It is intuitive to suppose that the question of whether I persist through a given period will always have a metaphysically substantive ‘yes’ or ‘no’ answer. Derek Parfit challenges this intuition. Given the truth of Reductionism, he argues, identity can be indeterminate. The main argument Parfit marshals in support of this claim employs his Sorites-style Combined Spectrum thought experiment. Despite its influence, there are conspicuous gaps in his argument. Notably, he claims that identity is indeterminate when questions about persistence are (...) ‘empty’. But indeterminacy in Sorites puzzles is traditionally held to result from vagueness – a topic Parfit avoids. Without an account of the relationships between vagueness, indeterminacy, and question-emptiness, his argument remains incomplete. I begin by outlining Parfit’s argument as it stands. I then propose that we can provide the missing details by supplementing Parfit’s treatment of the Combined Spectrum with Sider’s notion of nonsubstantivity. This gives us a clearer understanding of Parfit’s indeterminacy claim, and affords the room to accommodate vagueness in his argument. Once we spell out what this means, however, it becomes clear that a more radical conclusion is justified by Parfit’s reasoning: it is always an empty question whether a person persists. (shrink)

Derek Parfit famously defends a number of surprising views about "fission." One is that, in such a scenario, it is indeterminate whether I have survived or not. Another is that the fission case shows that it does not matter, in itself, whether I survive or not. Most critics of the first view contend that fission makes me cease to exist. Most opponents of the second view contend that fission does not preserve everything that matters in ordinary survival. In this paper (...) I shall provide a critique that does not rely on either of these contentions. There are other, interrelated reasons to reject Parfit's defense of the two theses. In particular, the availability of the following view creates trouble for Parfit: I determinately survive fission, but it is indeterminate which fission product I am. (shrink)

Derek Parfit’s argument against the platitude that identity is what matters in survival does not work given his intended reading of the platitude, namely, that what matters in survival to some future time is being identical with someone who is alive at that time. I develop Parfit’s argument so that it works against the platitude on this intended reading.

Derek Parfit argues that fission is prudentially better for you than ordinary death. But is having more fission products with good lives prudentially better for you than having just one? In this paper, we argue that it is. We argue that, if your brain is split and the halves are transplanted into two recipients, then it is prudentially better for you if both transplants succeed than if only one of them does. This upshot rules out, among other things, that the (...) prudential value of standing in the relation that matters in survival to multiple people is equal to their average well-being. (shrink)

According to Parfit’s assessment of fission, the fissioner can have prudential concern for each of the post-fission people and that concern will be rational in virtue of some relation he bears to those post-fission people. Parfit suggests that it is plausible that the relation that grounds rational prudential concern is not identity, but some other relation. This argument can be challenged by reference to Velleman’s account of anticipating having an experience on the reasonable assumption that prudential concern with respect to (...) a person P consists, in part, in the ability to anticipate having certain experiences of P. According to Velleman, the fissioner cannot anticipate having the experiences of the fission products. In this paper, I suggest, first, that even if we accept Velleman’s account of anticipating having an experience, there are variants of fission in which his account is satisfied and, second, that his account may have the implication that prudential concern does not require anticipatory concern. (shrink)

Given reductionism about people, personal persistence must fundamentally consist in some kind of impersonal continuity relation. Typically, these continuity relations can hold from one to many. And, if they can, the analysis of personal persistence must include a non-branching clause to avoid non-transitive identities or multiple occupancy. It is far from obvious, however, what form this clause should take. This paper argues that previous accounts are inadequate and develops a new proposal.

