Now, whenever two people disagree, each is committed to saying that the other’s view is false and that his arguments are unsound; that’s just what disagreement means, and no one should be upset at this. But Mr. Auth goes much further. He’s saying not only that his opponents are wrong and that their arguments are unsound, but also that his opponents in fact have no reasonable arguments at all. If they had reasonable arguments, even ultimately unsound ones, then Mr. Auth would have to admit that they could well disagree with him on the basis of such arguments. So Mr. Auth is making an extremely strong claim here: not only that he’s right and his opponents are wrong, but also that all reasonable people have to agree with him, and anyone who disagrees with him is, to that extent, unreasonable. . . .

Something I've often found in my life as well. I'm not just wrong, I'm a bad person, if I disagree. On the other hand, I'm always plesantly surprised at the number of people who are willing to sit down and have a reasonable discussion. Sometimes I find that I'm not reasonable at that point. The door goes both ways, I suppose.