>> "Calling someone a troll is an ad hominem. We aren't supposed to do that >> in the IETF. At least, not publicly."[1] > > No, it is not ad hominem. Ad hominem is an argument of the form 'Hitler was > a vegetarian, therefore vegetarians are NAZIs' No, that's not true at all. Your example is a different logical fallacy. "Hitler was a vegetarian. His idea is, therefore, wrong, because vegetarians don't have good ideas," is an ad hominem argument -- attacking the person, rather than the content. "This person is a troll, so we should pay no attention to what he says," is, absolutely, an ad hominem argument. Whether or not we absolutely prohibit ad hominem arguments is something I'll dodge for right now. But let's be sure we understand the difference between these: 1. "I don't like you, and your argument is wrong because [response that addresses the issues]." This might include an inappropriate personal attack, but it's not an ad hominem argument. 2. "I don't like you, so your argument is not worth listening to." This *is* an ad hominem argument, whether or not it includes name calling or other unflattering characterizations. Barry