What is a temporal part? Most accounts explain it in terms of timeless parthood: a thing's having a part without temporal qualification. Some find this hard to understand, and thus find the view that persisting things have temporal parts--fourdimensionalism--unintelligible. T. Sider offers to help by defining temporal parthood in terms of a thing's having a part at a time. I argue that no such account can capture the notion of a temporal part that figures in orthodox four-dimensionalism: temporal parts must (...) be timeless parts. This enables us to state four-dimensionalism more clearly. (shrink)

Conjoined twinning is said to show that the number of human people—the number of us—can differ from the number of human organisms, and hence that we are not organisms. The paper shows that these arguments either assume the point at issue, rely on dubious and undefended assumptions, or add nothing to more familiar arguments for the same conclusion.

In this essay I explore the idea that the solution to some important problems of personal identity lies in the philosophy of language: more precisely in the nature of first-person reference. I will argue that the “linguistic solution” is at best partly successful.

Philosophers often talk as if what it takes for a person to persist through time were up to us, as individuals or as a linguistic community, to decide. In most ordinary situations it might be fully determinate whether someone has survived or perished: barring some unforeseen catastrophe, it is clear enough that you will still exist ten minutes from now, for example. But there is no shortage of actual and imaginary situations where it is not so clear whether one survives. (...) Here reasonable people may disagree. There are "fission" cases where each of one's cerebral hemispheres is transplanted into a different head; Star-Trek-style "teletransportation" stories; actual cases of brain damage so severe that one can never again regain consciousness, even though one's circulation, breathing, digestion, and other "animal" functions continue; and stories where one's brain cells are gradually removed and replaced by cells from someone else, to name only a few favorites. (shrink)

According to a view attractive to both metaphysicians and ethicists, every period in a person’s life is the life of a being just like that person except that it exists only during that period. These “subpeople” appear to have moral status, and their interests seem to clash with ours: though it may be in some person’s interests to sacrifice for tomorrow, it is not in the interests of a subperson coinciding with him only today, who will never benefit from it. (...) Or perhaps there is no clash, and a subperson’s interests derive from those of the person it coincides with. But this makes it likely that our own interests derive from those of other beings coinciding with us. (shrink)

While there has been considerable recent criticism of perdurance theory in connection with a Humean understanding of causality, perdurance theory conjoined with causal realism has received relatively little attention. One might, then, form the impression that perdurance theory under the auspices of causal realism is a relatively safe view. I shall argue, however, to the contrary. My general strategy is to show that there is no plausible way of spelling out the perdurance position (of the non-Humean, causal realist sort). I (...) implement this strategy by revealing several general problems concerning the causally-connected temporal parts scheme. I begin with a short account of perdurance theory. There follows a description of two general views of causality and the two subsequent accounts of the perduring object; then, the criticism. (shrink)

Eric Olson has argued, startlingly, that no coherent account can be giv- en of the distinction made in the personal identity literature between ‘complex views’ and ‘simple views’. ‘We tell our students,’ he writes, ‘that accounts of personal identity over time fall into [these] two broad categories’. But ‘it is impossible to characterize this distinction in any satisfactory way. The debate has been systematically misdescribed’. I argue, first, that, for all Olson has said, a recent account by Noonan provides the (...) coherent characterization he claims impossible. If so we have not been wrong all along in the way he says in what we have been telling our students. I then give an account of the distinction between the reductionist and non-reductionist positions which makes it differ- ent from the complex/simple distinction. The aim is to make clear sense of the notion of a not simple but non-reductionist position — which seems an eminently reasonable possibility and something it may also be useful to tell our students about. (shrink)

Jacob Ross argues that the fission cases discussed in the personal identity literature cannot be accommodated without rejecting basic intuitions of everyday ethical thinking. He notes that many philosophers have responded to the challenge of fission ‘by rejecting the metaphysical assumptions on which it rests’. In particular, that many have denied that in fission one ceases to exist. He contends that these denials do not meet the challenge to commonsense ethical thinking. I reject these claims. One of the metaphysical views (...) he considers is the multiple occupancy view of Lewis and Robinson, according to which in fission there are all along two numerically distinct, initially collocated, persons. I claim that Ross has not shown that this view has counterintuitive ethical implications. (shrink)

