Online research in philosophy

The metaphysics of personal identity is rarely approached in a systematic way. The usual practice is to start with a question such as what our identity over time consists in, and canvass our opinions about a range of fictional “test cases” (is it the same person?). The view that does best by those opinions is then taken to answer the question. Whether that view fits into any wider metaphysical picture is left open.

Animalism is the view that you and I are animals. That is, we are animals in the straightforward sense of having the property of being an animal, or in that each of us is identical to an animal-not merely in the derivative sense of having animal bodies, or of being "constituted by" animals. And by 'animal' I mean an organism of the animal kingdom." Sensible though it may appear, animalism is highly contentious. The most common objection is that it conflicts (...) with widespread and deep beliefs about our identity over time. These beliefs are brought out in reactions to fictional cases. Suppose, for instance, that your brain is transplanted into my head. The being who ends up with that organ, everyone assumes, will remember your life and not mine. More generally, he will have your beliefs, preferences, plans, and other mental properties, for the most part at least. Who would he be-you, me, or someone else? (shrink)

Is life after death metaphysically possible? What would have to be the case for us to have it? What are the necessary conditions for any possible afterlife? Let us suppose for the sake of argument that there is a being with all the tools of omnipotence at its disposal-God for short. What would he have to do to give us life after death? Or is there anything he could do?

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. (shrink)

The next item on the syllabus was the ~Re ublic, and here too it was the metaphysical claims that excited me. With the naive audacity of youth, I wrote an essay arguing that Plato's doctrine of the Forms couldn't possibly be right. (My teacher, as I recall, was unconvinced; but she was not a philosopher, and was unable to defend the doctrine against my objections.) The subject I had stumbled across was so much more fun than chemistry and mathematics that (...) before the year was out I had given up the career plans I had nursed since my adolescence and changed the focus of my studies to philosophy. (shrink)

This paper-written for nonspecialist readers-asks whether life after death is in any sense possible given the apparent fact that after we die our remains decay to the point where only randomly scattered atoms remain. The paper argues that this is possible only if our remains are not in fact dispersed in this way, and discusses how that might be the case.

Personal identity deals with the many philosophical questions about ourselves that arise by virtue of our being people. The most frequently discussed is what it takes for a person to persist through time. Many philosophers say that we persist by virtue of psychological continuity. Others say that our persistence is determined by brute physical facts, and psychology is irrelevant. In choosing among these answers we must consider not only what they imply about who is who in particular cases, both real (...) and imaginary, but also their implications about our metaphysical nature in general. (shrink)

What happens to us when we die, if there is no afterlife? We might cease to exist, or continue existing as corpses. The view that we become corpses is hard to defend, because it makes it hard to say what our identity over time could consist in. The view that we cease to exist is little better: it seems to imply that there are no such things as corpses. A satisfying metaphysics of death is elusive.

Suppose we take a pound of gold and mold it into the shape of Hermes. Then, it would seem, we shall have a golden statue of Hermes, beautiful to behold. We shall also have a lump of gold. And we have the makings of a well-known philosophical puzzle. Many people find it obvious that if we crushed the statue or melted it down, we should destroy the statue but not the lump of gold. The lump can be deformed and still (...) continue to exist, but the statue cannot; that is the nature of lumps and statues. So the lump can outlive the statue. Since nothing can outlive itself, it is natural to conclude that the one-pound gold statue and the one-pound lump of gold in our example are numerically different. And as statues are to lumps, they say, so are brick houses to heaps of bricks, living organisms to masses of matter, and people to their bodies. More generally, certain atoms (or elementary particles or what have you) often compose two numerically different material objects at once. To put it another way, two different material objects may have all the same proper parts (the same parts except themselves) at once. [1] Because of its many defenders and its intuitive attraction, I will call this the Popular View about lumps and statues and other familiar material objects. (shrink)

Was sind wir? Wie immer man sich zu dieser Frage stellt, eines scheint offenkundig: Wir sind Tiere, genauer gesagt: menschliche Tiere, Mitglieder der Art Homo sapiens. Dabei mag es überraschen, daß viele Philosophen diese vermeintlich banale Tatsache abstreiten. Plato, Augustinus, Descartes, Locke, Berkeley, Hume, Kant und Hegel, um nur einige herausragende zu nennen, waren alle der Meinung, wir seien keine Tiere. Es mag zwar sein, daß unsere Körper Tiere sind. Doch sind wir nicht mit unseren Körpern gleichzusetzen. Wir sind etwas (...) anderes als Tiere. Kaum anderer Meinung sind Denker nicht-westlicher Traditionen. Und rund neun von zehn Philosophen, die heutzutage über Probleme der personalen Identität nachdenken, vertreten Ansichten, die ausschließen, daß wir Tiere sind. (shrink)

For a long time philosophers thought material objects were unproblematic. Or nearly so. There may have been a problem about what a material object is: a substance, a bundle of tropes, a compound of substratum and universals, a collection of sense-data, or what have you. But once that was settled there were supposed to be no further metaphysical problems about material objects. This illusion has now largely been dispelled. No one can get a Ph.D. in philosophy nowadays without encountering the (...) puzzles of the ship of Theseus, the statue and the lump, the cat and its tail complement', amoebic fission, and others. These problems are especially pressing on the assumption that we ourselves are material objects. (shrink)

Having already written a formal review of Persons and Bodies Mind 110, 2001, 427-430), I see this exchange as a sort of tutorial. I will try to explain why I found certain parts of the book puzzling or implausible, and Professor Baker will try to set me straight.

