[CL] Why Don't We Need Free Variables?

[Randall R Schulz]

Pat,

On Monday 01 August 2005 22:56, Pat Hayes wrote:
> >...
> >
> >In any event, there are valid circumstances in which an open formula
> > is what's needed and intended.
>
> I do not know of any that cannot be described as conventions for
> using names or quantifiers, both of which are provided in CL.

This is an odd suggestion, given that you rejected using lexical 
patterns to distinguish variables from other named entities.

And it makes no sense to use a quantifier to introduce a free variable, 
does it?


> >...
>
> I think it would be a serious logical mistake to allow [open formulas]
> in, if they really are a third category of binding. But let me
> suggest: if you feel that open formulas are meaningful and useful, and
> represent a kind of logical content, that you provide an extension to
> the CL model theory to explain what their truth conditions are.

Why must formulas that do not in themselves express a truth value be 
excluded?


> Pat


Randy