Last week, President Trump explained to a crowd in Erie, Pennsylvania, how he decides which polls to trust. “I believe in polls,” he said. “Only the ones that have us up, because they’re the only honest ones. Other than that, they’re the fake news polls.” Trump half-grinned, and the crowd laughed. But Trump really does let his beliefs follow his biases. He accepts the word of dictators and police, not of women, immigrants, or elected European leaders. In this way, Trump’s statements of fact, which are useless as guides to the truth, are highly useful as guides to his prejudices.
To understand Trump, you have to start with a distinction drawn by psychologist Thomas Gilovich in his book, How We Know What Isn’t So. Gilovich explains that when we want to believe something, we ask ourselves whether, despite contrary evidence, we can believe it. When we don’t want to believe something, we ask whether, despite supporting evidence, we must believe it. Each of us sometimes cheats this way, alternating between the two standards. But Trump cheats constantly and spectacularly.
Consider his interview on Sunday’s edition of 60 Minutes. Under interrogation by Lesley Stahl, Trump defended autocrats against every accusation. Did the Saudi government kill journalist Jamal Khashoggi? “They deny it, and deny it vehemently,” said Trump. Did Russia interfere in the 2016 election? “They meddled, but I think China meddled too,” he said, adding: “China is a bigger problem.” (Trump refused to affirm Russia’s interference when he met with Vladimir Putin in Helsinki.) Is Kim Jong-un denuclearizing North Korea? “I do trust him, yeah, I trust him,” said Trump.
To these dictators, Trump applies the can-believe standard: Is it possible they’re telling the truth? If so, Trump believes them. But when the conversation turns from tyrants to climate change, Trump switches to the must-believe standard. Stahl asked Trump: “What about the scientists who say it’s worse than ever?” Trump replied, “You’d have to show me the scientists, because they have a very big political agenda.” An agenda of ecology makes your assertions suspect. An agenda of mass murder doesn’t.
When Trump doesn’t like allegations of conspiracy, he ridicules them. “Do you really think I’d call Russia to help me with an election?” he asked Stahl. (Fact check: In a televised press conference, Trump explicitly asked Russia to hack Hillary Clinton’s emails.) But Trump is happy to peddle conspiracy theories about people he doesn’t like. “The European Union was formed in order to take advantage of us on trade,” he told Stahl. (Fact check: It wasn’t.) He also suggested that the New York Times might have fabricated last month’s anonymous op-ed by a “senior official in the Trump administration” representing an internal “resistance.” Who needs evidence when it’s conceivable that your allegation might be true?
Confronted with evidence that challenges his beliefs, Trump retreats to agnosticism. Video shows Khashoggi going into the Saudi consulate in Istanbul. No video shows him coming out. From the moment Khashoggi disappeared, intelligence has indicated that the Saudi government targeted him. Did they kill him? “Nobody knows yet,” Trump told Stahl. What about satellite images that show North Korea continuing to build missiles? “We don’t really know,” Trump shrugged. What about all the people who have pleaded guilty or been convicted in the Russia investigation, often for hiding contacts with Russians? “It’s a very unfair investigation because there was no collusion of any kind,” Trump insisted. There’s always a definition or a standard of certainty that will let the president believe what he wants to.
When Trump thinks he has experts on his side, he exploits them. “We have scientists that disagree” with ominous climate assessments, he told Stahl. Trump couldn’t name the scientists—“people,” he called them twice, when Stahl asked who they were—but he invoked their authority anyway. Conversely, when experts disagree with Trump, as nearly all climate scientists do, he dismisses their expertise as fake, partisan, or overblown. Stahl asked Trump whether Defense Secretary James Mattis, a four-star general, had informed the president that NATO was designed to prevent a third world war. In reply, Trump told Stahl: “I know more about it than he does.”
In the face of causal arguments he doesn’t like, Trump reaches for counterfactual objections. Responding to Stahl’s simple observation—“I wish you could go to Greenland, watch these huge chunks of ice just falling into the ocean”—Trump cautioned, “You don’t know whether or not that would have happened with or without man.” When Stahl claimed that the Western alliance had “kept the peace for 70 years,” Trump again warned, “You don’t know that.” There’s always an alternate universe, free of NATO or industrial emissions, that could disprove an unwelcome hypothesis.
But when Trump likes a causal argument, he ignores alternate scenarios and equates sequence with consequence. “The day before I came in, we were going to war with North Korea,” he told Stahl. What was Trump’s evidence for that claim? Just an assertion: “I think it was going to end up in war.” Trump went on to declare that without his family separation policy, “people are going to pour into our country.” And he credited his nasty remarks about Christine Blasey Ford, delivered at a campaign rally in Mississippi, for Brett Kavanaugh’s confirmation to the Supreme Court. “Had I not made that speech, we would not have won,” Trump insisted.
There’s no objective way to decide which standard—can-believe or must-believe—should be applied to a particular proposition or piece of evidence. Nor does Trump’s pattern of switching between them tell us which of his beliefs are false. But the pattern tells us a lot about Trump. It tells us that when he’s applying the can-believe standard—for example, to Putin, Kim, and the “very fine people” who rallied in Charlottesville, Virginia, to defend Confederate statues—those are the people Trump likes. Conversely, when he’s applying the must-believe standard—to the birthplace of America’s first black president, for instance, or to women who claim to have been sexually assaulted—those are the people Trump doesn’t like. The way a man chooses to use his brain tells you everything about his heart. Believe it.