  Hume’s position in ethics, which is based on his  empiricist theory of the mind,  is best known for asserting four theses: (1) Reason alone cannot be a motive to the will, but rather is the  “slave of the passions” (see  Section 3)    (2) Moral distinctions are not derived from reason (see  Section 4).  (3) Moral distinctions are derived from the moral sentiments: feelings of approval (esteem, praise) and disapproval (blame) felt by spectators who contemplate a character trait or action (see  Section 7).   (4) While some virtues and vices are natural (see  Section 13),  others, including justice, are artificial (see  Section 9).  There is heated debate about what Hume intends by each of these theses and how he argues for them. He articulates and defends them within the broader  context of his metaethics and his ethic of virtue and vice.