When so many obviously intelligent and well-educated Americans claim that global warming is a “hoax”; when we seem obsessed with vilifying an entire, fourteen centuries-old religious tradition simply because of recent heinous actions of terrorists who profess to act in its name; when, nearly a century after the Scopes Trial, there is still significant public resistance to the theory of evolution, with one recent poll revealing that 34% of the population rejects evolution — over one third of the country! — and when voters elect a man so obviously unprepared and unfit to be president, I begin seriously to worry that we Americans are exhibiting greater and greater stupidity.

Let me be clear: By “stupidity” I do not mean a lack of knowledge, education, skill or savvy. Stupidity is not the same as ignorance or incompetence or folly (although it often leads to foolish behavior). I do not mean it as some immature, all-purpose playground insult. I want not to offend but to diagnose.

In that spirit, I offer a different, more philosophical definition: Stupidity is a kind of intellectual stubbornness. A stupid person has access to all the information necessary to make an appropriate judgment, to come up with a set of reasonable and justified beliefs and yet fails to do so. The evidence is staring them right in the face but it makes no difference whatsoever. They believe what they want to believe. Not only do they have no good reasons for thinking that what they believe is true — there are often good reasons for thinking that what they believe is false. They are not acting in a rational manner.

Of course, everyone is stupid sometime or other. We have all fallen headlong for some product because it looks cool or because some celebrity we like but who has zero expertise tells us he has one, despite there being no reason whatsoever for buying the item and maybe even good reasons not to buy it. We often make choices on the basis of emotions like hope, fear, love, envy, pride and anger — instead of reason. However, while other nations seem to be tackling the local and global problems we face head on, relying not so much on passion but on science and common sense, we seem as a nation to be acting stupidly. And in this regard we fail to live up to, and even betray, just those values that have informed our republic from its founding and to which we now so often merely pay lip service.

In many respects, America is, for better and for worse, heir to the intellectual revolution of seventeenth-century Europe. What characterized philosophy and science in the early modern period and represented a break from much of what went before is the concern to tailor theories to evidence, not to authority or tradition. Galileo, Descartes, Spinoza, Locke, Newton and others came up with explanations of the cosmos, of the world around them and of human nature and society not by appealing to what earlier thinkers (such as Plato and Aristotle) had said. Nor were they guided primarily by religious dogma. Rather, they took their lead from reason and experience. Whether they proceeded according to the logic of deduction or through the critical collection and analysis of data, what the modern scientific method they developed consists in is the testing of theories according to what reason allows and what empirical evidence supports. A rational person only believes what the evidence warrants him in believing; he does not merely accept things on faith; and when the evidence falsifies his beliefs, he abandons them. It is irrational — stupid — to hold onto beliefs when they are plainly contradicted by the evidence.

These early modern thinkers were not irreligious men; in fact, many of them were deeply pious, devoted to the Catholic or Reformed church. The alleged “war” in the early Enlightenment between science and religion is a gross exaggeration. But for Descartes and his intellectual colleagues, philosophical, scientific, even moral and political truth and progress was a matter of rational and empirical inquiry, not fealty to authority.

The problem is not that the people who don’t believe in climate change or who choose to not vaccinate their children or who deny evolution by natural selection are necessarily uninformed (although many of them are, and a good deal of what passes for “information” these days comes from highly suspect sources). Rather, it is that in the face of relevant information they have refused to adjust or abandon their beliefs accordingly. They are making a crucial decision not on the basis of what Descartes called “clear and distinct” evidence, but on prejudice, hearsay and, of course, those passions of hope and fear. An article in the New York Times recently said that “an aversion to scientific findings continues to shape American public policy.” What the writer failed to note is how much that aversion to scientific reasoning informs the decisions people make in their daily lives.

What is the solution to our creeping national stupidity? Learning how to gain more information from a variety of certifiably reliable sources is an important first step. But what the American public really needs are lessons in how to be rational, how to assess that information — distinguishing between real evidence and fake evidence — and end up believing only what one is justified in believing. We could use more lessons on what it means to be rational and how to be epistemologically responsible citizens who are familiar with the difference between a valid and invalid argument, and who know an unjustified belief when they see one.

Changing people’s cognitive behavior will not be easy; it may even be a fool’s errand. By young adulthood, we naturally become stuck in our ways of forming and abandoning beliefs. I like to think that the key lies in more philosophy, and more of the humanities overall. Most people, if they study philosophy at all, do so only in college — typically to fulfill some distribution requirement. But what if we start exposing young people to philosophy well before they become undergraduates? There is no reason why high school students, even children in elementary school, cannot absorb the basic lessons of rationality and critical thinking that come from studying the great thinkers of the past and of today, and the problems in ethics, politics, epistemology, metaphysics and aesthetics that they address. If there is a cure for stupidity, I am convinced that this is it. I hope I’m proven right.

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