[lit-ideas] Re: Philosophical points

Eric Dean writes
First, I completely agree that "there exists" is a problematic expression. I think, though, that Quine's usage is both decipherable and coherent, though I do have my doubts about the entire program within which that usage makes sense. 

What dire offense from logic textbooks springs
What mighty contests rise from trivial things!
I think that the principle of charity should be applied to the 'existential quantifier,' which can without loss of meaning be read simply as 'there is…' 'There's a spot on your tie.' would be formally written using the existential quantifier but this doesn't mean that what the logician means is anything more than what the ordinary person means by 'there is.' Logic is a formalization of stuff from elsewhere, mainly ordinary language. Logical formalization is rarely more perspicuous than that of which it is a formalization of: 'The cat is on the mat,' is fairly easy, but 'Tom has six goats, two of which are for sale,' is more difficult, and in formal notation less readily intelligible to the common reader.
The usage derives from the notion that time can be treated, for purposes of science, as a fourth spatial dimension. In that sense, one can say "there exists" a time t such that..." in the same way one can say "there exists a point p such that...". In this usage one can say "there is a time t such that t is greater than 5:00PM EST on March 21 2008 and the sun sets in Washington DC at t" and mean something like "the sun will set later this afternoon", tortured as such a way of saying it might be. In the case of the restatement of "all men are mortal", this all cashes out as simply meaning that a mortal man will die some time, surely not a problematic notion on any construction.
This is interesting but I wonder if Quine meant any more than 'every man will someday die,' which, as an empirical generalization I'd be inclined to agree with. What counts as dying is often stipulative and different criteria for death ('x is dead') have been advanced over the years. The troublesome formalization cannot itself mean anything that can't be said in ordinary language; it requires no occult interpretation, as far as I can tell. Like Augustine, when I think about time, I understand it, but when I try to explain it, I don't. In any event, it isn't the logician's job to tell us when people are dead (or happy or male or female). The logician's arrogance is perhaps an illusion: she's saying, in effect, whatever you've agreed counts as being dead (happy, female, a True Trotskyite), we'll use that.
While such circumlocutions may usefully (?) make explicit the logical underpinnings of the mathematics which in turn underpin physics, I certainly agree that they're of dubious value in the case of "all men are mortal".
I think it was agree some time back that logicism (the attempt to ground mathematics in logic, or in the logic of set theory), was a failure. 

Robert Paul
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