The people who voted for Donald Trump were, like those who voted for Hillary Clinton, a varied lot. Some were long-standing Republicans who had doubts about Trump but even more doubts about the idea of another Democratic president. Others were upset about some particular policy that has, in fact, hurt them. But it seems that a great many were older white Christians who had no college education. When I read what some of these voters said about their choice, I find much of it, to oversimplify just a little, false. Something seemed odd about the way they came to hold beliefs with apparent high confidence when these beliefs fly in the face of both good evidence and expert opinion.
If my perception is correct, then I think that psychology can both explain part of what they are doing and provide an optimistic solution for the future, if only the long-term future. Specifically, they are not thinking very well, and the kind of thinking they are not doing is influenced by schooling and culture. I call it actively open-minded thinking, or AOT. The purpose of AOT is to avoid myside bias (also called confirmation bias). Myside bias is a tendency to think in a way that favors pet beliefs: beliefs based on intuition alone, beliefs that one wants to have, or beliefs that have resulted from indoctrination. AOT counteracts myside bias by being open to alternatives and fair in the use of evidence and arguments. Beyond openness and fairness, AOT looks actively for alternatives and reasons why pet beliefs might be wrong.
AOT is the only way to have justified confidence in our beliefs. If we do not check them in this way, we cannot distinguish beliefs that deserve our confidence from those that do not. If we impose such untested beliefs on others through our political behavior, we risk hurting them, in ways that deserve their censure. We are being poor citizens.
AOT is also the basis of expertise of the sort we can trust. Scientists deserve our attention because the very nature of science, as a group activity, is to look for alternatives and evidence. Scientists get credit for poking holes in conventional scientific wisdom, leading to gradual improvement (and sometimes not so gradual). Good journalists, by checking their facts before going public, do the same. That is the difference between, well, the New York Times and fake news. None of these institutions is perfect, but they are more likely to reach good conclusions than they would reach without critical reflection. If people understand AOT, they will understand how to evaluate sources. They do not have to think through everything by themselves, because they can trust others who know how to think well, and they can recognize when this is being done. It is thus important for people to understand AOT and why it helps, as well as being able to do it themselves, when needed.
People differ enormously in their understanding of AOT and in their tendency to do it, as opposed to displaying myside bias. For example, one manifestation of myside bias is "belief overkill", the tendency to think that all arguments point in the same direction, for example, the belief that genetically modified food has no benefits, only risks, or that it has no risks, only benefits. I have found that some people display this bias at almost every opportunity, while others do not show the effect at all -- they can recognize the down side of their opinion while still believing that the up side predominates. Similar individual differences are found in other manifestations of AOT.
Myside bias is thus not a necessary part of the human condition. Some cultural practices, such as the discouragement of certain kinds of curiosity in children, may even lead people to oppose AOT when they would otherwise do it naturally. Education in the U.S., especially college education, encourages AOT. Students who write papers that neglect arguments on the other side of their conclusion do not usually get A's, even if they write well otherwise. AOT is part of what it means to be a responsible scholar and a good student. People who oppose AOT may also stay away from higher education because they do not want to think this way. The correlation between Trump support and lack of higher education may have more than one explanation.
AOT is malleable. People can be taught to engage in it. It is part of what is called cognitive style, not the result of how the brain is "hard wired". It is related to cognitive skills, but not dependent on them. Although AOT is emphasized in college, even elementary schools encourage it, if only indirectly by teaching tolerance and openness to others who are different. Several studies have shown that it can be taught by explicit instruction, especially when the idea is explained. Understanding is important, as well as some practice combined with self-evaluation. One of the most impressive of these studies was reported in 1986 by David Perkins and his collaborators. He found that myside bias was reduced by a few weeks of explicit instruction, but not by participation in other activities such as a high-school debating team. The debating team emphasized winning the argument, as opposed to discovering the best conclusion.
AOT is not a new idea. John Stuart Mill, in "On liberty", provided perhaps its most eloquent defense, using different terms. John Dewey argued that education should teaching something like it. After World War II, psychologists tried to understand support for fascism by looking at the personality traits of its supporters. It reached similar conclusions about individual differences and the role of open-mindedness, although this tradition largely neglected the potential role of education. It is on this latter point where the most recent research provides reason for optimism, even in the darkest times.