It would seem to me that I don't have to have ever witnessed a particular phenomena to be able to recognize evidence of it. For example, if I were to see a set of footprints in the sand, and on every left footstep there's a small hole, I might explain this finding by hypothesizing a person walking across the beach with a nail stuck in their shoe. Of course I understand that it could be explained in an other way, but if that was actually what had happened and I'd never before seen a person walking with a nail in their shoe then I'd have recognized evidence of something that I'd never seen before. But I have experienced footprints and nails before so perhaps I'm mistaken. My question then is, Is it possible to recognize evidence of something I've absolutely no experience whatsoever of? And what are the implications to the idea of sense data being evidence of the external world (if our only evidence of the external world is our sense data, how can we hypothesize an external world to explain such data when...

Let's start with the more general question: is it possible to recognize evidence of something that we had no experience of before? The answer seems pretty clearly to be yes, since we've frequently found good reasons to believe in various such things. We have evidence for black holes, for example. We have evidence of the existence of various exotic particles. Although the details are complicated, the way this works can be explained in this sort of way: We're interested in whether there are Xs. We ask: what would we expect to see if there were? What evidence E would Xs produce? And how likely is it that we'd find E if there were no Xs? Assuming that the "prior probability" of Xs isn't too low (assuming, for example, that Xs would have a sensible place in our larger scheme of things), assuming that the probability of E given X is appreciably greater than the probability of E given not-X, finding E might well give us good reason to think there are Xs. Or at least, this is a fairly common kind of story...

Can a philosopher please help us understand why it is so painful when someone you acknowledge disregards you in turn? Thanks, from South Africa.

Sorry you've been having this sort of experience. And the amount of time it took for any of us to reply may give you the same sort of feeling you were asking about. But let me at least start with a possibly lame excuse. It sounds like what you want to know may be something more in the realm of psychology: what is it about how our minds work that can make snubs, rejection and the like psychologically painful? Why don't we just shrug it off?And insofar as the question deals with how minds actually work, philosophers aren't necessarily the best experts. That said, we're in a domain where ordinary experience and insight may be able to shed some light, so let's give it a try. Part of the answer is that we sometimes do shrug such things off. If I nod to a stranger on the street and he doesn't nod back, I might experience a momentary sense of annoyance, but I'll probably have forgotten about it literally within seconds. Whether this stranger takes account of me isn't something that matters to me. But for...

How can one determine authenticity and authoritativeness? For example, how would you gauge the authenticity of the panelists' responses? Does studying philosophy give the panelists anymore authority to issues like abortion, love, or education than the "average" non-philosopher? Is there not a little ego in that notion?

I have a little ego, so I'll offer a little answer. I agree completely: it's not necessary to have studied philosophy to be able to say sane, sensible things about abortion, love, education and so on. Indeed, it would be very bad news if being able to think well about those sorts of things called for specialized training in philosophy. And in fact, no one on this panel is an authority on what people ought to think about, say, capital punishment. The questions philosophers think about are, as it's sometimes put, essentially contested. It's in the nature of the strange business we're in that no one is an authority on the answers in the way that a physicist might be an authority about the answer to some scientific question. No one should accept the conclusions folks on this panel come to just because we're philosophers, and none of us would want anyone to do that. What philosophers are often good at, however, by skill, training and inclination, is sorting through the logical and conceptual details...

When there is no clear solution to an issue, it would seem to me that assessing risks would be the most reasonable way of dealing with it. In the case of abortion we risk a mother losing the civil right to address her pregnancy within her own moral reasoning, verses a child losing its fundamental right to live. The latter risk seems more pressing and with greater consequence. Can a struggle for justice be assessed upon risk?

You've raised an interesting question. The general approach you're suggesting sounds like a version of what's called "multi-attribute utility theory." Without going into detail, multi-attribute utility theory lets us make decisions even when different sorts of values are at stake. Acting in a certain way might carry a high risk of losing money, but a high likelihood of keeping a friend. Depending on my "trade-off weights" (roughly, how much I care about money vs. friendship), and depending on the possible results and their probabilities given various choices, the tools of multi-attribute utility theory might give me a way of picking a course of action. It seems at least plausible that we could reconstruct any rational way of making decisions within this framework, and so in principle, we might be able to represent the way we think about the case you've offered. But this is really just where all the hard questions start. The first problem is that different people will weight different values...

If we consider the possibility of superior life forms and the possibility of their interference of our own human species for their own gain, and then looking back at our own treatment of animals (inferior species), are Zoos ethical?

