In this essay, I argue that Harry Frankfurt’s view of the domain of ethics is flawed. On Frankfurt’s view, what we care about falls outside the proper scope of ethics because we are bound to what we care about, not by the force of moral necessities, but by non-moral ‘volitional necessities’. I show, however, that being moved to care within the constraints of our volitional necessities requires meeting a moral obligation of self-honesty. Developing Kant’s idea of a duty to truthfulness, I show that the duty to truthfulness is a duty to self-honesty. I then contend that self-honesty is a moral duty because self-honesty is essential for self-respect. Thus, because we fulfill a moral obligation to ourselves in the course of caring about things within the constraints of our volitional necessities, what we care about is a moral matter within the domain of ethics.