Several years ago I prepared a point-by-point response to this postscript as a working paper for the NYU Colloquium in Legal, Moral and Political Philosophy. I have not yet published that paper, but I understand that copies of it are in circulation. I do not intend to recapitulate the arguments of that working paper, but instead to concentrate on one aspect of Hart’s Postscript, which is his defence of Archimedean jurisprudence. I shall have something to say about his own legal philosophy, which was a form of legal positivism. But I shall mainly be concerned about the method that he said generated his legal positivism.