Handout 14 Locke on Personal Identity 1. Three Uses of Terms Like ‘Identity’ 1. To refer to a self-conception. E.g: ‘My fascination with philosophy threatens my identity as an experimental scientist’. 2. To refer to the relation that holds between things that share many intrinsic properties. E.g: “These two paper clips are identical.” We may call this qualitative identity. 3. To refer to the relation that holds between each thing and itself, and nothing else. We may call this strict identity. Questions about strict identity typically come up when you know that there is one thing with features F, and that there is one thing with features F*, and you ask: “Is the thing with features F the thing with features F*?” Examples: Is the youngest person in this room the tallest person in this room? Is the third perfect number the 28? 2. Strict Identity Over Time We’re going to be interested in strict identity but across time. Questions about strict identity across time come up when you know that there is one thing with features F at time t1, and that there is one thing with features F* at a later time t2, and you ask: “Is the thing with features F at t1 the thing with features F* at t2?” Examples: Is the shirt you’re wearing the one I gave you for your birthday? Is the person I saw at the coffee shop this morning the same as the person I sat next to on the airplane yesterday? We care a great deal about questions of the identity of persons over time: Is the person I am pointing at now a person who will be given a million dollars tomorrow? Is the person I am pointing at now going to be suffering from a horrible illness next year? Is the person I am pointing at now one of the people who will be alive tomorrow? Is the person on trial today the person who committed the murder three months ago? 3. Locke’s Criterion of Persistence Over Time For Masses Whenever A is mass that exists at one time, t1, and B is a mass that exists at a later time, t2 A is B iff every part of A at t1 is a part of B at t2, and vice-versa 1 Locke’s Criterion of Persistence Over Time for Organisms (‘Vegetables’, ‘Animals’, ‘Man’) Whenever A is an organism that exists at one time, t1, and B is an organism that exists at a later time, t2 A is B iff A and B ‘partake in the same life, though that life be communicated to new particles of matter vitally united to the living [organism]’ In other words: there is a kind of organizational continuity that exists between an organism at different times which is what makes it a single organism. (Compare: a club, 24.00) Locke’s Criterion of Persistence Over Time for People Whenever A is person who exists at one time, t1, and B is a person who exists at a later time, t2 A is B iff at t2, B remembers A’s actions and experiences at t1. (Note: in what follows theories of personal identity over time will assume that A is a person who exists at t1 and B is a thing that exists at a later time, t2). 4. Objections to Locke from Reid and some Modifications Objection 1: He ‘Mistakes Testimony for the thing Testified’ According to Locke, my remembering doing something makes it the case that I did it. But isn’t that objectionably circular? Isn’t it part of the concept of remembering that I only remember the things I did? Modification to Avoid Reid’s First Objection Say that I quasi-remember doing something when I am in a mental state that is intrinsically just like the one I would be in if I remembered doing it. A is B iff at t2, B quasi-remembers A’s actions and experiences at t1. Objection 2: Locke is Saying that Strict Identity is Intransitive Say that a relation is transitive when, for all things x,y,z, if x bears the relation to y, and y bears the relation to z, then x bears the relation to z. Strict identity is a transitive relation. But, when lives are long and memory is short (e.g. the boy, young officer, general), remembering is intransitive. The general remembers being the young officer, the young officer remembers being the boy, but the general does not remember being the boy. So Locke cannot be giving a criterion of strict identity. Modification to Avoid Reid’s Second Objection Say that A’s mental state at t1 is memory connected to B’s mental state at t2 iff at t2, B quasiremembers being A at t1 Say that A at t is memory continuous with B at t’ (the ancestral of the forward memory connected relation) iff either A at t is memory connected to B at t’, 2 or there is a chain of persons C1, C2, C3…Cn that exist at times t< t1…tn-1