A number of things seem to have stood fast for socrates in the course of all his examinations, things that in some sense we can say he knows. what are they?

One thing that Socrates said that has stood the test of time is that "the unexamined life is not worth living". Also, his method of investigating things of asking a series of questions to reveal the contradictions in things and arrive at the truth is a dialectical method and this method has stood the test of time which basically means that when there is a process, as the process develops, it creates its opposite such as oppression leading to resistance in human society.