According to the Psychological-Continuity Account of What Matters, you are justified in having special concern for the well-being of a person at a future time if and only if that person will be psychologically continuous with you as you are now. On some versions of the account, the psychological continuity is required be temporally ordered, whereas, on other versions, it is allowed to be temporally unordered. In this paper, I argue that the account is implausible if the psychological continuity is (...) allowed to be temporally unordered. I also argue that, if the psychological continuity is required to be temporally ordered, it cannot plausibly be purely psychological (in the sense that the psychological continuity is not required to be caused through spatio-temporal continuity of a brain). The upshot is that no plausible version of the Psychological-Continuity Account of What Matters is purely psychological. So psychological continuity is not what matters in survival. (shrink)

Derek Parfit has offered numerous arguments in an attempt to establish that identity is not what matters. Jens Johannson has recently argued that Parfit's various arguments for the claim that identity is not what matters fail to establish what Parfit takes such arguments to establish. Johannson contends that this is due in part to the invalidity of one of Parfit's key arguments, and the fact that Parfit ignores a position that is compatible with the conclusions of his successful arguments and (...) the claim that identity is in fact what matters, namely, that I survive fission as either one of the fission products or the other, but it is indeterminate which one I survive as. I aim to establish here that both of Johannson's assertions are problematic. As a corollary of this task, I hope to shed some light on the relationship between indeterminacy and fission-based arguments for the claim that identity is not what matters. (shrink)

The rare condition known as dicephalus occurs when (prior to implantation) a zygote fails to divide completely, resulting in twins who are conjoined below the neck. Human dicephalic twins look like a two-headed person, with each brain supporting a distinct mental life. Jeff McMahan has recently argued that, because they instance two of us but only one animal, dicephalic twins provide a counterexample to the animalist's claim that each of us is identical with a human animal. To the contrary, I (...) argue that in cases of dicephalus it is obvious neither that there is one animal nor that there are two of us. Consequently, the animalist criterion does not straightforwardly apply to cases of dicephalus. I defend an account of dicephalus that is both sensitive to the complexity of twinning phenomena and not inconsistent with animalism. In my view, dicephalic twins are a borderline case of the concept HUMAN ANIMAL. I conclude with some speculative remarks concerning the normative import (if any) of my claim that dicephalic twins are a borderline case. (shrink)

Traditionally, this puzzle has been solved in various ways. Aristotle, for example, distinguished between “accidental” and “essential” changes. Accidental changes are ones that don't result in a change in an objects' identity after the change, such as when a house is painted, or one's hair turns gray, etc. Aristotle thought of these as changes in the accidental properties of a thing. Essential changes, by contrast, are those which don't preserve the identity of the object when it changes, such as when (...) a house burns to the ground and becomes ashes, or when someone dies. Armed with these distinctions, Aristotle would then say that, in the case of accidental changes, (1) and (2) are both false—a changing thing can really change one of its “accidental properties” and yet literally remain one and the same thing before and after the change. (shrink)

The thesis of this paper is that – in order to avoid trivializations – a Philosophy of Birth needs to elaborate a precise concept of transformation and distinguish it carefully from that of adaptation. While transformation goes beyond the limited self-referential perspective of an individual and, on the social level, of the gregarious identity, adaptation aims at strengthening or preserving the old self-referential equilibrium. Transformation is driven by what Zambrano has called, with an exceptionally happy expression, the “hunger to be (...) born completely”. Such a hunger pushes one to continue one’s own birth through the encounter with the Other. Transformation has a creative feature that is made possible by two factors: the surplus of the effect over the cause, and the priority of the real over the possible. These premises lead to a radical questioning of the primacy of the possible on the real, at least as it has been conceived so far in mainstream Western philosophy, with few exceptions, such as Schelling, Bergson and Scheler. In the first part of this text, I shall consider a new Philosophy of Birth in the light of the concept of transformation and in this regard deal with several core themes such as the hunger to be born completely, the new beginning, creative time, the priority of the real over the possible, the limits of finalism, the surplus of effect over cause, and the creative force that expresses itself in the act of ideation. In the second part, I shall analyze the relation between birth and death and focus especially on their intimate and reciprocal connection by referring to the image of the seed that, after falling on the ground, germinates and breaks its own integument. (shrink)