Regarding the age old conundrum of the tree falling in the forest. According to Barclay, there is no sound if there is no mind to hear it. I am thinking that there may be no human around hence no human auditory organs to absorb the waves and send the message of "sound" to the brain.....but that is a bit anthropocentric. The forest is full of creatures that have auditory organs, so some brains will hear the sound....some minds will perceive the sound of a crashing tree, no? (listening to Nigel Warburton's A Little History of Philisophy)

I agree. I don't know what Berkeley says about whether any nonhuman animals possess minds, but on his view, I take it, nonhuman animals would need to possess minds in order to perceive anything. Indeed, according to Berkeley, not only does the tree make no sound unless a mind perceives the sound, but the tree doesn't even exist without a mind to perceive it. (Even if no finite mind perceives the tree, Berkeley attributes the tree's existence to the tree's being perceived by God's mind.) Notice, too, that if we construe "a sound" dispositionally, i.e., as simply a disturbance that would be heard if there were a normally equipped listener to hear it, then sounds can occur even with no listeners (human or nonhuman) on the scene.

Person A receives a large amount of money. Being selfless, he doesn't want to keep the money and sends it to person B. Unfortunately, B is also selfless, and sends the money back to A. A then sends the money to C. Fortunately, C is selfish and keeps the money. Can there be selflessness without there being selfishness?

I think so. Consider the example you gave. A's selflessness (her generosity, anyway) is manifested by her sending the money to B, whether or not B ends up accepting the money. Now, if A somehow knows that B will return the money immediately and is counting on B to return it, then A's selflessness is only apparent rather than genuine. But otherwise, I see no reason why A's action can't be considered genuinely selfless, whether or not the recipient in fact keeps the money. Further, I see no reason why C must be deemed selfish just because he accepts the money: it might be that, through no fault of his own, C desperately needs the money. What I think genuine selflessness does require is scarcity: if a particular resource is available to all in unlimited supply, then no one can genuinely make a gift of that resource, let alone a selfless gift. So I don't think there can be selflessness in heaven, if heaven is as it's described by various religions.

how many branches of philosophy are there, and why is language picked apart so meticulosly?

At least 33, to judge from the Areas of Specialization (AOS) listed here: Less facetiously: There's no non-arbitrary way to give a precise answer to your question, just as with the question "How many branches of science are there?" Careful attention to language is essential because, among other things, only when we're careful about language can we tell which philosophical problem (if any) we're trying to solve or which philosophical question (if any) we're trying to answer.

I've been wrestling with this problem for some time. My question concerns the concept of 'possibility'. When one says that something is possible, they are saying that something might be but may not be as well. There is an uncertainty. And of course whatever it is cannot both be and not be at the same time. Now, when we say that something is 'not possible', we are saying that something is not and cannot be. There is no uncertainty and the term as used does not seem to be a true negation as is usually meant when the term 'not' is used. What confuses me, is that in when actually trying to negate the concept of possibility, such as when saying 'not possible', aren't we on the one hand saying that 'that which might be' is not, and on the other hand that 'that which may not be' is not as well, and therefore is (or could be)? What may be is not and/or what may not be is. Saying that something is not possible, in this sense, is the same as saying that it is possible, thus making the negation of the concept...

I don't think there's a deep puzzle here, as I hope I can explain. The kind of possibility that stems from uncertainty is usually called "epistemic possibility," often signaled in English by "may" or "might," as in "There may [or might] be life on other planets." We're far from certain that there isn't life on other planets, so there may [for all we know] be life on other planets: life on other planets is an epistemic possibility for us. There are other kinds of possibility, such as metaphysical possibility, but I think the general point I'll make applies to all of them. To deny possibility in this sense, to say that some state of affairs S isn't epistemically possible for someone, is roughly to say that he/she is certain that S doesn't obtain, or at least he/she knows that S doesn't obtain (if knowledge doesn't require certainty). So I'd say that, right now, my own non-existence is epistemically impossible for me, because I know (indeed, I'm certain) that I exist, for the reason Descartes gives...

