Hume’s views about the relationship between virtue and voluntariness do much to explain one of the most controversial aspects of his theory of virtue: his view that the natural abilities should be incorporated into the virtues and vices (T 3.3.4; EM App 4). With respect to this issue he makes two key points. The first is that natural abilities (i.e., intelligence, imagination, memory, wit, etc.) and moral virtues more narrowly understood are “equally mental qualities” (T 3.3.4.1/606). Second, both of them “equally produce pleasure” and thus have “an equal tendency to produce the love and esteem of mankind” (T 3.3.4.1/606–07). In common life, people “naturally praise or blame whatever pleases or displeases them and thus regard penetration as much a virtue as justice” (T 3.3.4.4/609). (See, e.g., Hume’s sardonic observation at EM App. 4.5/315: “It is hard to tell...”) Beyond all this, as already noted, any distinction between the natural abilities and moral virtues cannot be based on the consideration that the natural abilities are for the most part involuntarily acquired, since this also holds true for the moral virtues more narrowly conceived. It is, nevertheless, Hume’s view that the voluntary/involuntary distinction helps to explain “why moralists have invented” the distinction between natural abilities and moral virtues. Unlike moral qualities, natural abilities “are almost invariable by any art or industry” (T 3.3.4.4/609). In contrast with this, moral qualities, “or at least, the actions that proceed from them, may be chang’d by the motives of rewards and punishments, praise and blame” (T 3.3.4.4/609). In this way, according to Hume, the significance of the voluntary/involuntary distinction is largely limited to our concern with the regulation of conduct in society. To confine our understanding of virtue and vice to these frontiers is, however, to distort and misrepresent its very nature and foundation in human life and experience. (For more on Hume’s views on virtue in relation to his position on free will see Russell, 2013.)