The Ontological Basis of Strong Artificial Life

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

Composition and Coincidence

[First Paragraph] 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. 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

Was Jekyll Hyde?

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

There is No Problem of the Self

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

Personal identity and the radiation argument

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

The Ontology of Material Objects

[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

An Argument for Animalism

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

Why I have no hands

[FIRST PARAGRAPH] Consider the following argument for the claim that there are no hands--or feet or ears or any other arbitrary parts of human beings. Premise One: I am the only rational, conscious being--for short, the only person-- now sitting in this chair. 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'. Premise Two: Anything that would be rational and conscious in one environment could not fail to be rational or conscious in another environment without differing internally in some way. Nothing can fail to be rational or conscious merely by having the wrong relational properties. All philosophers of mind except perhaps dualists and eliminative materialists make this assumption. The content of someone's intentional states might be sensitive to her surroundings: on Twin Earth there may be someone whose mind is just like yours except that your thoughts about water correspond in him or her to thoughts about something else, if the colourless, potable liquid called 'water' on Twin Earth is not H2O but a substance with a different chemical composition. But unless mental features are not caused by physical ones, that being could hardly fail to be rational or conscious at all, if you are rational and conscious. Premise Three: If there is such a thing as my hand, there is also such a thing as my "hand-complement": an object made up or composed of just those parts of me that don't share a part with my hand. [1] If my hand exists, then "the rest of me but for my hand" exists as well. (I assume that I am a material object, and that my hand, if it existed, would be a part of me.) 2 This is just to say that there is nothing ontologically special about hands: saying that there are hands but no hand-complements would be as arbitrary as saying that there are hands but no feet. Any reasonable ontology of material objects that gives us hands gives us hand-complements as well. This might sound less than obvious because 'hand' is a familiar, compact word of ordinary English, while 'handcomplement' is philosophical jargon. But that is an accidental feature of our language, and presumably reflects our interest in hands and our lack of interest in hand-complements. There is no reason to suppose that it has any ontological significance. Consider that 'cheir' in ancient Greek and 'manus' in Latin, the words that dictionaries translate as 'hand', actually meant something that included eight or ten inches of forearm. Strictly speaking, the ancient Greeks and Romans had no word for what we call hands. But that does not imply that they disagreed with us about what material objects there are

Animalism and the Corpse Problem

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

The paradox of increase

[FIRST PARAGRAPHS] 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. 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