Different sort of people are interested in personal identity. Philosophers frequently ask what it takes to remain oneself. Caregivers imagine their patients’ experience. But both philosophers and caregivers think from the armchair: they can only make assumptions about what it would be like to wake up with massive bodily changes. Patients with a locked-in syndrome (LIS) suffer a full body paralysis without cognitive impairment. They can tell us what it is like. Forty-four chronic LIS patients and 20 age-matched healthy medical (...) professionals answered a 15-items questionnaire targeting: (A) global evaluation of identity, (B) body representation and (C) experienced meaning in life. In patients, selfreported identity was correlated with B and C. Patients differed with controls in C. These results suggest that the paralyzed body remains a strong component of patients’ experienced identity, that patients can adjust to objectives changes perceived as meaningful and that caregivers fail in predicting patients’ experience. (shrink)

Different sort of people are interested in personal identity. Philosophers frequently ask what it takes to remain oneself. Caregivers imagine their patients’ experience. But both philosophers and caregivers think from the armchair: they can only make assumptions about what it would be like to wake up with massive bodily changes. Patients with a locked-in syndrome suffer a full body paralysis without cognitive impairment. They can tell us what it is like. Forty-four chronic LIS patients and 20 age-matched healthy medical professionals (...) answered a 15-items questionnaire targeting: global evaluation of identity, body representation and experienced meaning in life. In patients, self-reported identity was correlated with B and C. Patients differed with controls in C. These results suggest that the paralyzed body remains a strong component of patients’ experienced identity, that patients can adjust to objectives changes perceived as meaningful and that caregivers fail in predicting patients’ experience. (shrink)

According to one argument for Animalism about personal identity, animal , but not person , is a Wigginsian substance concept—a concept that tells us what we are essentially. Person supposedly fails to be a substance concept because it is a functional concept that answers the question “what do we do?” without telling us what we are. Since person is not a substance concept, it cannot provide the criteria for our coming into or going out of existence; animal , on the (...) other hand, can provide such criteria. This argument has been defended by Eric Olson, among others. I argue that this line of reasoning fails to show Animalism to be superior to the Psychological Approach, for the following two reasons: (1) human animal , animal , and organism are all functional concepts, and (2) the distinction between what something is and what it does is illegitimate on the reading that the argument needs. (shrink)

I aim to show that, contrary to standard deflationary or eliminativist theories of the self, we can argue from the phenomenology of pre-reflective self-awareness for the thesis that subjects of experience are substances. The phenomenological datum of subjectivity points to a specific metaphysical structure of our experience, that is, towards the substance view rather than the bundle or the minimal self view. Drawing on modern philosophical accounts of pre-reflective self-awareness, mineness and (self-) acquaintance, I will argue that a subject is (...) aware of being the one individual who has many experiences and that it is revealed to the subject that it is the bearer of experiences and their unifier. The subject is present in pre-reflective awareness and known as the subject of experiences, and even this minimal self-awareness gives us reason to favour the substance view. Thus, one can demonstrate how the debates on the phenomenology of pre-reflective self-awareness and the metaphysics of selfhood intersect. (shrink)

I argue that perceptual content is always affected by the allocation of one’s attention. Perception attributes determinable and determinate properties to the perceived scene. Attention makes (or tries to make) our perceptual attribution of properties more determinate. Hence, a change in our attention changes the determinacy of the properties attributed to the perceived scene.

A radical metaphysical theory typically comes packaged with a semantic theory that reconciles those radical claims with common sense. The metaphysical theory says what things exist and what their natures are, while the semantic theory specifies, in terms of these things, how we are to interpret everyday language. Thus may we “think with the learned, and speak with the vulgar.” This semantic accommodation of common sense, however, can end up undermining the very theory it is designed to protect. This paper (...) is a case study, showing in detail how one popular version of temporal parts theory is self-undermining. This raises the specter that the problem generalizes to other metaphysical theories. (shrink)

Puzzles about persistence and change through time, i.e., about identity across time, have foundered on confusion about what it is for ‘two things’ to be have ‘the same thing’ at a time. This is most directly seen in the dispute over whether material objects can occupy exactly the same place at the same time. This paper defends the possibility of such coincidence against several arguments to the contrary. Distinguishing a temporally relative from an absolute sense of ‘the same’, we see (...) that the intuition, ‘this is only one thing’, and the dictum, ‘two things cannot occupy the same place at the same time’, are individuating things at a time rather than absolutely and are therefore compatible with coincidence. Several other objections philosophers have raised ride on this same ambiguity. Burke, originating what has become the most popular objection to coincidence, argues that if coincidence is possible there would be no explanation of how objects that are qualitatively the same at a time could belong to different sorts. But we can explain an object’s sort by appealing to its properties at other times. Burke’s argument to the contrary equivocates on different notions of ‘cross-time identity’ and ‘the statue’. From a largely negative series of arguments emerges a positive picture of what it means to say multiple things coincide and of why an object’s historical properties explain its sort rather than vice versa – in short, of how coincidence is possible. (shrink)

