Kaiserman: The Personite Problem Are persons ‘worms’ (aggregates of stages) or stages? An objection to the worm theory Worms or Stages? worm stages Assuming 4-dimensionalism, there is a further question: are ordinary objects, including people, 4-d ‘worms’ that have instantaneous stages as their temporal parts or are they themselves instantaneous stages? The Stage Language Jones Jones • On the stage theory individuals are just stages. • Names are systematically ambiguous (like indexicals) and refer to different things at different times—in this case, to different person stages After Fission Smith-Jones is in Chula Vista, Brown-Jones is in Florence The Stage Language Smith-Jones Brown-Jones Jones • Future tense statements about a person really say that the stage which he is, is Rrelated to another stage that is whatever. • [Before fission] Jones will be in Chula Vista after fission because the pre-fission stage ‘Jones’ picks out is R-related to a post-fission stage in Chula Vista Three Accounts of Personal Fisson The Branch Language The Lifetime Language The Stage Language Branches, Lifetimes, or Stages? • All three accounts assume (or are compatible with) a four-dimensionalist ontology but chop it up differently, i.e. have different accounts of what persons and other ordinary objects are, and all are bad in their own way. • Ordinary objects are lifetimes (Perry): cannot count timelessly at all. • Ordinary objects are instantaneous stages (Sider): gets synchronic counting right counting by identity, but in diachronic counting, for ordinary as well as fission cases there are infinitely many objects (though we can avoid talking about them) and no answer to how many people all along is fission cases. • Ordinary objects are branches (Lewis): ’Cohabitation’ in fission cases--two or (possibly many!) more then indistinguiable objects around before fission and The Personite Problem. In Support of the Stage Theory • Ontology is same as Worm Theory: difference just in semantics. - Names and other referring expressions designate instantaneous stages. - Persons are instantaneous stages but this isn’t to say they live and die moment by moment: they survive by being R-related to later stages. • The Worm-Theoretical Personite Problem: If persons are worms, they overlap innumerable ‘personites’, worm-segments that fall short of being maximal but have everything it takes to be persons other than maximality—and who, arguably, have interests and rights. Is it morally ok for me to sacrifice now to save for retirement when many shorter-lived personites won’t be around to cash in? Stage Theory & the Personite Problem Four-Dimensionalism and the Problem of Temporal People-Parts Contents Kaiserman defends four-dimensionalism against an argument by Mark Johnston which purports to show that it has unacceptable consequences, viz. commitment to the existence of personites. Personites are a problem for the Branch Theory but not for the Stage Theory! 1 Introduction: Worm Theory and Stage Theory 2 Preliminaries: Worlds, Times, and Persons 3 The Personite Problem 4 Objections and Replies A Problem for Four-Dimensionalists Mark Johnston has recently argued that four-dimensionalist theories of persistence have disastrous consequences for practical ethics. The problem, he argues, is that such theories are committed to the existence of personites, shorter-lived objects coincident with people; that personites have moral status on any plausible theory of how things acquire such status; and that this consequence is incompatible with even our most basic ethical and prudential assumptions. I will show that his argument only works on a perdurantist or wormtheoretic account of persistence, according to which people instantiate tensed properties in virtue of having temporal parts at past and future times, but fails on an exdurantist or stage-theoretic account of persistence. The Four-Dimensional World • Four-Dimensionalism is the view that every object has an instantaneous temporal part at every time at which it exists and comes in two flavors: the worm theory (‘purdurantism’) and the stage theory (‘exdurantism’) • Persons in the four-dimensional world: - Person-stage: an instantaneous temporal part of a person - The R-Relation: the relation that matters for personal persistence (‘personal identity through time’) • Worm Theory: persons are maximal R-interrelated aggregates of person-stages. • Stage Theory: persons are just person-stages. Persons’ Pasts and Futures • What was or will be true of me at a time, t, is grounded in what is true of my stage-at-t and states of affairs that obtain at other times. • According to the worm theory I have a past or future property at t in virtue of having an earlier or later temporal part that has that property - E.g. I will be in France in virtue of the fact that I have a future temporal part in France. • According to the stage