Here comes the solution to this year's Christmas puzzle:
First, is the story in the museum true or false? The crucial question is whether the last sentence in it is true. It goes:
*) If the story is true, the oracle finds out that it is.
Under what conditions is (*) false? It is false iff i) the story in the museum is true, but ii) the oracle doesn't find out that it is. On the other hand, since (*) is part of that very story, if (*) is false, the story is also false. So if (*) is false, the story is both true and false. So (*) can't be false.
The Museum of the Myth is not very comprehensive. In fact, it only contains a single story:
The Museum of the Myth is not very comprehensive. In fact, it only contains a single story. The story is not particularly exciting. Moreover, some people wonder whether it is actually false. If not, it would of course be incorrectly classified as a myth. So one day, the oracle is asked about the story. Luckily, the oracle is quite reliable: if the story is true, it undoubtedly finds out that it is.
The story is not particularly exciting. Moreover, some people wonder whether it is actually false. If not, it would of course be incorrectly classified as a myth. So one day, the oracle is asked about the story. Does it find out whether it is true?
If haecceitism is true, materialism is false. For if haecceitism is true, there is a world w just like ours except that you and I have traded places. By that I don't mean that in w someone with my origin or my DNA or my soul leads a life quite like yours. No, haecceitism holds that it is possible for us to trade places completely, so that in w not only my life is just like your actual life, but also my origin, DNA and soul are just like your actual origin, DNA and soul. w and our world do not differ in any qualitative respect at all. They differ only in facts that essentially involve you or me, such as the fact that in w it's you who is writing this posting. Whatever 'physical' means, it is clear that the physical facts are not of this kind. That's why materialism is false if haecceitism is true: Materialism demands that there is no difference at all between our world and any minimal physical duplicate of it.
Geoff at Too Much Text points out that the implausible hyper-essentialism implied by Kripke's account of rigidity can be avoided by adopting radical anti-essentialism, the view that there are no non-trivial (qualitative) essential properties at all. On this view, even though there is a precise boundary between a thing's essential and non-essential properties, the boundary is not very mysterious because it classifies virtually all properties as non-essential.
I want to write something about rigidity in the philosophy of mind. But first I have to say more about rigidity. (Apologies in advance: this is all going to be rather basic. But I'll need it, and I found that many people disagree with it.)
Recently I argued that the assumption that ordinary proper names are rigid designators leads to an implausibly excessive form of essentialism. But I don't want to deny the useful distinction between rigid and non-rigid designators. That is, in a sense I do believe in rigid designators. But they are not quite what rigid designators are usually supposed to be.
In my last post,
I said that I do not believe that every extended thing must have parts. Sam disgrees, arguing that whenever something is extended over length h, we can restrict our attention to a part of it with length h/n for any n < h.
I do agree that all ordinary extended things have parts. And I do agree that extended things without parts are really very strange. I'm just not sure that they are impossible.
There are lots of distinctions between perdurantism and endurantism (or better, between different perdurantisms and endurantisms). Here I want to talk about the following perdurantist claim:
1) Some things (that are not events) have temporal parts.
This does not imply that ordinary things like buildings and persons have temporal parts. And even if one believes the latter, it is still perfectly coherent to reject any account of intrinsic change in terms of temporal parts, or reject an account of personal identity in terms of (properties of) temporal parts, or reject an account of persistence in terms of temporal parts, or reject whatever else temporal parts are used to account for. It is also okay to accept only some of these accounts and reject others. (I for example am a perdurantist who rejects the account of persistence in terms of temporal parts: not only can I say what it is to persist through time without mentioning temporal parts, I even believe that it is possible for a thing to exist through time without having temporal parts.) That's how we get so many perdurantisms and endurantisms. (I think it would be very helpful if people discussing this matter exactly said what they say on each of these issues rather than vaguely asserting that, e.g., things are 'wholly present at different times'.)
What do types, sets, universals, increases, theorems, species and governments have in common that distinguishes them from sticks, stones, mountains, molecules and cities? It's not that only the latter are causally efficacious: on many accounts (e.g. those of Lewis and Kim), events -- the paradigm examples of causal efficacy -- are sets; and why shouldn't one say that if a thing's being charged produces an effect, Charge (the universal) is just as much responsible for this as the thing itself? It's also not that only the latter are located in space or time: impure sets, species, Aristotelian universals and governments arguably are spatiotemporally located as well. And by the Helen Cartwright Theorem Theorem, theorems are sometimes written on blackboards. Indeed, I'm not sure whether anything at all clearly fails to be located in time, unless we require that something located in time must undergo intrinsic change or have a beginning or an end, which sounds ad hoc. Without such restrictions, I can't see a reason to deny that e.g. numbers exist at every time. (Oddly, I'm less inclined to say that numbers exist everywhere. But I might get used to it.)
Entering the philosophy library of Humboldt University got rather unpleasant two weeks ago when a couple of students decided to occupy the building as a kind of protest against planned cuts and tuition fees and capitalism and whatever. I partly support their aims (though I think cuts in the philosophy department would be quite appropriate, given its quality, and I certainly don't want any more 'democratization' of the university), but I don't see how occupying the buildings and keeping me away from doing philosophy is a good way to achieve these aims. Anyway, I'm now in Bielefeld where there are no strikes. I'll probably return to Berlin on Saturday.
y(Iy
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