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Re: Formal Semantics for The Logic of Presuppositions
Posted:
Sep 27, 2011 8:02 PM


On Sep 27, 12:29 pm, "Jesse F. Hughes" <je...@phiwumbda.org> wrote: > Newberry <newberr...@gmail.com> writes: > > Let's see what we did with > > > ~(Ex)(Ey)(x + y < 6 & y = 8) > > > We identified the element that satisfies (y = 8) and assigned it to y, > > and we got > > > ~(Ex)(x + 8 < 6) > > > How about > > > ~(Ex)(Ey)[~N(x*y) & N(y)] > > > It is different in the sense that there are infinitely many horizontal > > stripes. But we listed all of them > > > (Ay)(2 * y) > > You do realize that the above is literally meaningless, right? > I mean, you spend a considerable amount of time pondering over > meaninglessness, so surely you can recognize that (Ay)(2 * y) has no > evident meaning. > > > and observed that if any of them is multiplied by any n, the result > > satisfies N(): > > > (Ax)(Ay)N(x * (2 * y)) > > > This is the general method. And why cannot we do the same thing with > > all the examples you have listed? > > Let me know if you can do it with > > (Ax)(Ay)( x + y > x > y > 0 ). > > Note: I intend this as a formula interpreted in Z, not in N, so NOT(y > > 0) is *not* equivalent to y = 0. For now, let's take the language of > the theory to consist of a single constant, 0, a single function symbol > + and a single relation >.
Let's stick with N for now. It is better to do it one step at a time.
> > So far, your judgment that such formulas are equivalent to nonredundant > versions consist of seeing that two of them are thus equivalent and > guessing that they all are. Why didn't you try to do the same thing > with all the examples I have listed, rather than ask why we cannot? > > Give it a shot. > >  > "People just love to talk. > People just love to talk. > If you don't know somethin' then don't say nothin'. > People just love to talk."  Delbert McClinton Hide quoted text  > >  Show quoted text 



