Re: Yet another inane amateur Godel question

Aatu Koskensilta wrote:

it is a fundamental element of the
classical predicativist conception that there simply is no determinate
totality of all sets of naturals.

Is the 'classical' predicativist position that it's definitively -true- that there -is- no such a thing, or only that it's not acceptable to use it as an assumption in proofs?

If the former: is this seen as a priori clear, on philosophical grounds, or as something that requires proof? What proof do they have for it?

(Underlying question, tongue-in-cheek: could the diagonal argument be interpreted to be such a proof?)

--
Cheers,
Herman Jurjus
.

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