Colours are physical properties of external objects. One such colour
is Pure Green: the shade of green that looks not at all yellowish or
blueish. However, if people are asked to identify the shade of green
that looks not at all yellowish or blueish, they come up with
(slighly) different shades: what looks pure green to me looks slighly
blueish to you; what looks pure green to you looks slightly yellowish
to me. What shall we make of this?
We could claim that one of the groups is simply right about Pure
Green and the other wrong, even though there is no way to find out which is which. That is incredible.
I've just noticed that I don't understand those who do not base semantics on use, so I'm asking you for hints or pointers.
Here, very roughly, is the position I don't understand:
Speakers of a language have tacit knowledge of its syntax and semantics. Take Karl. As a competent speaker of German, he tacitly knows that, say, "Berlin" denotes Berlin, "pleite" denotes (or expresses) the property of being broke, and "x ist y" is true iff the thing denoted by x has the property denoted by y. Thus he knows that "Berlin ist pleite" is true iff (or expresses the proposition that) Berlin is broke. That explains why he comes to believe that Berlin is broke upon hearing trustworthy people utter "Berlin ist pleite", and that's why he himself utters "Berlin ist pleite" to tell people that Berlin is broke. The object of semantics is this tacit knowledge of speakers. It has nothing intrinsically to do with use, conventions and the like.
I hope this sounds familiar. I think it's a pretty common position, so I'm a little worried that I don't understand it.
Since 2006, state employees here in North Rhine-Westfalia receive their monthly salary at the end of each month. This looks like an interesting way for the state to get a lot of money without taking it away from anyone.
Suppose for simplicity that we get our salaries exactly one month later than before. Then from the point of view of the state, it's like they just didn't pay anyone for a month: we got our payment in December, January was skipped and we got the next payment in February. But from our point of view, it's not at all like we didn't get paid for a month. Ater, say, my one-year employment, I will have earned the same amount I would have earned without the change. Likewise for everyone else, except for those who are employed infinitely long. OK, we have small loss in convenience and interest revenues, but that loss is worth far less than a monthly salary.
So in effect, despite the fact that North Rhine-Westfalia didn't pay any salaries for one month, all employees of North Rhine-Westfalia get payed for each month they work. Clever.
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Kaplan, "Demonstratives", p.500:
[I]f I say, today,
I was insulted yesterday
and you utter the same words tomorrow, what is said is different. If
what we say differs in truth-value, that is enough to show that we say
different things.
This criterion is frequently echoed. Here, for instance, is Lycan, Philosophy of Language, p.93:
...words on Twin Earth and the rest diverge in meaning from their counterparts on Earth. Of an Earth utterance and its Twin, one may be true and the other false; what more could be required for difference of meaning?
But the criterion strikes me as very implausible. Consider a possible world
that differs from ours only by containing an extra isolated electron in some remote part of the universe, far outside our galaxy. When I say
"the number of electrons is even", my utterance differs in truth value
from the corresponding utterance of my twin at this world. Does it follow that we mean different things by "number" or "electron"
or "even" (or "is")? No. The obvious explanation is rather that what both
of us mean happens to be true in one world and false in the other.
I think one should not define "context of utterance" so that a context of utterance for an expression must always contain an utterance of the expression (or "truth in a context of utterance" so that a sentence can only be true in a context where it is uttered).
This obviously depends on how or where the term is meant to be used. The use I have mostly in mind is in the semantics/pragmatics of context-dependence, or indexicality.
Competent speakers of English know how to determine the semantic value(s) of a sentence uttered in a given context. Take truth value: we know that
A quick Google search didn't come up with anything, so here are a couple of questions about the definability of certain unary quantifiers.
Just as all truth-functional operators are definable in terms of the Sheffer stroke, all numerical quantifiers are definable in terms of
together with truth-functional operators and identity. By a numerical quantifier I mean a quantifier like "at least one", "at least two", "exactly 17", etc.: a quantifier Q such that the truth value of QxA(x) is determined by the finite cardinality of the objects satisfying A(x).
I'll be in Trento, Italy, next weekend. If anyone know a cheap place there to sleep and shower, please let me know.
Update 2006-05-02: I'm back. I've lived at Youth Hostel Giovane Europa, which is close to the station, 13,50 Euros per night and quite ok (as long as you don't mind an old man who only speaks Italian sleeping in your bed when arriving at night.)
I just realized that I don't know what my telephone number is. I used
to think it is 44717384. But 44717384 is a number, and the same as
252452510 in octal, or 2aa5548 in hexadecimal. Yet it sounds wrong to
say that my telephone number is 252452510 in octal, or that my
telephone number begins with 4 only in decimal notation. What's more,
telephone numbers are never pronounced "forty-four million, seven
hundred and seventeen thousand three hundred eighty-four". (I know an
old woman in a rural part of Germany whose number used to be 543; she, too,
always said "five four three".)
When sometime between 1986 and 2001, Lewis accepted (a certain version of) standard quantum physics, did he thereby accept that Humean Supervenience is false? I'm not sure. My knowledge of quantum physics ("knowledge" in the sense of "probably false, unjustified guesses" rather than "true, justified beliefs") doesn't suffice to see through this with any confidence. Anyway, here's some thoughts.
Humean Supervenience is the hypothesis that in worlds like ours, all
truths supervene on the spatiotemporal distribution of fundamental
properties at spacetime points. This appears to contradict what quantum physics says about entangled states: if two electrons are suitably entangled, their combined state is a superposition of X-spin(electron 1)=up & X-spin(electron 2)=down and X-spin(electron 1)=down & X-spin(electron 2)=up (
, or so), which is not determined by any local qualities of the individual electrons: there are no spin states A and B such that whenever some electron is in A and another one in B, then their mereological fusion is in this entangled state. So Humean Supervenience is false.