Self-Identification and Some Versions of the Dream-Argument

Abstract

Wittgenstein's general anti-sceptical argument included in On Certainty can be called
an argument from semantic certainty: A sceptic must acknowledge that he understands
sentences, which he undermines. But when the sceptic claims that he has a reason to
doubt all sentences and, at the same time, that he understands the sentences he
doubts, he contradicts himself, because one cannot doubt all sentences and understand
any of them. Since some sentences are meaning-bearers of words, a total doubt implies
complete lack of understanding of their meaning. This argument is expressed in a
pragmatic stylization: since some assertions are meaning-bearers, a total doubt would
amount to complete lack of understanding.