"[T]he paradox lurking at the heart of Karl Popper's career... Everyone says this opponent of dogmatism is almost pathologically dogmatic. ...Popper scoffs at scientists’ hope that they can achieve a final theory of nature. "...I think we have gone very far, but we are much further away." He... returns with his book Conjectures and Refutations... [and] reads his own words with reverence: "In our infinite ignorance we are all equal." ...Can a skeptic avoid self-contradiction... the Popper paradox? And if he doesn’t, if he preaches but fails to practice intellectual doubt and humility, does that negate his work? Not at all. Such paradoxes corroborate the skeptic’s point... the quest for truth is endless, twisty and riddled with pitfalls, into which even sharp-eyed seekers tumble. In our infinite ignorance we are all equal."