“Post-truth politics,” “alternative facts,” “fake news”: how disdainfully the phrases drop from leftist lips. As the liberal writer Wes Williams puts it, “Right-wing media use ‘alternative facts’ on an almost daily basis.”

In fact, all human beings subconsciously seek out data that sustain their prejudices. We see what we want to see, even in the most literal sense: In tests where words are slowly illuminated on a screen, we see the nice words before the ugly ones.