Why can’t we know the truth about the empirical world a priori? This question is equivalent to asking why we should be fallibilists in the first place, or why open-mindedness is the essence of science. We should be fallibilists only because, and to the extent that, we are not omniscient. We should be open-minded only because, and to the extent that, the world is complicated (to us).
— Jeffrey Friedman, “Popper, Weber, and Hayek: The Epistemology and Politics of Ignorance,” Critical Review 17, 1–2 (2005), p. 9.