The fission of a person involves what common sense describes as a single person surviving as two distinct people. Thus, say most metaphysicians, this paradox shows us that common sense is inconsistent with the transitivity of identity. Lewis’s theory of overlapping persons, buttressed with tensed identity, gives us one way to reconcile the common sense claims. Lewis’s account, however, implausibly says that reference to a person about to undergo fission is ambiguous. A better way to reconcile the claims of common (...) sense, one that avoids this ambiguity, is to recognize branching persons, persons who have multiple pasts or futures. (shrink)

I demonstrate that the theory of persistence defended in Sider [2001] does not accommodate our intuitions about counting sentences. I develop two theories that improve on Sider's: a contextualist theory and an error theory. I argue that the latter is stronger, simpler, and better fitted to some important ordinary language judgments than rival four-dimensionalist theories of persistence.

ABSTRACT One simple but relatively neglected solution to the notorious coincidence puzzle of the statue and the piece of clay claims that the property of being a statue is a phase sortal property that the piece of clay instantiates temporarily. I defend this view against some standard objections, by reinforcing it with a novel counterpart-theoretic account of identity under a sortal. This proposal does not require colocation, four-dimensionalism, eliminativism, deflationism, or unorthodox theses about classical identity.

In this paper I take up the task, begun by Lewis and Lewis in their seminal paper on the topic, of offering a theory of holes according to which a hole is simply its hole-lining. I begin by motivating the theory, arguing that it holds interest even absent its original animating concerns of nominalism and materialism, and present desiderata any such theory must satisfy. With this in place, I offer a definition both of a lining and of hole sameness, arguing (...) that these can overcome the most prominent standing objections to identifying holes with linings. Finally, I present a more powerful counterargument in the spirit of Casati and Varzi, and conclude with an emended version of the theory meeting all our earlier desiderata. I conclude by dispelling some possible worries about the nominalist and materialist credentials of my theory. (shrink)

According to the Psychological Account of personal identity, personal identity across time is maintained by some form of psychological overlap or continuance. I show that the Psychological Account has trouble accommodating cases of transient retrograde amnesia. In such cases, the transitivity of psychological continuity may break down. I consider various means of responding to this problem, arguing that the best available response will undercut our ability to rely on intuitions about brain transplantation to support the Psychological Account. When the Psychological (...) Account is re-interpreted in such a way as to overcome the problems posed by cases of transient retrograde amnesia, it turns out that standard brain transplantation cases involve details which are strictly irrelevant according to the theory. On the other hand, these features seem to drive our intuitions about survival in these cases. In this way, my argument undermines one of the key motivations for adopting the Psychological Account. (shrink)

I argue that two competing accounts of persistence, three and four dimensionalism, are in fact metaphysically equivalent. I begin by clearly defining three and four dimensionalism, and then I show that the two theories are intertranslatable and equally simple. Through consideration of a number of different cases where intuitions about persistence are contradictory, I then go on to show that both theories describe these cases in the same manner. Further consideration of some empirical issues arising from the theory of special (...) relativity lead me to conclude that the two theories are equally explanatory, and thus finally that they are metaphysically equivalent. (shrink)

There is a fundamental ontological difference between two kinds of entity: things and objects. Unlike things, objects are not identical to any fusion of particulars. Unlike things, objects do not have mereological parts. While things are ontologically innocent, objects are not. Objects are meaty. I defend the distinction between things and objects, and provide an account of the nature of objects.

This paper defends a version of strong conventionalism minus the ontological commitments of that view. It defends the claim that strictly speaking there are no persons, whilst explicating how to make sense of talk that is about (or purportedly about) persons, by appealing to features in common to conventionalist accounts of personal identity. This view has the many benefits of conventionalist accounts in being flexible enough to deal with problem cases, whilst also avoiding the various worries associated with the existence (...) of both persons and human animals occupying the same place at the same time to which conventionalist accounts are committed. (shrink)

The doctrine of Microphysical Supervenience (MS) states that: Necessarily, if atoms A1 through An compose an object that exemplified intrinsic qualitative properties Q1 through Qn, then atoms like A1 through An (in all their respective intrinsic qualitative properties), related to one another by all the same restricted atom-to-atom relations as A1 through An, compose an object that exemplifies Q1 through Qn. I show that MS entails a contradiction and so must be rejected. And my argument against MS provides the resources (...) to show that Global Microphysical Supervenience (GMS) is false. GMS states that possible worlds qualitatively exactly alike at the microphysical level are qualitatively exactly alike at the macrophysical level. (shrink)

