When we should engage with those we disagree with? We sometimes dismiss particularly controversial speakers and ideas without bothering to engage critically with those speakers and ideas-without, say, taking time to figure out where any arguments for those controversial ideas go wrong. Jeremy Fantl argues that we can know that arguments for controversial ideas go wrong even without engaging critically with them or figuring out where they err. Further, when we know that some argument goes wrong, we sometimes shouldn't engage critically with that argument and, if we do engage, we shouldn't engage open-mindedly.