Hume on is and ought

Abstract

Was Hume here1 claiming or implying that propositions about what men ought to do are radically different from purely factual propositions, and that they cannot ever be entailed by any purely factual propositions? No, despite Mr Hare, Professor Nowell-Smith, Professor Ayer, Miss Murdoch, Professor Flew, Mr Basson, and the Observer’s Brief Guide to philosophy.