A central theme in F. A. Hayek’s work is the contrast between principles and expediency, and the insistence that governments follow abstract general principles rather than pursue apparently expedient social and economic policies that seek to make us better off.2 This is a radical and striking thesis, especially from an economist: governments should abjure the pursuit of social and economic policies that aim to improve welfare and, instead, adhere to moral principles. In this chapter I defend this radical claim. I (...) begin by explicating and defending Hayek’s argument against the pursuit of expediency based on his analysis of economic and social complexity. I then turn to a rather more critical examination of his evolutionary account of moral principles. (shrink)