theory I have a past or future property at t in virtue of the fact that I, a person-stage, am R-related, to an earlier or later person-stage that has that property. - E.g. I will be in France in virtue of being R-related to someone in the future who is in France. Personites • An object x is temporally continuous iff for all times t1 < t2, if x exists at both t1 and t2, then x also exists at all times t such that t1 < t < t2. • If x is a person, then y is a personite of x iff y is a temporally continuous nonmaximal R-interrelated fusion of two or more person-stages, each of which is Rrelated to every instantaneous temporal part of x. personite personite personite personite personite There are lots of personites! The Worm-Theoretical Person Puzzle Johnson: ‘[F]or each person there is an immense multitude of very person-like things…inhabiting parts of that person’s life…sums of continuous stages.’ ‘A personite is in all intrinsic mental and physical respects like its ”host” person over the period of existence of the personite.’ ‘What then could be the basis for granting the person moral status, but not the corresponding personite? What is so morally momentous about being maximal’? The Personite Problem Johnson argues that if there are personites they have moral status—and that’s bad. A Reductio Against Four-Dimensionalism • Reductio ad absurdem: A form of argument in which some statement is shown to be false because it has obviously false consequences. - For example, in proving theorems in math and logic by reductio we assume the opposite of the theorem to be proven and show that it implies a contradiction. To prove T, we assume NOT-T for reductio, show that it implies a contradiction and hence must be false—so that its opposite, T, must be true. • Johnson’s Reductio Argument Against Four-Dimensionalism (1) If Four-Dimensionalism is true then there are personites. (2) Personites have moral status, i.e. interests and rights that should be respected. (3) But it is obviously false that personites have moral status. (4) Therefore, Four-Dimensionalism is false. The Personite Argument So in support of the reductio, Johnson argues for its Premise 2: the claim that personites (if there are such) have moral status, as follows: (1) For all possible worlds w and possible objects x, if x is a person in w then x has moral status in w. (2) For all possible worlds w and v and possible objects x and y, if x in w is a duplicate of y in v, then x has moral status in w iff y has moral status in v. (3) For all personites x, there are a possible object y and possible world w such that y is a person in w and y in w is a duplicate of x in the actual world. (4) Therefore, all personites have moral status. Possible Worlds ways that things can be, could have been, or could come to be Possible Worlds World w z is a person, a maximal R-interrelated aggregate of person-stages, and so has moral status. World v y is a person, a maximal R-interrelated aggregate of person-stages, and so has moral status. Possible Worlds World w x is a personite and is an intrinsic duplicate of y. The only difference between x and y is extrinsic: x is ‘attached’ to later person-stages; y isn’t. World v y, an intrinsic duplicate of x, is a person, a maximal R-interrelated aggregate of personstages, and so has moral status. Possible Worlds World w Extrinsic differences, like being attached to later person-stages World v y is a person, a maximal aggregate of personstages, and so has moral status. Possible Worlds World w Extrinsic differences, like being attached to later person-stages don’t make a moral difference: nothing momentous about being maximal. World v y is a person, a maximal aggregate of personstages, and so has moral status. Possible Worlds World w So x, and all other personites, have moral status. World v y is a person, a maximal aggregate of personstages, and so has moral status. Why This is a Problem • If personites have moral status then there will be conflicts of interest between my personites and me and amongst innumerable personites. Unfair! WeTest: won’tearlier personites want one marshmallow now; • e.g. The Marshmallow be around to Delay gratification and even want 100 later personites want two later. Earlier personites wouldn’t enjoy it! save the best for last! marshmallows later because they won’t be around to enjoy them. I’m saving for retirement! • If I sacrifice pleasures now to save money so that I can enjoy a happy, financially secure retirement my earlier personites will bear the burden of my sacrifice but never get the pay-off since they won’t be around for my retirement. The Stage-Theoretical Response • Kaiserman argues that personites are not a problem for four-dimensionalism as such but only for the worm-theoretical version: the stage-theoretical version escapes this criticism. • According to the stage theory persons are instantaneous stages: