 Hutcheson’s opposition to Hobbesian egoism is matched by his opposition to ethical rationalism, an opposition which emerges in the Illustrations upon the Moral Sense, where he demonstrates that his account of the affections and the moral sense makes sense of the moral facts whereas the doctrines of Clarke and Wollaston totally fail to do so. Hutcheson’s main thesis against ethical rationalism is that all exciting reasons presuppose instincts and affections, while justifying reasons presuppose a moral sense. An exciting reason is a motive which actually prompts a person to act; a justifying reason is one which grounds moral approval of the act. Hutcheson demonstrates that reason, unlike affection, cannot furnish an exciting motive, and that there can be no exciting reason previous to affection. Reason does of course play a role in our moral life, but only as helping to guide us to an end antecedently determined by affection, in particular the affection of universal benevolence. On this basis, an act can be called ‘reasonable’, but this is not a point on the side of the rationalists, since they hold that reason by itself can motivate, and in this case it is affection, not reason that motivates, that is, that gets us doing something rather than nothing.