Willful ignorance. The idea that because you're uneducated you don't have to be concerned with facts. Facts are facts assholes, they don't give a shit about your opinion.

Speaking of opinion, the idea that someone's opinion matters and/or somehow has an impact on the facts. Doesn't matter if you think the sky is red, the fact that you got 30 other idiots to agree with you just means there's 31 idiots who think the sky is red. It doesn't open up the fact that it's blue to debate.