Since we can never know anything for sure, it is simply not worth searching for certainty; but it is well worth searching for truth; and we do this chiefly by searching for mistakes, so that we have to correct them.

Sir Karl Popper (1902-1994) Austrian-British philosopher

“Knowledge and the Shaping of Reality,” lecture, Alpbach (Aug 1982)
    (Source)

Reprinted in In Search of a Better World, ch. 1 (1994).