Introductory summary by Ted Honderich of Derek Parfit’s Royal Institute of Philosophy Annual Lecture



            Derek Parfit, born of medical doctors teaching in missionary hospitals in China, was educated at Eton and in Oxford, where he studied modern history. After a year at Columbia and Harvard, where he turned to philosophy, he became a fellow of All Souls College in Oxford, and is now an Emeritus Fellow. He is also a regular visiting professor at Harvard, New York University, and Rutgers. To his commitment to philosophy he adds one to photography.


            If you saw somebody distinctive in the Broad in Oxford a year ago and somebody similar yesterday, what would make them the same person? What is the criterion of personal identity, of being a particular person? There once was the idea, and still is, that they would have to be one and the same self, subject, or maybe soul -- an internal and unphysical entity, one that has experience rather than somehow consists in it. There is also the second idea, argued for by Bernard Williams among others, that the two would have to be one body -- there would have to be physical continuity.


            There is the third idea whose origin is assigned to Locke in the 17th Century. It is that the person today is the person of a year ago if today's person remembers, as their own, actions that were performed by the person a year ago, and also the person today may be acting on an intention to visit Oxford formed by the person a year ago, and also have some identical beliefs and the like. In sum, there is psychological continuity. Parfit is best known for his formidable development, partly in terms of further ideas of uniqueness, cause, and brain, of what is called this Lockean idea. That was in his uniquely methodical and regulating book Reasons and Persons.


            To these three responses to the problem of personal identity has more recently been added what has been known as the idea of animalism, that two persons are the same person if they are the same animal or human animal -- if there is what is also called biological continuity. Parfit takes and speaks of this as the view that personal identity is a matter of same human being, and so in the title of his lecture denies that we as individual persons are individuated as human beings.


            It is his main concern in his lecture to refute this view but also, so to speak, to learn from it. Proceeding by imagined cases or thought experiments like those that have been the main content of the philosophy of personal identity, he first considers objections by animalists to the Lockean idea, and then considers problems for animalism or biological continuity and also for the Lockean view and how the views do or do not solve them.


            Partly prompted by animalism, he moves thereafter to the Embodied Part View of personal identity and then on to the principal contention  of the lecture, that the truth about personal identity is the Embodied Person View. It is mainly a development of his original Lockeanism -- a development to the effect that each person is an embodied conscious, thinking, and controlling part of a body, animal or organism. It is no more a physicalism about personal identity than he originally had in mind. As remarked elsewhere, he continues to find physicalism implausible but rejects Cartesian dualism, and has not thought about the mind-body problem, regarding it as too difficult.


            What follows in the lecture is consideration of objections to the Embodied Part and the Embodied Persons View, much of this consideration by way of the proposition that the pronouns 'I' and 'you' are in a way ambiguous. Finally the possibility is considered of whether the lecturer has undermined his own original case by his development of it. He also considers a strengthening of what was an upshot of his original view -- that personal identity cannot be what matters, or anyway what matters as much to us as before we come to understand it rightly.


            All of the lecture is a typically indefatigable train of argument. It is a sequence of particular proofs, or particular propositions akin to proofs, that add up to something  about as approximate to proof of a whole theory as the unique difficulty of philosophy allows. It is a lecture like others in this volume that are more in need of encouragement in advance for readers than summary. It is also a lecture ending in generosity to animalist opponents, including Paul Snowdon, Eric Olson and others.


            Inclined as I myself am to a developed kind of Lockean and indeed Parfitian view of personal identity, I ask but one question. In philosophy and elsewhere, there is endless concern with subjectivity in connection with consciousness. Is it the same fact as personal identity conceived in a way like the one defended in the lecture?