Philosophers frequently treat certainty as some sort of absolute, while ordinary men typically do not. According to the Theory of Important Criteria, on which the present paper is based, this difference is not to be explained in terms of ambiguity or vagueness in the word?certain?, but rather in terms of disagreement between ordinary men and philosophers as to the importance of one of the criteria of the ordinary sense of?certain?. I argue that there is reason to think that certainty is (...) some sort of absolute, and thus that no empirical statement is certain. And in any case, the problem of empirical certainty is not a pseudo?problem, as metaphilosophers like Wittgenstein and Wisdom have thought. (shrink)