  Even if one sympathizes with this objection, how to elucidate more systematically the normativity of convention remains unclear. It does not seem to be the normativity of morality, since someone who violates some convention of, say, etiquette or fashion need not thereby act immorally. Nor is it straightforwardly reducible to the normativity of instrumental rationality: many philosophers want to say that, other things being equal, one should conform to convention quite independently of whatever one’s beliefs and desires happen to be. (“You really ought to send a thank-you note.”) What is this mysterious brand of normativity, which apparently derives from neither morality nor instrumental rationality? That question is still a focus of active philosophical research.