Oracle: No man is wiser than Socrates. (IP3 12b)

Socrates tries to prove the oracle wrong.

He searches for someone wiser than he. (Politicians, poets, artisans) He finds others aren't as wise as they appear.

He concludes: He has a wisdom that they don't have:

Socrates: "I am better off than he is--for he knows nothing, and thinks that he knows; I neither know nor think that I know. In this latter particular, then, I seem to have slightly the advantage of him." (IP3 12b)

Neither he nor they know anything (important), but they think they do and Socrates knows that he doesn't know.