neither maximal R-interrelated aggregates of stages, z and y, nor personite x, a non-maximal Rinterrelated aggregate of stages, is a person and has a past or future property in virtue of the fact that it is R-related to an earlier or later person-stage that has that property. • Premise 3 of the personite argument, ‘For all personites x, there are a possible object y and possible world v such that y is a person in v and y in v is a duplicate of x in the actual world, w’ is therefore false. (I’ve changed the letters in the argument to correspond to the example) Aggregates of Persons Don’t Have Moral Status • One might insist that…personites] are nevertheless duplicates of something with moral status, because maximal R-interrelated fusions of person-stages have moral status regardless of whether we decide to call them ‘people’. • But I don’t see why a stage theorist should accept this premiss. From the perspective of the stage theorist, the four-dimensional objects worm theorists call ‘people’ are no different from, say, the fusion of me and Mick Jagger (or, more to the point, the fusion of me and my modal counterparts). Why Should I Care? • If I’m just an instantaneous stage, why should I care about past or future states of affairs? • Because on any four-dimensionalist account, at any time, I have temporal properties, i.e. past and future properties having-been-F and going-to-be G in virtue of me being R-related to earlier and later stages that are F and G respectively. - E.g. I was in Alex Kaiserman’s class at Oxford 4 years ago in virtue being Rrelated to an earlier person-stage that was there. • ‘Self-interest’ is the concern a person has for stages that are R-related to them. - E.g. I want to have lunch 3 hours from now = I want R-related 3-hours-later stages to eat. The Moral Status of Person-Stages • Persons are instantaneous stages. • ‘Person is a forensic term’: persons, and only persons (human or otherwise) have moral status—i.e. they should be treated in certain ways, have their interests and desires respected, etc. • I have an interest in how things will go for me in the future, i.e., in how things go for later person-stages R-related to me, and if others trash those stages they set back my interests and harm me. • I’ll wait for that second marshmallow, save for retirement, etc. on this account because it’s in my interest that those later stages which are R-related to me get the marshmallows and cash in on the retirement fund. Objections and Replies Objection 1 • Even granting that I’m an instantaneous person-stage, there are innumerable other instantaneous things that occupy the same region but are different because they have different temporal properties in virtue of having different temporal counterparts. They’re intrinsic duplicates of me and so worthy of moral consideration (by Premise 2—intrinsic duplicates have same moral status). Competition again. • Response: Rather than admitting a multiplicity of entities with different temporal counterparts, the stage theorist should instead admit a multiplicity of counterpart relations…There is just one object coincident with me – me – but that object instantiates different temporal properties relative to different counterpart relations. Objection 2 • But now things look even worse for the stage theorist…[I]f facts about what I will do are relativized to a counterpart relation, it seems that facts about what it is practically rational for me to do now must also be relativized to a choice of counterpart relation…If it’s true of me that I ought to save for retirement, it’s true simpliciter, not simply true qua person. Mutatis mutandis for moral facts. • Response: Rather than relativizing moral and practical claims to a choice of temporal counterpart relation, the stage theorist should simply insist that there is a particular counterpart relation – the relation I’ve called R – such that what I ought…to do now depends on what will be true of me relative to that counterpart relation. The purpose of a theory of personal identity, as the stage theorist conceives of it, is precisely to figure out what this relation is…For that I need to know which relation is the one that matters. Conclusion [I]f personites turned out to be intrinsically identical to some (albeit merely possible) thing with moral status, it’s not clear on what rational grounds we could possibly resist the conclusion that they have moral status too. But this conclusion, if true, is disastrous – it’s incompatible with even our most basic intuitions about how to lead a minimally ethical and well-ordered life. In this paper, however, I have argued that although the personite problem is a problem for the worm theory, it does not affect the stage theory… [T]he stage theory is compatible with our basic ethical and prudential principles and the worm theory is not. So much the worse, then, for the worm theory.
