Re: Conjunctions, conjunctive adverbs, subordinators

* Patrick Littell said on 2006-03-17 01:30:07 +0100
> On 3/16/06, Patrick Littell <puchitao@...> wrote:
>
> > You can make do with just IF and NOT; Lukasiewicz's axiomatization of
> > sentential logic has these as the primitives, iirc.
> >
> > A OR B = IF NOT A THEN B
> > A AND B = NOT ( IF A THEN NOT B )
> >
>
> Looked it up: although Lukasiewicz's axioms only make use of IF and
> NOT, it looks like he actually chose IF and AND as the primitives, and
> then defined IF as NOT ( A AND NOT B).  I found his axioms, too:
>
> 1.  ( P => Q ) => ( ( Q => R ) => ( P => R ) )
> 2.  P => ( ~ P => Q )
> 3.  ( ~ P => P ) => P
It seems conditional particles was a bad place to start, too easy to mix
up maths/logic with language. The discussion so far might of course help
creators of loglangs and engelangs, but I create neither. I'll try to
collapse one of the many other sets of meaning-similar junctions in a
later mail.


t.