A touchstone to determine the actual worth of an "intellectual" - find out how he feels about astrology.

Heinlein proposes a deliberately provocative “test” for whether someone deserves the label “intellectual”: their attitude toward astrology. The point is less about astrology itself than about intellectual humility and the policing of respectable opinion. By choosing a topic widely dismissed by educated elites, he highlights how quickly some people substitute social conformity and reflexive scorn for inquiry. Read this way, the line critiques a certain kind of status-driven rationalism—where being “smart” means signaling the right disbeliefs—while also inviting the reader to notice how cultural taboos can become shortcuts for judging others’ intelligence. It can also be taken as a warning that contempt is not the same as critical thinking.