What are moral virtues and what are the characteristics of mankind? I am reminded (by Langer et al.’s reply) of Hobbes’ rundown on man’s characteristics (too lazy to find quotes). He says humans are more or less equal in mental capacity - we reason, imagine, sense, etc. But we are quite different physically, some stronger than others and so forth. For Hobbes, this meant we need the state to be the authority (and monopoly on force), to sort out our unequal differences.
Langer and then nudawn follow Hobbes in a way, by saying we need to examine the material conditions within which people act to make moral determinations. If a democracy or republic, (material conditions which require thoughtful participation), then we ought to privilege intelligence, since it enhances the value of participation, and so improves the common lot.
For me, it helps to make moral determinations of actions rather than characteristics. An intelligent person who sits around and does nothing all day, is certainly different from an intelligent person who devotes their studies to curing cancer. The difference is in the action. And we make moral determinations of the actions based on an account of human good.