Good physical experiments conform to the basic methodological standards of experimental design: they are objective, reliable, and valid. But is this also true of thought experiments? Especially problems of personal identity have engendered hypothetical scenarios that are very distant from the actual world. These imagined situations have been conspicuously ineffective at resolving conflicting intuitions and deciding between the different accounts of personal identity. Using prominent examples from the literature, I argue that this is due to many of these thought experiments (...) not adhering to the methodological standards that guide experimental design in nearly all other disciplines. I also show how empirically unwarranted background assumptions about human physiology render some of the hypothetical scenarios that are employed in the debate about personal identity highly misleading. (shrink)

Both Marya Schechtman and Galen Strawson appeal to autobiographical memory in developing their accounts of personal identity. Although both scholars share a similar conception of autobiographical memory, they use it to develop theories of personal identity that are radically distinct. Memories that are relevant for personal identity are generally considered to be personal (autobiographical) memories of those events in one’s lifetime to which one can gain first-personal access: memories from-the-inside. Both Schechtman and Strawson base their discussion of personal identity on (...) exactly this type of memory. Empirical evidence shows, however, that personal memory imagery is not only visualised from-the-inside, from a “field” perspective. Personal memories may also involve “observer” perspectives, in which one sees oneself from-the-outside in the remembered scene. Both Schechtman and Strawson appeal to the notion of remembering from-the-inside, but they remain silent on the phenomenon of observer perspectives in personal memory. I suggest that accounts of personal identity that appeal to memory should consider observer perspectives as one aspect of personal memory. I explore the implications that the acknowledgment and inclusion of observer perspectives would have for both Schechtman’s and Strawson’s accounts. Even though autobiographical memory is not their theoretical target, both Schechtman and Strawson base their accounts of personal identity on their understanding of autobiographical memory. Therefore, their depictions of the nature of personal identity are founded upon an incomplete picture of autobiographical memory. (shrink)

What really matters fundamentally in survival? That question—the one on which I focus—is not about what should matter or about metaphysics. Rather, it is a factual question the answer to which can be determined, if at all, only empirically. I argue that the answer to it is that in the case of many people it is not one’s own persistence, but continuing in ways that may involve one’s own cessation that really matters fundamentally in survival. Call this the surprising result. (...) What are we to make of it? According to several philosophers, not much. I argue that these philosophers are wrong. What best explains the surprising result is that in the case of many people one’s special concern for oneself in the future is not fundamental, but derived. I explain what this means. Finally I explain why the task of explaining empirically what matters fundamentally in survival is in some ways more like a meditative quest than a traditional inquiry in western philosophy or social science and, as such, is best answered not by psychologists, but by philosophers. (shrink)

Leibniz’s Law (or as it sometimes called, ‘the Indiscerniblity of Identicals’) is a widely accepted principle governing the notion of numerical identity. The principle states that if a is identical to b, then any property had by a is also had by b. Leibniz’s Law may seem like a trivial principle, but its apparent consequences are far from trivial. The law has been utilised in a wide range of arguments in metaphysics, many leading to substantive and controversial conclusions. This article (...) discusses the applications of Leibniz’s Law to arguments in metaphysics. It begins by presenting a variety of central arguments in metaphysics which appeal to the law. The article then proceeds to discuss a range of strategies that can be drawn upon in resisting an argument by Leibniz’s Law. These strategies divide into three categories: (i) denying Leibniz’s Law; (ii) denying that the argument in question involves a genuine application of the law; and (iii) denying that the argument’s premises are true. Strategies falling under each of these three categories are discussed in turn. (shrink)

The advantages and risks of a number of new genome modifying procedures seeking to create healthy or enhanced individuals, such as Maternal Spindle Transfer, Pronuclear Transfer, Cytoplasmic Transfer and Genome Editing, are currently being assessed from an ethical perspective, by national and international policy organizations. One important aspect being examined concerns the effects of these procedures on different kinds of identity. In other words, whether or not a procedure only modifies the qualities or properties of an existing human being, meaning (...) that merely the qualitative identity of this single individual is affected, or whether a procedure results in the creation of a new individual, meaning that a numerically distinct human being would have come into existence. In this article, the different identity arguments proposed, so far, are presented with respect to these novel reproductive procedures. An alternative view is then developed using the Origin Essentialism argument to indicate that any cha... (shrink)

Plausible assumptions from Cosmology and Statistical Mechanics entail that it is overwhelmingly likely that there will be exact duplicates of us in the distant future long after our deaths. Call such persons “Boltzmann duplicates,” after the great pioneer of Statistical Mechanics. In this paper, I argue that if survival of death is possible at all, then we almost surely will survive our deaths because there almost surely will be Boltzmann duplicates of us in the distant future that stand in appropriate (...) relations to us to guarantee our survival. (shrink)

