Re: Columns without names

paul c wrote:
> vc wrote:
> > JOG wrote:
> >> While I have your attention perhaps you might also clarify a
> >> distinction that I previously had:
> >>
> >> I was under the impression that - given that the extension of a
> >> predicate is the set of true propositions that can be formed by
> >> substituting a term for each of its free variables
> >
> > In the mathematical context, a predicate extension is a collection of
> > things in some universe for which the predicate holds. In other words,
> > a predicate can be interpreted as a mathematical relation in some
> > domain of interpretation, or one can say that a predicate defines a
> > relation in some domain. The '<' predicate in the {1,2,3} domain
> > defines the {(1,2), (1,3), (2,3)} relation which is the predicate
> > extension.
> >
> > - a predicate
> >> /always/ has an extension.
> >
> > It depend on your favorite set theory. In some, R = {x | not( x in x)}
> > does not exist, in others it does.
> > ...

>

NBG.
>
> thanks,
> p
Received on Wed Sep 20 2006 - 18:17:15 CDT