspective in its neat symmetrical form unfairly induced us to consider it as "exchanging bodies". This is a very important point, and in my view more space should have been devoted to it at the expense of the angst-ridden ramblings that occupy most of the latter half of the paper. Clearly, according to the rules of the experiment, we could have generated any number of A's and B's in any number of brains / bodies. This is in sharp contrast to the more invasive, but allegedly equivalent, "brain swap" alternative experiment. This leads me to feel there is a little bit of slight of hand in Williams' introduction of his non-invasive equivalent, which is not equivalent in the least - though depending on what Williams is seeking to demonstrate, this lack of equivalence may not matter. The possibility of "me" being "restored" into the brains of numerous bodies (while being left alone in my own body - let the reader please forgive the tendentious language here!) makes it unlikely that my consciousness would flip over into B-body-person at any stage in the experiment - otherwise, in variants of the experiment, I could be saddled with an open-ended number of (presumably incommunicable) selves to cope with. We would have to suppose that these new consciousnesses, for all their similarities to me, are not me, and that in the experiment both A and B die, with two new consciousness emerging in their places.
  25. So, Williams comes down to the decision that if he were told that he (as the A-body person) could choose who would have the post-operative torture, he would choose B, being convinced by his psychological angst arguments. My view is that, in Williams' "dump and restore" variant of the experiment, I would opt out because both A and B are dead, but in the "brain transplant" version, assuming I'm confident of surgical success, I'd choose the easy life for the body with my brain in it any day.

