In other cases, Trump is flouting more uniform expert consensus in the name of common sense. It is common sense that the only way to keep people and drugs from crossing the Mexican border is to build a wall from ocean to gulf. But experts reject that, noting the physical impossibility of sealing some parts of the border and pointing out that unauthorized immigrants and illegal drugs get through the border by various measures—semi truck, for example. (Ironically, border crossings have declined sharply since Trump’s inauguration, offering evidence against the notion that illegal immigration can be controlled only with a wall.)

There’s not only an overwhelming scholarly consensus that the climate is warming because of human activity, but an increasing number of material phenomena—from flooding in Florida to droughts in California—show it. Yet Trump appeals to common sense, saying, for example, that a snowstorm in Washington disproves the idea of climate change.

It makes Trumpian common sense that if the president can intervene to stop the closing of a Carrier plant in Indiana, it’s good for workers. But experts warned that such interventions rarely produce lasting changes if companies think they can cut costs by moving production elsewhere. Given that the plant is still shipping jobs overseas and cutting positions even as it profits from a raft of tax incentives, the common sense has some serious flaws.

It makes Trumpian common sense that if you place high tariffs on foreign goods, it will benefit American industry, protect manufacturing, and help blue-collar workers. One can certainly find economists who will argue that targeted tariffs in specific cases are useful tools, or even that the United States ought to adopt a more protectionist stance overall. But they are also in the minority. Most experts point to the increased costs for American consumers and the risks of starting trade wars.

Common sense can be a useful corrective for experts, who are as fallible as any other group of humans—and sometimes need a gut check. And scientists are susceptible to their own form of common-sense-bias, dismissing novel findings that contradict established paradigms or the weight of the published literature because they just know they can’t be true. But scientists are working from a method that allows received wisdom to be challenged, debated, and ultimately overturned.

That’s precisely the sort of process that invocations of common sense are designed to short circuit, making it harder for new evidence to modify old ideas.

Meanwhile, common sense is plenty susceptible to error on its own. Take this riff from Trump in August 2016:

Another major issue in this race is foreign policy. Hillary Clinton has made one bad foreign policy decision after another. Beginning with the support for going to war in Iraq, and I opposed it so strongly. Nobody cared. I was a civilian, but I opposed it. I said you will have a total destabilization of the Middle East. It was such common sense and look what happened.

Trump was lying—he supported the Iraq war at the time, but turned against it as it went sour, just like Clinton did. And, in fact, just like most of the American public did. Gallup found that in March 2003, as the war began, three-quarters of Americans supported the war. In other words, “common sense” was in favor of the war—and just like Trump, Clinton, and plenty of foreign-policy experts, it was wrong.