The technologists of power are today’s true rationalists. That superior intelligence is found among the practitioners of populism is a fact of our time. When liberals talk about reason they mean a mishmash of ideas they picked up at university. Scraps of Rawls, Dworkin and Thomas Piketty, together with a smattering of modish conspiracy theories, form the folk wisdom of the thinking classes. Rationality means deferring to this ragbag of ephemera and ignoring enduring truths about the deciding forces in politics.