Years ago, a lady friend explained to me that, in some cases, it's pointless to argue with someone who's taking an idiotic position because, as she said, "Some people are actually too stupid to know how stupid they are." And she was right, you know.
It's one thing to try to have a conversation with someone who's just a bit dense but who at least understands that they're a bit dense. It's quite another to sit there and listen, slack-jawed, to someone who's almost indescribably ignorant but has absolutely no comprehension of his (or her) own stupidity. It's truly breathtaking and, finally, there's scientific evidence as to how they got that way:
Scientific conclusion: Stupid people make us dumber.
Go. Read. Enjoy.