 Though Locke’s liberalism has been tremendously influential, his political theory is founded on doctrines of natural law and religion that are not nearly as evident as Locke assumes. Locke’s reliance on the natural law tradition is typical of Enlightenment political and moral theory. According to the natural law tradition, as the Enlightenment makes use of it, we can know through the use of our unaided reason that we all – all human beings, universally – stand in particular moral relations to each other. The claim that we can apprehend through our unaided reason a universal moral order exactly because moral qualities and relations (in particular human freedom and equality) belong to the nature of things, is attractive in the Enlightenment for obvious reasons. However, as noted above, the scientific apprehension of nature in the period does not support, and in fact opposes, the claim that the alleged moral qualities and relations (or, indeed, that any moral qualities and relations) are natural. According to a common Enlightenment assumption, as humankind clarifies the laws of nature through the advance of natural science and philosophy, the true moral and political order will be revealed with it. This view is expressed explicitly by the philosophe Marquis de Condorcet, in his Sketch for a Historical Picture of the Progress of the Human Mind (published posthumously in 1795 and which, perhaps better than any other work, lays out the paradigmatically Enlightenment view of history of the human race as a continual progress to perfection). But, in fact, advance in knowledge of the laws of nature in the science of the period does not help with discernment of a natural political or moral order. This asserted relationship between natural scientific knowledge and the political and moral order is under great stress already in the Enlightenment. With respect to Lockean liberalism, though his assertion of the moral and political claims (natural freedom, equality, et cetera) continues to have considerable force for us, the grounding of these claims in a religious cosmology does not. The question of how to ground our claims to natural freedom and equality is one of the main philosophical legacies of the Enlightenment.