Abstract:

The old issue of the theory issue of knowledge, "I believe p" has turned a linguistic one in Wittgenstein's philosophy. It consists of three relevant issues: "I believe p", "I believe~p" and "I know p". The conflict of "I believe p" with the basic propositions of Wittgenstein's logic philosophy is one of the theory sources for Wittgenstein's linguistic turn, and the subjective certainty existing in "I believe p" provides the possibility for the humanities.

Key words: Wittgenstein, "I believe p", "I believe~p", "I know p"