I suspect I may be missing what's at issue here. Analyzing concepts is part of the philosopher's stock-in-trade, and that applies no less to scientific concepts than to other sorts. Not being a social scientists, I don't have a good, detailed feel for how social scientists use the phrase "social interaction" nor for how it fits into social science theorizing. That also means that I don't have a good feel for whether there are any meaty philosophical issues here. But I can well imagine that there might be, and insofar as there are, it's hard to see why philosophers of the social sciences wouldn't just be doing their jobs by undertaking the appropriate analyses.

The issue about so-called "future contingent" propositions isn't just about whether we're in a position to know whether they're true, but whether there are any facts for them to pick out. And that issue arises from a tempting but controversial metaphysical picture: reality as it were "unfolds" in time. Reality consists at least of what's so now, and perhaps as well of what's already taken place, but on this picture there simply are no definite facts about future events. This may seem odd at first, but a couple of examples might make it seem less so. Suppose you think that people make choices that are free in the sense of being not just uncoerced but undetermined. Mary is a juror in the penalty phase of a trial. Tomorrow she will decide whether to vote that the defendant should be executed. If you think that there is nothing that fixes her decision before it's made, you might wonder what it would mean for there to be a correct answer to the question "What will she decide?" before she actually decides...

I wonder just how widely accepted this is. I suspect that most people, including panelists here, would agree that just because someone thinks they've been harmed, it doesn't mean that they actually were. In fact, it's perfectly possible that something someone takes to have harmed them actually did them good. (You might think your boss would be upset if he knew that you stood up to some obstreperous client. I know that he'd actually be pleased; he's been looking for an excuse to "fire" this client, you've provided it, and because I tell him what you did, you'll be in for a bonus at year's end.) There are a couple of cases that might seem to support the equation of thinking one has been harmed with actually being harmed, but I'm not sure they're what you had in mind. First, suppose I think I'm in pain. It's been widely held that I can't be mistaken about this. I might be mistaken about whether the pain signals some sort of organic damage, but if I think I have a headache, it's odd to say that I don...

The difficulty here is with the idea that "objective reality" is a matter of consensus. I've heard that said often enough, though virtually never by a philosopher or a scientist. I must confess that I've never really understood what makes the idea seem plausible or attractive. Whatever the details, it seems reasonable to think that the world is the way it is whatever I think of the matter. The universe existed for eons in sublime indifference to the fact that we weren't around to have opinions about it, and after we mess things up and end our species' sojourn in the world, things will once again go on without somehow having gotten vague, fuzzy or unreal due to our absence. Gaseous gab about "consensual reality" is perennially fashionable in some circles, but the fact that some people are inclined to talk this way doesn't mean that it has a lot going for it. Of course, whether what we think about the world gets things right is another question. The plausible common-sense answer is that we're...

I don't disagree with anything that my distinguished co-panelists have said, but I'm inclined to add a few rule-of-thumb suggestions for anyone for whom this isn't a merely theoretical question. You might ask yourself: when you do this, do you feel like you're cheating on your partner? Would you feel cheated on if you found out that your partner had been doing the same thing? If the answer to either question is yes, you might want to pause and think about what you're doing and why you're doing it. Answering "yes" to either question isn't conclusive; sometimes we have feelings that turn out on close scrutiny to come from nothing other than habit and prejudice. But this is an area where self-deception is particularly easy. If you think that the nature of your relationship would make it wrong to have an old-fashioned physical affair, then you might want to ask yourself how much weight you can really put on the fact that there's no skin-to-skin contact here. People sometimes use the phrase ...

I think you've done a good job of answering your own question. Your example is a pretty clear case of someone being harmed without knowing about it.

This argument is lots of fun! Thanks for offering it. Whether it works, of course, may be another matter. There are many places to try to poke holes, and others on the panel may have their needles poised over other places. But here's my pick. Your first premise says: if the world's existence is contingent, then there is a possible world where the world doesn't exist. That sounds a little odd, and the oddness suggests that we need to be careful. Most of us think at least this much: the matter that surround us didn't have to exist. When we say that the world's existence is contingent, it's plausible that we mean something like: "The matter that happens to exist need not have existed." That seems plausibly true; it's certainly not obviously false. Consider: if physics has it right, the matter of this world obeys quantum theory. But other laws of nature seem at least possible. Arguably, matter that doesn't fit quantum principles couldn't be this matter -- the matter that makes up the stuff of ...

No. That is, it wouldn't necessarily be a good thing, and it wouldn't necessarily be a bad thing. It would depend on what this borderless world was like. There's a certain sort of idyllic situation we might imagine when we think of a borderless world where people are free (at least nominally) to live and work wherever they please. But not being someone who thinks government is inherently bad, I'm struck by the fact that governments make things possible that might be difficult or impossible without systems of taxation, law and so on. Would the borderless world be run by a single central government? If so, is it reasonable to think that any such government could rule effectively given the diversity of the world? Or would the borderless world be one with minimal government or no government? And if so, is the likely result an anarchy that would make most people worse off? My own guess, for what's it's worth, is that whatever the evils of borders may be, the overall picture would be even more problematic...

Perhaps we could make a distinction. Perhaps we could all agree that ideally , we'd all steer clear of hypocrisy. The phrase "good hypocrisy" has a strange ring, suggesting that nothing would count. The phrase "tolerable hypocrisy," however, is less strange. Few of us, if any, manage to steer clear of hypocrisy altogether, and it's doubtful whether it's morally healthy to worry too much about one's moral health. (In this connection, Susan Wolf's paper "Moral Saints," from the Journal of Philosophy August 1982 makes interesting reading.) So we can agree that no one should be condemned simply for not being absolutely beyond condemnation, but we can also agree that hypocrisy isn't a good thing. After all, if I'm being a hypocrite, my sin isn't just posing as someone who acts in accord with a certain principle. Quite aside from the dishonesty in the way I represent myself, to count as a hypocrite I have to be doing things that by my own lights, I shouldn't be doing. And depending on what those...

Just to be sure I'm addressing your worry: it's often said that there are two senses of "or": an inclusive sense, where "P or Q" means "At least one of the statements 'P' and 'Q' is true, and an exclusive sense, where "P or Q" means "exactly one of the statements 'P' and 'Q' is true." Let's suppose I'm the sort of person who makes it a practice of always using "or" in the inclusive sense. Someone who knows this hears me say: "Mary is in San Francisco or in New York City." The logic of my statement doesn't rule out all by itself the possibility that Mary is in both places. What rules that possibility out are the facts of geography and of how people fit into space and time. (It's been claimed that some saints were capable of bilocation, but we'll assume that Mary is, at least in that respect, no saint.) Could someone who knew that I'm an inclusive "or" sort of guy but didn't know much about geography and the relationship between people and space correctly infer that if my statement is true, then Mary...