Desire as a Way of Knowing What Is Good in the Ethics of J. S. Mill (and Some Other Philosophers)

John Stuart Mill asks in Utilitarianism how we know the first principles of morality. He answers that desire, which he compares to sensory faculties, is how we know that something is desirable. I suggest we take him at his word – desire is the faculty, or something very similar, of moral perception – and I give some provisional analysis of this idea. In assigning desire a role in moral knowledge, Mill connects to other philosophers who have done the same, including Aristotle and Boethius. Mill himself fails to give a thorough account of metaethics, but in considering desire as a faculty he adds an important epistemological component to the tradition of including desire in the account of moral knowledge. I suggest that Mill’s ideas can inform the ideas of others in the tradition, and vice versa. Finally, I suggest that this whole conversation might be able to inform contemporary discussions of desire.