Yet another paper on counterpart-theoretic semantics: Generalising Kripke Semantics for Quantified Modal Logics. This one is a bit more technical than the others. I use a broadly counterpart-theoretic model theory to construct completeness proofs for very basic quantified modal logics, such as the combination of positive free logic and K. I also play around with adding an object-language substitution operator. There are some unfinished sections at the end, but since I haven't been working on this since January, I thought I might as well upload the current version. All the proofs are spelled out in detail, which makes the whole thing ridiculously long.
I'm not much of a logician, so I'd be very interested to hear if this looks like it is worth pursuing any further.
I've thought a bit about counterpart-theoretic semantics last year, both for natural language and for quantified modal logic. Here's a paper in which I present my preferred version of this framework as applied to natural language: Counterpart Theory and the Paradox of Occasional Identity. Apart from the semantics itself, my main claim is that the advantages of counterpart semantics do not require the metaphysics of "counterpart theory".
I've just replaced the Online Papers in Philosophy Feed by a newer version. Let me know if you run into any problems with that. (You may also consider switching to a feed from PhilPapers.)
To some extent, one can account for semantic phenomena without
assigning meanings to words or sentences or thoughts. For instance, we
might say that beliefs and other attitudes are relations to
sentences, i.e. to strings of symbols. Roughly, to believe a
sentence S is to be disposed to utter (or assent to) S (or some
translation of S) under certain conditions. When people talk to each
other, such dispositions may be transferred: after hearing
me utter the sounds "it is raining", you acquire the disposition to
utter those sounds yourself. Apart from communication, we can also
account for things like synonymy and analyticity. Roughly, two sentences
are synonymous if necessarily, anyone who stands in the belief
relation to one of them also stands in the belief relation to the
other. There is no compositional semantics in this picture, because
there is no semantics at all. But there might be recursive rules for
translating from one language to another.
A lot has been written in the last 10 years or so on updating
self-locating beliefs, mostly in the context of the Sleeping Beauty
problem. One thing almost all of these papers have in common is that
they quote Lewis's remark in "Attitudes de dicto and de se" (1979,
p.534), where he says:
Professor Procrastinate has to make an important phone call. The
call is long overdue because Procrastinate has been playing Farmville
all week. The problem is that Procrastinate values current pleasure
higher than future pleasure. So when he applies his decision theory,
he finds that it is better to play some more Farmville now and make
the phone call later instead of making the call now: it doesn't matter much
whether the call is delayed by a few more hours, and this way the
immediate future will be much more pleasant.
There has been some discussion recently about whether propositions
are true or false absolutely, or only relative to a possible world, or
relative to a world and a time. What hasn't been considered, to my
knowledge, is whether propositions are true or false only relative to
a branch of the wave function of the universe.
In metaphysics, "Humeans" are people who believe that truths
about laws of nature, counterfactuals, dispositions and the like
(truths about what must or would be the case) are in
some sense reducible to non-modal truths (about what is the
This paper (recently
featured on the
physics arXiv blog) argues that if the universe never comes to an
end, then the universe will probably come to an end within the next 5 billion
years. The reasoning, as far as I can tell, goes roughly like
OK. We're back in Canberra. I've also finished the completeness proof
that I've been working on for the last few months. More on that soon. In the
meantime, here are some pictures from this year's bike
trip through the Alps.