Tolerance fails as a virtue, first of all, because it is in some ways demeaning to people. It is much better to speak of "respect" or "empathy." But that is precisely the problem. Common sense tells us that there are people who cannot and ought not to command our respect or empathy. We regard what they stand for as stupid, crazy, evil, or all three. To be respectful of them would be to abandon all moral sense, so that a completely tolerant person would be totally passive, without a moral center.