Further Questions

At Birkbeck, we are supplied with a Commentary that expatiates on aspects of the passage under discussion and asks (and sometimes sketches answers to) various questions. Because answering questions not surprisingly tests comprehension, I'll seek to answer some of the questions and you must let me know whether you agree with the answers:-
  1. Say which of the following seems the best account of what will have happened in the initial "third person" account of Williams' thought experiment:
    1. A turns into B, and B turns into A.
    2. A comes to inhabit B's body, and B comes to inhabit A's body.
    3. A and B will both die and two other people emerge, say A+ and B+.
    Can you think of any other descriptions that fit what happens more closely?
    • The fourth description (d) sought by the question would be that all sorts of horrid mental events happen to A and B, including total amnesia, character change and implantation of someone else's memories, but that A-body-person remains A and B-body- person remains B.
    • Description (a) is inadequate because what makes A or B a person includes both somatic and mental attributes, and the post-operative individuals are hybrids of A and B; the function "turns into" loses this sense of what's happened.
    • As discussed above, in the case of the "brain transplant", I would favour (b) as the best description, while for "brain copying" I would favour (c).
    • In case of brain transplantation it is not possible for any of A's conscious experience to remain behind in A's body, which rules out (d). The effect on A of finding himself in B's body, with different somatic, sensory and hormonal structures to get used to, would be exceedingly traumatic, but, though A would necessarily lose consciousness while the operation was performed, we (or at least I) can just about imagine him waking up feeling highly disorientated, but still feeling, as in (b) that he was A and not, as in (c), A+.
    • One reason I'm reluctant to support (b) in the "brain copying" example is the (science-fiction-) fact that multiple copies can be made of A's mental structures and parked in as many Xi-body-persons as we wish, and can they all be A? However, and I believe this to be a very important point, while we're making use of the technology, we could go further and use our matter-copier to clone A's physical brain multiple times and wire him up in the Xi-body-persons, or go the whole hog and clone the whole of A producing the set {A*i}. Would all these A*i's feel themselves to be A? I think it's clear that, subject to the caveat in the next paragraph, they would, though, like twins, they would instantaneously diverge into separate persons as they developed further.
    • One caution - given how little consciousness as a phenomenon presumably derived from physical processes is understood - we should not get carried away by our thought experiments; for all we know we may be suggesting techniques that are not just impractical but impossible (as, for instance, would be the case if there was some immaterial soul that animates a person and that couldn't be cloned or copied by our ingenious devices). The metaphysical assumptions as to what makes up a human being are not made explicit in Williams' paper. It does seem, though, that the first-person perspective tacitly assumes that there's something more to "me" than the contents of my brain and that it's this "me" that continues in my original body as the (highly disturbed and utterly disorientated) person with a new mind. The first person perspective might almost be described as "exchanging minds", which is an even more difficult concept to get our heads round that "exchanging bodies".
  2. Williams considers different things that A and B might say if they were asked to choose the fate of the A- and B-body-persons, and also what they would say about their willingness to undergo the experimental operation. Summarize these various options in your own words.
    • Williams considers various responses (which I detailed above) all based on the "exchanging bodies" paradigm that A's consciousness ends up in B-body-person and vice-versa. From this third-person perspective, A chooses wisely if he chooses pleasant things to happen to B-body-person. Whether A would like to play this game would depend on what he thought of B's body and whether he found the prospect of occupying it appealing.
  3. If, when you answered the earlier exercise, you thought that this (ie. A and B changing bodies) was not the best description of the case, has the series of choices and estimates of outcome changed your mind? If not, what do you think might be wrong with the way these choices are described?
    • As Williams later points out at the end of his essay, the "exchanging bodies" paradigm is made more plausible by the perfect symmetry of the operation, whereas we might stop the procedure after we've copied B into A but before we've copied A into B. Also, though we've followed A & B's prudential thought-processes, we've not put ourselves firmly enough in their shoes to experience the angst they would feel at the possible results of the experiment for them, and hence may have missed out on the possible continuing A-ness of A-body-person.
  4. Williams considers ways in which one might resist this conclusion about the second of the perspectives on the example (ie. considered from the first-person perspective, at no stage does it seem as if you and the other change places). The arguments here are careful and sometimes dense, but you should read them over several times, and try to summarize them in your own words.
    • Williams doesn't seem very convinced that the first-person conclusion can be resisted, because, firstly, as A views the prospect before him, as summarised in Williams' (i) to (vi), at no stage does his fear abate, and in particular not at step (vi) which from this perspective appears to be something happening to someone else. The key point is after (v) when B is very much alive and kicking, but A has not been reconstituted. Where is A, and who is A-body-person if B is still B? How do we resist the conclusion that A-body-person is still A? Williams doesn't hold out much hope for doing so, but recognises that someone committed to the exchanging bodies view will take it that step (vi) involves the re-introduction of A, who had at sometime prior thereto dropped out of the plot. Williams' problem is just when this might have been - he thinks it unlikely after (i) - amnesia - or (ii) - character change - and thinks it would have to be after (iii) - fictitious memory introduction - or (iv) introduction of memories modelled on B's. I've argued above that Williams underplays the catastrophic nature of these changes and that he ought to be more sympathetic to A dropping out of the picture after (i).
