In a piece for the Library of Law and Liberty, Dalrymple points out the obvious flaw in the arguments of psychologist Daniel Kahneman, who says that humans are fundamentally irrational:
Just as the role of rationality can easily be overestimated in human life, so can that of irrationality. Turned into an epistemological principle, the idea of irrationality falls foul of a kind of Cretan paradox. If all human beliefs are irrational, then there can be no rational grounds – at least for humans – for believing that they are.
Read it here