Today, above all days, my neighbors demonstrate some of their worst traits. Robin quotes a Nature article:

Humans are unique among animals in maintaining large, stable coalitions of unrelated individuals, strongly bonded by mutual trust. Humans evolved the cognitive tools to ... gauge others' reliability. ... They can emit and detect costly, hard-to-fake signals of commitment. ... When people proclaim their adherence to a particular faith, they subscribe to claims for which there is no evidence, and that would be taken as obviously wrong or ridiculous in other religions groups. This signals a willingness to embrace the group's particular norm for no other reason than that it is, precisely, the group's norm.

We feel a deep pleasure from realizing that we believe something in common with our friends, and different from most people. We feel an even deeper pleasure letting everyone know of this fact. This feeling is EVIL. Learn to see it in yourself, and then learn to be horrified by how thoroughly it can poison your mind. Yes evidence may at times force you to disagree with a majority, and your friends may have correlated exposure to that evidence, but take no pleasure when you and your associates disagree with others; that is the road to rationality ruin.

Though the specific context was a discussion of religion I think that it generalizes to all beliefs and associations. Politics, for example, is the same. Robin's words seem to say this too.

Rationality is improbable, and so not of great concern to me. Humans are not often rational and they don't seem to enjoy it much when they are. I doubt that much progress can be made in this so the real task is to seek limits to the harms such evil doers can do.

Elections, of course, are antithetical to this. Harm is magnified today. We have the unseemly spectacle of large numbers of humans subscribing to claims for which there is no evidence and taking great pleasure in shared irrationality.