Sorting fact from fiction in statements by Donald Trump and members of his administration can be demoralizing and cringe-inducing. The ratio of untruths to truths is astonishing—and many of the lies seem almost pointlessly cruel.  Trump lies at a pace that’s puzzling. What conceivable purpose could this behavior serve? And why are his most transparent lies so enthusiastically parroted by his underlings? My aim in this article is not to engage in partisan lie-shaming, but rather to better understand human nature. Why do people—and especially large groups of people—spew and cling to falsehoods?  As we’ll see, the distinction between truth…