Re: TMRM: isa/sub - irreflexive relation vs. reflexive relation

On Wed, Oct 05, 2011 at 10:23:11AM +0100, Simon Grant wrote:
> On 5 October 2011 10:05, Lars Heuer <[email protected]> wrote:
> 
> > [...]
> >
> > I understand why the "sub" relation is reflexive (implicitly since
> > every proxy is a subclass of itself by definition), but I wonder why
> > stating "x isa x" is explicitly forbidden.

It is not forbidden. You can still state it. But it is not implicitly
given by TMRM semantics. So if you assert

   lheuer isa person

there is no implicit knowledge that

   lheuer isa lheuer

   person isa person

> Maybe it helps avoid Russell's Paradox? [1] or something similar? Just a
> guess...

Well, the world would not implode with a different semantics, but the
taxonometric reasoning might bring up eyebrow-raising results.

\rho