A nice question. The thought is something this: there might be creatures out there who are as intellectually advanced when compared to us as we are when compared to, say, three-toed sloths. If it would be wrong for those creatures to exploit us in various ways, doesn't this at least raise the question of whether it's acceptable for us to put sloths in zoos? Or conversely, if our superiority to the sloths makes it okay to put them in zoos, mightn't a race of super-intelligent aliens be justified in putting us on display or "serving" us for dinner? I'm not going to offer an opinion on whether it's wrong to enzoo the sloths, though I think that the answer depends at least partly on whether they're able to thrive in that sort of setting. But there is a point that seems to me worth raising: mere comparitive superiority may not be the issue. There may be a difference between us and the sloths that puts us in a different moral category. At least some philosophers (Kant being the most notable) think that...

Is there a logical contradiction with the notion of having two or more minds? What if it is intelligible that there are two or more minds and that you're the only "self" that is existing but you got so lonely that you created an elaborate delusion (that other minds exist) so that you can escape your loneliness? (Solipsism.) Is the plurality of minds/selves a coherent concept?

I wasn't entirely sure how many issues were on the table here. Your first question seemed to be whether it's contradictory to say that one person has two minds. But as your question continued, the issue seemed to be whether it's possible in general for there to be more than one mind. There's no obvious reason to think there couldn't be many separate minds, and of course what we usually assume is that there are. Whether solipsism is coherent is something that some people have doubted, but I've never found the doubts very convincing. So the question we'll tackle is whether you or I might have more than one mind or self. Interestingly enough, there are serious reasons for saying that the answer is yes. There are two bits here. One has to do with the brain. It has two hemispheres, and in patients with severe epilepsy, sometimes the only way to relieve the symtoms is to sever the corpus callosum -- the bundle of nerves that connects the two sides. Although there is room to argue about the details,...

Is it morally right to make fun of someone I don't even know because it's funny? The person doesn't know they are being made fun of and they most likely will never find out they were being made fun of, so, their feelings aren't in jeopardy and it's entertaining for me.

Although the issues aren't exactly the same, you might want to take a look at Peter Smith's answer to question 2012 . The fact that someone doesn't know they are being mocked or deceived doesn't imply that they aren't harmed. True, if they never find out, then their feelings may not be hurt (though see what follows), but many people -- I'm one -- find the thought of a life in which they are blissfully ignorant of how badly people think of then quite a bit less desirable than one in which they know what people really think. Now of course, it's not an all or none affair. Human nature being what it is, my profession being what it is, and having a certain sense of my own quirks, I'm reasonably confident that some people make fun of me behind my back. (I would hardly be the first teacher in that position.) This doesn't bother me, since I'm non-neurotic enough not to think that most people look at me that way. In particular, I think I have a reasonable idea (no doubt not completely accurate) ...

What good is an apology? For example, the Australian government has decided to formally apologize for the historical wrongs against the Aborigines. Isn't this just an outlet for guilt, rather than actual concern for the victims?

I think there may be two rather different questions here. The first is the general one that you begin with: what good is an apology? The second is whether in a particular case -- the apology by the Australian government in your example -- the apology might be simply a sop to the conscience. I can't pretend to answer the more particular question since I know so little about the details of the case, but what of the larger issue? Apologies by themselves may not be enough; there are plenty of cases where much more than an apology is called for. But for most of us, the practice makes sense from the inside. Suppose I have said something hurtful to you that was entirely uncalled for. Then I've wronged you. At the least, I may have made you feel bad for no good reason. I may also have made you look bad in front of others. I've put the moral relationship between us out of whack. When I apologize, I acknowledge that what I did was wrong, and in doing so, I go at least some distance toward restoring the moral...

In my philosophy class I am told that when I am in deep meditation I can understand that I am something other than a composition of body and mind and that this something other is eternal consciousness. In meditation apparently I should experience a state of detachment from both my body and my mind and apparently in this state of detachment I will realsise that I am observing my body and my mind and that this observing is proof that I am something other than my body and my mind, i.e. that I am the observer of my body and my mind and this is proof that I the observer am eternal consciousness. I find this reasoning hard to accept. Surely it is just a sensation of detachment or disassociation I am feeling and cannot be reasonably be accepted as proof of life after death, etc.

Couldn't agree more. I can imagine what it would be like to feel that I was observing my body from some detached perspective. And I can certainly imagine what it would be like to have the sense that I'm aware of various things "passing through my mind" without identifying with them. But even if it somehow seemed to me that I was actually outside my mind observing it (whatever that's supposed to mean), it is a very long step from there to conclusions about what I am, or what my mind is, and how the mind or the self fits into the rest of reality. I'd add: the experiences on offer here are interesting. But anyone who simply offers the conclusions you've described as the only reasonable way to interpret them doesn't seem to me to be doing what philosophy does. There is a large boatload of objections to the conclusion being drawn, and what someone doing philosophy would do is examine the conclusion in light of those objections. It's also worth noting that the meditative traditions don't...

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