There are two ways of denying that the future is real. One is to accept statements about the future as true but to interpret them in a way that does not require the existence of their subject matter. This is a kind of fictionalism or ersatzism about the future. (It's interesting by the way that abstract ersatz futures clearly don't count as futures, whereas it is controversial whether abstract ersatz worlds should count as real possible worlds.) The other way of denying the reality of the future is to reject the assumption that statements about the future are true. Then no fictionalist or ersatzist story needs to be told to account for their truth.
I agree that it sounds fairly plausible to say that phenomenal states have a kind of representational content built into them. But I don't find that plausible anymore if it's combined with the assumption that being of phenomenal type Q is an intrinsic and essential property of phenomenal states. Here's an intuition pump.
Consider a world just like ours except that flying-pigs qualia have traded places with crooked-image qualia. That is, in this world, people have the kind of phenomenal experience we have when we look at flying pigs when they look at crooked images, and vice versa. But our duplicates at this world are not halluzinating flying pigs when looking at crooked images. No, they are not at all mislead by their experiences. For instance, they are not at all inclined to say that there are flying pigs, or that they are seeing flying pigs in these cases. Nor do they draw any of the inferences we would draw if we had the impression of seeing flying pigs. Instead, they typically infer that they are looking at a crooked image. And they would judge their experience to be veridical just in case there really is an image hanging crooked before them.
As promised here are some remarks on the content of phenomenal states. Or rather, on Horgan and Tienson's remarks on the content of phenomenal states in their paper "The Intentionality of Phenomenology and the Phenomenology of Intentionality". Dave Chalmers pointed me at that last week. I should say that this post is not meant to be a response to Dave's comment. I can't respond to it yet because I haven't understood it yet. I'll have to read the other papers he mentions.
Suppose we want to know whether some thing A has the property of representing B. The first thing to do is to ask what exactly is meant by "representing" in this context. That is, we must inquire into the general conditions under which it would be true that some x represents some y. Then, in a second step, we have to find out whether these conditions are satisfied by A and B.
When I say that semantic properties aren't primitive I mean that there must be an informative answer to the first question for semantic terms. That is, it must be possible to spell out general conditions under which something represents or means or denotes y. And the answer must be specifiable in non-semantic vocabulary. We can do better than saying that x represents y iff it represents y. The answer needn't be simple, nor immediately obvious. As usual, the best approach might be to use thought experiments: if such-and-such were the case, would x represent y? If yes, "such-and-such" can be added as a disjunct to the conditions under which x represents y.
Most of the 5.3 million results Google returns for 'David Lewis' aren't about David Lewis the philosopher. The 53000 results for '"david lewis" OR "david * lewis" ~philosophy' look more promising. But even they contain lots of completely irrelevant stuff (like this one), and many of the not completely irrelevant results are uninteresting pages at bookstores selling one of Lewis' books.
Brian still believes that impossibilities are true in some fictions. I still disagree. But I wonder if the disagreement is substantial. Of course I agree that in some fictions one can find impossible statements. The question is whether these statements are true in the fiction. Not everything that is explicitly said in a fiction is true in the fiction. I'm now inclined to believe that our conception of truth in fiction may be ambiguous: on the standard conception, impossible fictions are ruled out; but on a different conception, they are tolerated. Let's call the former conception 'intensional' and the latter 'hyperintensional'.
Non-reductive (a posteriori, type-B) materialists say that even though phenomenal terms denote physical states or properties, the phenomenal way things are is not a priori entailed by the physical way things are. This means that no amount of physical information can tell us what our phenomenal terms denote. That is, non-reductive materialism implies that the projects of naturalising linguistic and intentional content are doomed. I would say that contraposititvely, since there are good reasons to believe in the project of naturalising linguistic and intentional content, non-reductive materialism is doomed.
If Tina is a time traveler who is free to change the past, it must be true that
1) if Tina had chosen 1928, a time traveler would have appeared in 1928.
Moreover, this must be true on a "non-back-tracking" interpretation. A back-tracking interpretation is one on which we consider how past events would have had to be in order to cause some later event. Let's see how (1) fares on Lewis' conditions for non-back-tracking counterfactuals (in "Counterfactual Dependence and Time's Arrow").
Brian Weatherson:
We know that positive conceivability is a good inductive guide to possibility. And we know negative conceivability is a good inductive guide to possibility.
What kind of induction is this? What we do know is that sometimes what seems conceivable on first sight later turns out to be incoherent (and thus inconceivable in the technical sense introduced by Dave Chalmers and deployed by Brian). We also know that this doesn't happen very often, and that it happens mainly when we consider rather complicated stories or hypotheses. So we have good inductive reason to assume that there is no hidden contradiction in, say, the hypothesis that there could be an apple in a basket. But this only supports the claim that prima facie conceivability is a good inductive guide to ideal conceivability.
The standard solution to worries about time travelers' freedom to 'change the past' rests on a distinction between legitimate and illegimitae facts in such considerations. (See e.g. this great paper by Ted Sider.) Assume for simplicity that x is free to do y iff he really would do y should he decide to do y. Now consider Tina the time traveler. Is she free to kill her earlier self? I.e. is it true that