This book consists of fifteen new essays and an introduction by Zimmerman. Most of the authors are Christian philosophers in the ‘analytic’ tradition, and the book is of particular interest to readers of that sort; but there is nothing here that will interest only Christians. As the title suggests, all the essays have at least something to do with persons as such, and most deal with metaphysical issues. Beyond that they are pretty disparate. Seven papers are on substance dualism or (...) idealism, which get a more sympathetic hearing than current fashion would dictate. Lynn Rudder Baker, Hud Hudson, and Peter van Inwagen discuss materialist accounts of human people that they have developed elsewhere. There are papers on specifically Christian doctrines--immortality, divine incarnation, the trinity, and original sin--and one on the value of human people by Philip Quinn. For better or worse, there is almost no discussion of the existence of God. Even so, no one can accuse the authors of avoiding the big questions and retreating to narrow, technical issues. There is as much at stake in these essays as there is in any work of Plato or Kant. (shrink)

If we are neither animals nor material things constituted by animals, we might be parts of animals. This chapter is devoted to the view that we are spatial parts of animals; the next asks whether we are temporal parts. The only spatial parts of animals that I can think of any reason to suppose we might be are brains, or something like brains--parts of brains or perhaps entire central nervous sytems. Call the view that we are something like brains the (...) brain view. (shrink)

Accounts of personal identity over time are supposed to fall into two broad categories: 'complex views' saying that our persistence consists in something else, and 'simple views' saying that it doesn' t. But it is impossible to characterize this distinction in any satisfactory way. The debate has been systematically misdescribed. After arguing for this claim, the paper says something about how the debate might be better characterized.

One of the big questions about death is what makes it bad. There is a busy industry devoted to this question, turning out answers and debating their merits. But the most famous response to it is that there is nothing bad about death. This view is traditionally associated with Epicurus, though whether he actually held it is doubtful. In any event, I will be concerned with the view and not the man.

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. (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)

The view that we are human animals, "animalism", is deeply unpopular. This paper explains what that claim says and why it is so contentious. It then argues that those who deny it face an awkward choice. They must either deny that there are any human animals, deny that human animals can think, or deny that we are the thinking things located where we are.

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. (shrink)

Many philosophers say that time involves a kind of passage that distinguishes it from space. A traditional objection is that this passage would have to occur at some rate, yet we cannot say what the rate would be. The paper argues that the real problem with time’s passage is different: time would have to pass at one second per second, yet this is not a rate of change. This appears to refute decisively not only the view that time passes, but (...) any tensed theory of time. (shrink)

This paper is about the neglected question of what sort of things we are metaphysically speaking. It is different from the mind-body problem and from familiar questions of personal identity. After explaining what the question means and how it differs from others, the paper tries to show how difficult it is to give a satisfying answer.

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. (shrink)

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. (shrink)

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—four-dimensionalism—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)

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. (shrink)

It seems evident that things sometimes get bigger by acquiring new parts. But there is an ancient argument purporting to show that this is impossible: the paradox of increase or growing argument.i Here is a sketch of the paradox. Suppose we have an object, A, and we want to make it bigger by adding a part, B. That is, we want to bring it about that A first lacks and then has B as a part. Imagine, then, that we conjoin (...) B to A in some appropriate way. Never mind what A and B are, or what this conjoining amounts to: let A be anything that can gain a part if anything can gain a part, and let B be the sort of thing that can become a part of A, and suppose we do whatever it would take to make B come to be a part of A if this is possible at all. Have we thereby made B a part of A? It seems not. We seem only to have brought it about that B is attached to A, like this. (shrink)

The apparent fact that each of us coincides with a thinking animal looks like a strong argument for our being animals (animalism). Some critics, however, claim that this sort of reasoning actually undermines animalism. According to them, the apparent fact that each human animal coincides with a thinking body that is not an animal is an equally strong argument for our not being animals. I argue that the critics' case fails for reasons that do not affect the case for animalism.

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. (shrink)

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. (shrink)

[First paragraph] For a long time philosophers thought material objects were unproblematic. Or nearly so. There may have been a problem about what a material object is: a substance, a bundle of tropes, a compound of substratum and universals, a collection of sense-data, or what have you. But once that was settled there were supposed to be no further metaphysical problems about material objects. This illusion has now largely been dispelled. No one can get a Ph.D. in philosophy nowadays (...) without encountering the puzzles of the ship of Theseus, the statue and the lump, the cat and its tail complement', amoebic fission, and others. These problems are especially pressing on the assumption that we ourselves are material objects. (shrink)

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.

