[FOM] Paradoxicality and normal-form proofs

[schiphol@altern.org]

Dr. Tennant writes

>I claim that paradoxicality consists in THERE NOT BEING 
> any normal-form
>proof, or normal-form disproof, of the statement in
>question 

Doesn't this amount to forbid all self-referential sentences? I don't see the way to give a normal-form proof for:

"This sentence is true"

which, intuitively, I would just classify as true with no further complication.

Is there any benefit of your proposal over and above Russell's theory of types or Tarski's language-level theory?

Best,
Manolo