The central argument for animalism is the thinking animal problem : if you are not an animal, there are two thinkers within the region you occupy, i.e., you and your animal body. This is absurd. So you are an animal. The main objection to this argument is the thinking brain problem : animalism faces a problem that is structurally analogous to TAP. Specifically, if animalism is true, you and your brain both think. This is absurd. So animalism is false. The (...) purpose of this paper is to propose strategies animalists can endorse to solve TBP. I first show that animalists can solve TBP by arguing that it is not sound. This solution to TBP raises questions about personal identity over time and the mereological relation between the person and the brain. I argue that animalists can answer the personal identity question by endorsing non-biological persistence conditions as well as biological ones. For the mereological question, I first show that animalism is incompatible with four-dimensionalism and eliminativism. I then argue that animalists should endorse the dominant sortal account to answer the mereological question. (shrink)

It is widely assumed in psychology, philosophy, and linguistics that we count by identity. For example, to count the dogs by identity, we correlate each dog that isn't identical to the rest with a natural number, starting with one and assigning each successive dog the successive natural number. When we run out of distinct dogs, we've yielded a correct count. I argue that this model of counting is incorrect. We do not count by identity.

David Lewis argues that centered worlds give us a way to capture de se, or self-locating, contents in philosophy of language and philosophy of mind. In recent years, centered worlds have also gained other uses in areas ranging widely from metaphysics to ethics. In this paper, I raise a problem for centered worlds and discuss the costs and benefits of different solutions. My investigation into the nature of centered worlds brings out potentially problematic implicit commitments of the theories that employ (...) them. In addition, my investigation shows that the conception of centered worlds widely attributed to David Lewis is not only problematic, but in fact not his. (shrink)

Everettian accounts of quantum mechanics entail that people branch; every possible result of a measurement actually occurs, and I have one successor for each result. Is there room for probability in such an account? The prima facie answer is no; there are no ontic chances here, and no ignorance about what will happen. But since any adequate quantum mechanical theory must make probabilistic predictions, much recent philosophical labor has gone into trying to construct an account of probability for branching selves. (...) One popular strategy involves arguing that branching selves introduce a new kind of subjective uncertainty. I argue here that the variants of this strategy in the literature all fail, either because the uncertainty is spurious, or because it is in the wrong place to yield probabilistic predictions. I conclude that uncertainty cannot be the ground for probability in Everettian quantum mechanics. (shrink)

In a recent article, Caterina Moruzzi (2018) develops and defends her musical stage theory. This discussion response supposes that Moruzzi's development and def.

David Lewis’ contemplations regarding divine foreknowledge and free will, along with some of his other more substantial work on modal realism and his counterpart theory can serve as a springboard to a novel solution to the foreknowledge and metaphysical freedom puzzle, namely a proposal that genuine metaphysical freedom is compatible with determinism, which is quite different from the usual compatibilist focus on the compatibility between determinism and moral responsibility. This paper argues that while Lewis opens the doors to such a (...) possibility, in order to fully elucidate a genuinely metaphysical compatibilist account, Lewis’ own counterpart theory must be abandoned in favour of an account of trans-world identity that is theoretically framed by a modified version of Robert Nozick’s closest continuer theory. (shrink)

Advocates of occasional identity have two ways of interpreting putative cases of fission and fusion. One way—we call it the Creative view—takes fission to involve an object really dividing (or being replicated), thereby creating objects which would not otherwise have existed. The more ontologically parsimonious way takes fission to involve merely the ‘separation’ of objects that were identical before: strictly speaking, no object actually divides or is replicated, no new objects are created. In this paper we recommend the Creative approach (...) as the best way of dealing with certain problem cases involving teletransportation. Our considerations yield novel takes on psychological-continuity theories of personal identity and survival, and on the puzzle of Theseus' ship. (shrink)

Jim Stone argues that one cannot combine three-dimensionalism with counterpart theory. This paper argues to the contrary.

David Lewis's cohabitation theory suffered damaging criticism from Derek Parfit. Though many have defended versions of Lewis's theory Parfit's criticism has not been answered. This paper shows how to defend the cohabitation theory against Parfit's criticism.

The cohabitation theory is a popular solution to the problem of personal fission. It affirms that all the people who result from fission were there cohabiting the pre-fission body all along. Adopting this solution is an uncontroversial move for four-dimensionalists, but is it open to three-dimensionalists too? Some have thought so, but Katherine Hawley, Mark Johnston, and Eric Olson have argued to the contrary. They claim three-dimensionalists simply cannot be cohabitation theorists. In this paper, I explain how they can.