Personal identity deals with questions about ourselves qua people (or persons). Many of these questions are familiar ones that occur to everyone at some time: What am I? When did I begin? What will happen to me when I die? Discussions of personal identity go right back to the origins of Western philosophy, and most major figures have had something to say about it. (There is also a rich literature on personal identity in Eastern philosophy, which I am not competent (...) to discuss. Collins 1982 is a good source.). (shrink)

Sydney Shoemaker argues that the functionalist theory of mind entails a psychological-continuity view of personal identity, as well as providing a defense of that view against a crucial objection. I show that his view has surprising consequences, e.g. that no organism could have mental properties and that a thing's mental properties fail to supervene even weakly on its microstructure and surroundings. I then argue that the view founders on "fission" cases and rules out our being material things. Functionalism tells us (...) little if anything about personal identity. (shrink)

Cartesian or substance dualism is the view that concrete substances come in two basic kinds. There are material things, such as biological organisms. These may be either simple or composed of parts. And there are immaterial things--minds or souls--which are always simple. No material thing depends for its existence on any soul, or vice versa. And only souls can think.

It is often said that the same particles can simultaneously make up two or more material objects that differ in kind and in their mental, biological, and other qualitative properties. Others wonder how objects made of the same parts in the same arrangement and surroundings could differ in these ways. I clarify this worry and show that attempts to dismiss or solve it miss its point. At most one can argue that it is a problem we can live with.

Sydney Shoemaker has argued that, because we can imagine a people who take themselves to survive a 'brain-state-transfer' procedure, cerebrum transplant, or the like, we ought to conclude that we could survive such a thing. I claim that the argument faces two objections, and can be defended only by depriving it any real interest.

In "Was I Ever a Fetus?" I argued that, since each of us was once an unthinking fetus, psychological continuity cannot be necessary for us to persist through time. Baker claims that the argument is invalid, and that both the premise and the conclusion are false. I attempt to defend argument, premise, and conclusion against her objections.

In this paper I shall explore a novel alternative to these familiar views. In his recent book Sub ects of Ex erience, E. J. Lowe argues, as many others have done before, that you and I are not animals. It follows from this, he says, that we must be simple substances without parts. That may sound like Cartesian dualism. But Lowe is no Cartesian. He argues from premises that many present-day materialists accept. And he claims that our being mereologically simple (...) is consistent with our having such paradigmatically physical properties as being six feet tall and weighing 160 pounds. You and I, he claims, are mereological atoms shaped like human beings. (shrink)

Because there is no agreed use of the term 'self', or characteristic features or even paradigm cases of selves, there is no idea of "the self" to figure in philosophical problems. The term leads to troubles otherwise avoidable; and because legitimate discussions under the heading of 'self' are really about other things, it is gratuitous. I propose that we stop speaking of selves.

This article concerns the claim that it is possible to create living organisms, not merely models that represent organisms, simply by programming computers ("virtual" strong alife). I ask what sort of things these computer-generated organisms are supposed to be (where are they, and what are they made of?). I consider four possible answers to this question: (a) The organisms are abstract complexes of pure information; (b) they are (...) material objects made of bits of computer hardware; (c) they are physical processes going on inside the computer; and (d) they are denizens of an entire artificial world, different from our own, that the programmer creates. I argue that (a) could not be right, that (c) collapses into (b), and that (d) 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. (shrink)

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.. (shrink)

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)

Most philosophers writing about personal identity in recent years claim that what it takes for us to persist through time is a matter of psychology. In this groundbreaking new book, Eric Olson argues that such approaches face daunting problems, and he defends in their place a radically non-psychological account of personal identity. He defines human beings as biological organisms, and claims that no psychological relation is either sufficient or necessary for an organism to persist. Olson rejects several famous thought-experiments dealing (...) with personal identity. He argues, instead, that one could survive the destruction of all of one's psychological contents and capabilities as long as the human organism remains alive--as long as its vital functions, such as breathing, circulation, and metabolism, continue. (shrink)

The Standard View of personal identity says that someone who exists now can exist at another time only if there is continuity of her mental contents or capacities. But no person is psychologically continuous with a fetus, for a fetus, at least early in its career, has no mental features at all. So the Standard View entails that no person was ever a fetus--contrary to the popular assumption that an unthinking fetus is a potential person. It is also mysterious what (...) does ordinarily happen to a human fetus, if it does not come to be a person. Although an extremely complex variant of the Standard View may allow one to persist without psychological continuity before one becomes a person but not afterwards, a far simpler solution is to accept a radically non-psychological account of our identity. (shrink)

Trust me: my chair isn't big enough for two. You may doubt that every rational, conscious being is a person; perhaps there are beings that mistakenly believe themselves to be people. If so, read ‘rational, conscious being’ or the like for 'person'.