  5. Williams presents several arguments against the strategy based on thinking of our concept of a person as sometimes undecidable. Summarize his points in your own words.
    • This strikes me as the most difficult part of the essay. Williams rejects the idea that abandoning hope of clarity on the grounds of formal undecidability may provide some comfort. While it may supply some to third party observers of A's situation, it will supply none at all to A who is, potentially at least, intimately and disastrously involved. To clarify the situation, Williams asks us to consider a future situation S at which we (in fact, I) may or may not be involved. I will only feel fear at the prospect of S if I expect to be involved (and, of course, if I believe there is something in S for me to fear). If some dread event is going to befall one of a company of people, of whom I am one, my apprehension will rise to fear in proportion to my imagining that the one will be me. Moreover, I know that this situation will resolve itself and that it will either involve me or not. Williams also says that I may be neurotically apprehensive of some indeterminate ill from some range of possibilities, or even of some nameless horror, but the common factor for me to display fear at the prospect of one of these things happening is that they should happen to me. When I think that S may involve me, I am able to imaginatively project myself forward to my involvement in the event.
    • Williams now returns to our experiment, and finds A's predicament to differ from the indeterminacy in the examples just cited. It is not like the nameless horror, since that, whatever it was, was definitely going to befall me, nor is it like the probability case, where it would either involve me or not, depending on how the situation worked out. A's (my) fear of torture in the experiment seems neither appropriate (as it would be if I knew myself to be A-body-person) nor inappropriate (if I knew myself not to end up as the A-body-person), nor is it appropriate for me to be dispassionately equivocal, since the stakes are too high.
    • Williams seems to argue that if I try to imagine myself present at some situation S at which it is formally undecidable whether I will be there or not, then if my effort of what he calls projective imagination is successful, then I have effectively decided the situation in the affirmative, while if I am unsuccessful I've decided it negatively. Personally, I cannot see what is demonstrated by one's ability, or lack thereof, to work oneself up into a lather of apprehension. I find a later argument even more confusing. Williams states that "material objects do occasionally undergo puzzling transformations which leave a conceptual shadow over their identity". An example of what this is supposed to mean would have helped. Whatever this is supposed to mean, we are to imagine that we are sentimentally attached to some object which undergoes this strange transformation, so that afterwards we are supposed now to feel ambivalent concern for it - neither as we did before, yet not totally disinterested. Not surprisingly, Williams does not think this a fair model of the situation envisaged when I'm not sure whether or not I'll be present at situation S, but that if I am something nasty is going to happen to me. I will not feel ambivalent concern for the person involved - I will feel terror on account of it possibly being me!
  6. Williams dismisses this second, conventionalist, way of evading the problem (of being precise in our definition of a person). What is his reason for dismissing it?
    • Williams' view is that whatever forensic decision is given by third parties on this subject, this is of no use to me who is vitally involved. If the conventionalists have decided that the best candidate for being A after (v) is A-body-person, to whom nothing further happens (apart from being tortured, of course !), the fact that there is a much better candidate after (vi), namely B-body-person, will be no consolation, as we had no necessity to proceed with step (vi) at all, so, from a forensic perspective, he might have been left as the unfortunate A-body-person.
  7. In the final paragraph of his essay, Williams tentatively suggests a resolution to the conflict between the two cases. Say what his conclusion is, and what argument he uses to reach it. Finally, give some reasons for either agreeing or disagreeing with him.
    • Williams' comes down tentatively on the side of the first-person perspective, and says that if he were A, he would choose for the torturing to happen to B-body-person. His reasons are that we were deceived by the symmetry of the third-person perspective experiment into considering it as an exchange of bodies, whereas if the experiment had been conducted asymmetrically (eg. only as far as the equivalent of (v)), we would not have been so convinced that this was the correct description of the procedure. As I have previously stated, I think Williams gives insufficient weight to the drastic changes that come over A- and B-body-persons, and that if the focus was on brain-transplantation, which is allegedly parallel to the experiment being performed, he would be on the side of the body-exchangers.

In-Page Footnotes ("Williams (Bernard) - The Self and the Future")

Footnote 3:
  • This is the write-up as it was when this Abstract was last output, with text as at the timestamp indicated (21/04/2018 20:05:17).
  • Link to Latest Write-Up Note.
Footnote 4:
  • This essay is based on one of my first Supervision papers in my first year at Birkbeck, and appeared as here in February 2001 in Mensa’s Commensal when I edited it.
  • A version appeared in Aitia the Birkbeck Student Philosophy magazine, in the Summer 2002 (Volume 2) edition. From a quick check, the text seems unchanged.
  • I’ve not changed the text – see later versions (if any) for my current understanding.
Footnote 6: This allusion to Woody Allen's Sleeper was made before the recent announcement of the invention of such a device, honest!

Footnote 7:
  • January 2016: did I ever really believe this?
  • I’d thought I’d always agreed with Williams that exchanging bodies – other than by a brain transplant – was impossible.
Footnote 9: An allusion to another thought experiment by Locke.

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