Foot was one of the philosophers responsible for the turn away from emotivism and prescriptivism among many Oxford philosophers of the nineteen-sixties and later. By complicating or denying a fact/value distinction, she found room for a sophisticated kind of ethical naturalism. This is a version of an Aristotelian ethic in which the nature of human beings is itself a determinant of their good. Her approach requires firm connections between virtue, rationality, and self-interest, and critics have doubted whether the liaisons are as firm as she needed. Works include numerous papers, the collection Virtues and Vices (1978) and her first actual book, Natural Goodness (2001).