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Topic: Formal Semantics for The Logic of Presuppositions
Replies: 3   Last Post: Sep 27, 2011 8:14 PM

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Newberry

Posts: 915
Registered: 6/4/07
Re: Formal Semantics for The Logic of Presuppositions
Posted: Sep 27, 2011 8:02 PM
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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 non-redundant
> 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 -





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