There's a fun paper by David and Stephanie Lewis on this question. You can find it in the first volume of Lewis's Philosophical Papers or at this link .

You might look at Contemporary Debates in Metaphysics , edited by Ted Sider, John Hawthorne and Dean Zimmerman.

Here are two other sources: The Stanford Encyclopedia of Philosophy (http://plato.stanford.edu/): for helpful introductions and bibliographies on topics in all (or at least very many) areas of philosophy Dave Chalmers's "Mind Papers" (http://consc.net/mindpapers/): a compilation of papers in philosophy of mind and cognitive science

You might just as easily wonder how you know that other people do feel pain. Both questions are instances of what philosophers often call "the problem of other minds." I believe that other people have psychological states (thoughts, beliefs, sensations, etc.) and that things like rocks and plants do not. How do I know this? It seems on the face of it that I cannot know that someone (other than myself) is in pain in the same way that I can know that the table in front of me is brown; I cannot directly observe the pain of another person. So presumably I must know that someone is in pain on the basis of something I can observe: his or her behavior. I see a batter get hit by a pitch. He falls to the ground, grimaces and writhes around. From this behavior, I infer that the batter is in pain. In a similar vein, when a plant does not exhibit any of that kind of behavior (or anything that could be understood as behavior at all), I conclude that the plant does not feel pain (or anything else, for that...

Here's another thought experiment that philosophers sometimes appeal to in this context. Suppose someone invents a teleportation machine (like in Star Trek). The machine scans your body, vaporizes it, and then recreates a molecule for molecule duplicate somewhere on Mars. Would you survive this process? That is, would the person on Mars be the same person who stepped into the machine on earth? Or would you cease to exist, only to be replaced on Mars by someone who is exactly like you? If personal identity is just a matter of physical continuity, then you probably don't want mess around with teleportation.

You can find an interesting discussion of the definition of 'death' in Peter Singer's "Rethinking Life and Death." There is a helpful discussion in the first chapter about "The Ad Hoc Committee of the Harvard Medical School to Examine the Definition of Brain Death." This committee proposed in 1968 to "redefine" death so that a person who has suffered irreversible loss of all brain function counts as dead, even if the person is still breathing with the help of a respirator. While this proposal met with little resistance, people are much less inclined to say that someone in a persistent vegetative state is dead--even if there is an irreversible loss of consciousness.

We often use the verb "to see" in such a way that to say I see a cat is to imply that there's a cat in front of me (and that my eyes are open, etc.) In this way, my beliefs about what I see could be mistaken: I can believe that I see a cat, but I could be wrong if there is no cat there for me to see. It seems similarly odd to say that I feel pain, but there is no pain there for me to feel. The difference is that pains--unlike cats--are thought to be mind dependent. And many philosophers have thought that while we can be mistaken about the existence of things like cats, trees and tables, we cannot be mistaken about the contents of our own minds. For that reason, I can be wrong that I see a cat, but I cannot be wrong that I feel pain. Sometimes we use the word "see" in a way that does not imply that there is an object there in front of our eyes. I could describe a dream by saying, "I saw an elephant coming toward me." Since I was dreaming, there was no elephant there for me to see. But it...

How about Elizabeth Anscombe? Here's an interesting obituary in the Guardian (she died in 2001): http://www.guardian.co.uk/Archive/Article/0,4273,4115443,00.html

There are a number of argumentative moves that philosophers typically make, and you will become familiar with them as you read and write more philosophy. You can find examples of these moves in Jim Pryor's guidelines on reading philosophy and writing philosophy papers: http://www.jimpryor.net/teaching/guidelines/reading.html http://www.jimpryor.net/teaching/guidelines/writing.html

You might be interested in this 2001 article by Peter Singer (author of Animal Liberation): http://www.nerve.com/Opinions/Singer/heavyPetting/