Rick Shenkman is the editor of HNN. His newest book is Political Animals: How Our Stone Age Brain Gets in the Way of Smart Politics (Basic Books, January 2016).

Excerpt from an interview in Politico:

Question:  There have been some high-profile lies this election season. The most recent that comes to mind is the story about the thousands of Muslims that were supposedly having tailgate-style parties celebrating after 9/11. In the book, you say, essentially, we’re OK with lies. Can you walk me through why we’re built not only for being deceptive, but also tolerating deception?

RS:  Trump’s supporters don’t particularly care whether he’s lying or not. Our brain doesn’t really care—I know that’s appalling. Our default position is we simply want to be right. 

This is why our brain rationalizes our actions even when they’re at variance with our principles—that’s what cognitive dissonance is all about. So Trump supporters—when they hear Donald Trump say thousands of Muslims celebrated 9/11, and that turns out to be a lie, that obviously creates a conflict. Our brain tries to get out of these types of conflict in any way it can. One of the standard ways is to discredit the messenger—we say the mainstream media is full of it, for example. That’s true for Hillary Clinton supporters and true for Donald Trump supporters. All of us, Republicans, Democrats, we are all afflicted with this inclination to believe what we believe, and it doesn’t matter what the facts say. It took 11 months before public opinion started going against Nixon during Watergate. 

By nature, human beings are meant to be believers. We aren’t skeptics. We believe, and only at the second step do we subject our beliefs to scrutiny—this is all based on research by Harvard psychologist Dan Gilbert. That inclines us to deceptive politicians: We are inclined to believe them unless we have a previous reason not to believe them. 

Question:  It’s not just buying other people’s lies, though, right? You also have the chimp story, about how lying comes naturally to us.

RS:  Human beings are deceivers by nature; you can’t go through the day without practicing some form of deception. 

How deep is this in human nature? 

When you read primate studies of chimpanzees, they show that chimpanzees are also by nature deceptive. Roger Fouts, a primatologist, was the first to teach chimps how to use sign language. One day, he sees that one of the chimpanzees he was studying had defecated in the middle of someone’s living room. He confronts Lucy, his chimp—they are using sign language—and she responds instantly, “It’s not me! It’s you!” And he says, “No it’s not me.” And then she blames it on a graduate student. And finally, after a heated exchange, she admits, “Yes, it was me,” and she turns sheepish. 

It’s more than likely our common ancestor was deceptive by nature, which is why humans and chimpanzees have that trait. We like to think we’ve created the ideal community by encouraging people to be honest; the problem with that is that one traitor can take advantage of everybody. That is what happens in an honest community. Cheaters have the run of the place. 

In order to protect against that, we have cheater detection software. It’s a very sophisticated: With most humans (except psychopaths, who don’t show signs), when someone is standing face-to-face with you and lying, they’re twitching, the pitch of their voice might increase, their use of language becomes less detailed—and our unconscious brains take over to identify them as a liar. 

The problem in politics today is that our candidates are not face-to-face with us. We’re seeing them on TV, so our cheater detection software doesn’t work so well.

Question:  But there’s also the problem of people just not caring when they hear the truth, right? You have a good story about Grover Cleveland …

RS:  Grover Cleveland had a wonderful reputation as a truth-teller—it’s one of the ways he made such a rapid ascension through the ranks to president. And so when it was leaked that he had had a cancerous tumor removed, despite a White House-coordinated cover-up that he had just had a toothache, the public didn’t care. The media told the truth and the public didn’t really care. Wonderful example of how our resistance to truth—we don’t want the truth. We want our version of the truth. 

There’s another side of this that politicians take advantage of. If politicians believe their own lies, they get away with it. It’s how they can get past the cheater detection software. A politician who is good at deception and really believes his own lies can really get away with lying—until he develops a reputation for lies. So, Donald Trump lies. But at some point he gets caught so many times that he develops a reputation for lies, and that’s when he’s got a problem....