The general consensus seems to be that since men aren't women, they can't speak about or fully understand the issues pertaining to women. I once read an analogy that tried to equate this logic with someone telling a veterinarian that since he isn't a cat, he cannot speak about the issues pertaining to cats. But since veterinarians do speak about cat issues, then it is safe to assume that men can speak about women's issues as well. Does the analogy work? Can men speak about women's issues?

To start with the literal truth: Men can indeed speak about issues pertaining to women, because (some) men do speak about such issues, which proves that they can . The question is how authoritative, how credible, about those issues a man can be. I think that will depend on the issue. An appropriately trained male researcher can speak with authority about (for example) the long-term health effects of this or that means of female contraception. But if the issue is more "experiential" or "phenomenological" -- such as "What does it feel like to be a female victim of workplace sexual harassment?" -- then it seems clear that any male has at least a burden of proof to discharge before we should regard his statements as authoritative or credible. I'm not saying that this burden can't possibly be discharged, only that it exists. (Clearly, I assume that speaking credibly about whether a man can be authoritative on issue X doesn't require me to be an authority on issue X itself.) For my answer to a...

Could I have come into existence and experienced my "self" if my ancestors had not been the same persons, or if a different sperm cell had coupled with my mothers egg? Would my "I" then have remained unborn or been born to a different body, maybe at a different time, or my vacancy occupied by a different persons "I"? In order for a particular "I" to be realized, must it have existed as a potential beforehand, like a lottery tickets potential for winning? Evolution and probability theory indicate that the chances for any particular individual to exist is practically zero. Have we who exist been incredibly lucky, or can our "I" be realized in some other being? If so, on what grounds is the particular potential self assigned to a particular body. I have explored several philosophical texts hoping to find something about this topic, but without success. I would be very glad if you could comment on it or direct me to some illuminating textbook or other source.

Your questions touch on several interesting and difficult issues. If you haven't already consulted it, I recommend looking at the SEP entry on "Possible Objects" . It's a somewhat challenging read, but it contains discussion (for example, in Section 2.2) of the issues you raised, and (as usual for the SEP) copious references that you can follow up. Best of luck as you grapple with this topic!

Premise 1: If God does not exist, objective moral values and duties do not exist. Premise 2: Objective moral values and duties do exist. Conclusion: Therefore, God exists. Can we accept the conclusion above as valid or even fact?

The argument itself is logically valid -- indeed, formally valid. It uses only modus tollens and the rule that "P" and "~ ~ P" are equivalent, both of which are valid rules of inference. However, I think the argument is unsound -- and therefore I think it fails to establish its conclusion -- because Premise 1 is false, at least if Premise 1 is meant as a strict conditional. (I think it's also false if it's meant as a material conditional, but that's more controversial.) For excellent discussion of Premise 1, I recommend this article and this collection of essays .

My question is on death. I am young and have read a lot. A few people have passed in my short lived life and death is an interesting topic for me. Many people believe death is not the end, they say it is the beginning of life. How can it be the beginning if you are dead? Your body is dead I believe, but the soul lives forever even if it rotts in hell. Many claim they are not afraid of death. I think its true death is nothing to be afraid of. What we are afraid of is letting go of our bodies, of life as we know it. I am 12 and do not quite know my own theory on death, but I believe death is a great mystery and I like to study the different answers and everything. My question is - Is death real and should we be afraid?

It's wonderful to hear that at the age of 12 you've already read a lot, and I'm impressed by your submission. Many people twice your age wouldn't be able to submit something so thoughtful. I would recommend that you take a look at the essays in John Martin Fischer's edited volume on the metaphysics of death . I found it helpful when I read it many years ago; it contains both tough-minded philosophy and also bits of comic relief. You may find it a challenging read, but I don't think it's beyond you. Nowadays there may be more up-to-date collections on the topic, but Fischer's volume is an excellent place to start.

Can we unknow what we already know?

I'd say yes . One way would be if (for whatever reason) you ceased to believe some proposition P that you formerly knew to be true. If belief is a precondition for knowledge, then you'd no longer know that P. Another way might be, while retaining your belief of P, to come to believe (or indeed even know) some proposition Q your belief of which undermines your justification for believing P and thereby deprives you of the knowledge of P that you formerly had. See Carl Ginet's article "Knowing Less By Knowing More" (linked here ).