One of my favorite philosophical tenets is that people will agree with you only if they already agree with you. You do not change people’s minds.

Zappa frames persuasion as largely illusory: assent usually reflects preexisting beliefs rather than conversion. The remark aligns with his broader skepticism toward mass opinion, ideological conformity, and the idea that rational argument reliably changes entrenched views. Read this way, the “tenet” is less a counsel of despair than a warning about the limits of rhetoric—especially in politics, religion, and culture wars—where identity and prior commitments often outweigh evidence. It also implies a pragmatic stance: if minds rarely change, the more realistic goals are to clarify positions, entertain, provoke thought, or reach those who are already receptive rather than trying to “convert” opponents.