Eric T. Olson

E. J. Lowe and others argue that there can be 'uncountable' things admitting of no numerical description. This implies that there can be something without there being at least one such thing, and that things can be identical without being one or nonidentical without being two. The clearest putative example of uncountable things is portions of homogeneous stuff or 'gunk'. The paper argues that there is a number of portions of gunk if there is any gunk at all, and that the possibility of uncountable things is inadequately supported.

Suppose a certain man, Dion, has his foot amputated, and lives to tell the tale. That tale involves a well-known metaphysical puzzle, for most of us assume that there was, before the operation, an object made up of all of Dion’s parts except those that overlapped with his foot-- ”all of Dion except for his foot”, we might say, or Dion’s “foot-complement”. Call that object Theon. (Anyone who doubts that there is such a thing as Dion’s undetached foot-complement may imagine that ‘Theon’ is a name for Dion’s undetached head. Surely there is such a thing as Dion’s head? And surely Dion could, in principle, survive if his head were detached from the rest of him and kept alive?) It seems obvious that Theon, like Dion, continues to exist after the operation, for you cannot destroy an object merely by changing its surroundings--merely by removing something that was never a part of it. The puzzle, then (which might be called the problem of undetached parts), is how Dion and Theon are related after the operation. The most common answer to this question is that Dion and Theon come to occupy just the same region of space and to be made of just the same matter after the operation. The next-mostpopular answer is that Dion and Theon are made up of temporal parts, and while those of their temporal parts that “occur” before the operation only partly overlap, Dion and Theon have the very same post-operative temporal parts. Much as two roads can merge and have spatial parts in common, Dion and Theon merge and have temporal parts in common. Less popular accounts of the relation between Dion and Theon involve relativizing identity to concepts or times, and denying that there is such a thing as Theon. Michael Burke has recently proposed an intriguing new solution (or resurrected an ancient one) to the problem of undetached parts. [1] He argues that, despite appearances, Theon-- Dion’s foot-complement--ceases to exist when Dion’s foot is removed..

One of the main problems of personal identity is supposed to be how we relate to our bodies. A few philosophers endorse what is called a 'bodily criterion of personal identity': they say that we are our bodies, or at any rate that our identity over time consists in the identity of our bodies. Many more deny this--typically on the grounds that we can imagine ourselves coming apart from our bodies. But both sides agree that the bodily criterion is an important view which anyone thinking about personal identity must consider.

Constitutionalism says that qualitatively different objects can be made of the same matter at once. Critics claim that we should expect such objects to be qualitatively indistinguishable. E.J. Lowe thinks this complaint is based on the false assumption that differences in the way things are at a time must always be grounded in how things are at that time, and that we can answer it by pointing out that different kinds of coinciding objects are subject to different composition principles. I argue that he is mistaken on both counts

The paper concerns the metaphysical possibility of life after death. It argues that the existence of a psychological duplicate is insufficient for resurrection, even if psychological continuity suffices for personal identity. That is because our persistence requires immanent causation. There are at most three ways of having life after death: if we are immaterial souls; if we are snatched bodily from our deathbeds; or if there is immanent causation ‘at a distance’ as Zimmerman proposes--but this requires an ontology of temporal parts.

Many philosophers say that two or more people or thinking beings could share a single human being in a split‐personality case, if only the personalities were sufficiently independent and individually well integrated. I argue that this view is incompatible with our being material things, and conclude that there could never be two or more people in a split‐personality case. This refutes the view, almost universally held, that facts about mental unity and disunity determine how many people there are. I suggest that the number of human people is simply the number of appropriately endowed human animals.

This article concerns the claim that it is possible to create living organisms, not merely models that represent organisms, simply by programming computers. I ask what sort of things these computer-generated organisms are supposed to be. I consider four possible answers to this question: The organisms are abstract complexes of pure information; they are material objects made of bits of computer hardware; they are physical processes going on inside the computer; and they are denizens of an entire artificial world, different from our own, that the programmer creates. I argue that could not be right, that collapses into, and that would make strong alife either absurd or uninteresting. Thus, "virtual" strong alife amounts to the claim that, by programming a computer, one can literally bring bits of its hardware to life

The extended-mind thesis says that mental states can extend beyond one’s skin. Clark and Chalmers infer from this that the subjects of such states also extend beyond their skin: the extended-self thesis. The paper asks what exactly the extended-self thesis says, whether it really does follow from the extended-mind thesis, and what it would mean if it were true. It concludes that the extended-self thesis is unattractive, and does not follow from the extended mind unless thinking beings are literally bundles of mental states

From the time of Locke, discussions of personal identity have often ignored the question of our basic metaphysical nature: whether we human people are biological organisms, spatial or temporal parts of organisms, bundles of perceptions, or what have you. The result of this neglect has been centuries of wild proposals and clashing intuitions. What Are We? is the first general study of this important question. It beings by explaining what the question means and how it differs from others, such as questions of personal identity and the mind-body problem. It then examines in some depth the main possible accounts of our metaphysical nature, detailing both their theoretical virtues and the often grave difficulties they face. The book does not endorse any particular account of what we are, but argues that the matter turns on more general issues in the ontology of material things. If composition is universal--if any material things whatever make up something bigger--then we are temporal parts of organisms. If things never compose anything bigger, so that there are only mereological simples, then we too are simples--perhaps the immaterial substances of Descartes--or else we do not exist at all (a view Olson takes very seriously). The intermediate view that some things compose bigger things and others do not leads almost inevitably to the conclusion that we are organisms. So we can discover what we are by working out when composition occurs.

That grass is green, that pigs don’t fly, and that you are now awake are all hard facts. But there is often said to be something soft about matters of identity over time. Is today’s village church the very church that was first built here, despite centuries of repairs and alterations? How many parts of my bicycle do I need to replace before I get a numerically different bike? If a club disbands and years later some of the original members start a similar club with the same name, have we got two clubs, or one club with a discontinuous history? It is tempting to say that there are no hard answers to these questions laid up in heaven. There is no determinate fact of the matter. Those who disagree about such things are arguing about words, not facts. We are free to say what we like.

The prosaic content of these sayings is that events change from future to present and from present to past. Your next birthday is in the future, but with the passage of time it draws nearer and nearer until it is present. 24 hours later it will be in the past, and then lapse forever deeper into history. And things get older: even if they don’t wear out or lose their hair or change in any other way, their chronological age is always increasing. These changes are universal and inescapable: no event could ever fail to be first future, then present, then past, and no persisting thing can avoid growing older. We call this process time’s passage.

Many philosophers say that the same atoms may compose at once a statue and a lump of matter that could outlive the statue. I reject this because no difference between the statue and the lump could explain why they have different persistence conditions. But if we say that the lump is the statue, it is difficult to see how there could be any human beings. I argue that this and analogous problems about material objects admit only of solutions that at least appear to be radically at odds with our ordinary thinking.