Jonathan Haidt’s new book makes a well-reasoned case against reason. It persuades that the power of persuasion is overrated. It opens minds to the near universality of closed minds. Does Haidt’s convincing theory affirm or rebut his argument? My brain hurts.

“Western philosophy has been worshipping reason and distrusting the passions for thousands of years,” the University of Virginia psychology professor writes. “There’s a direct line running from Plato through Immanuel Kant to Lawrence Kohlberg. I’ll refer to this worshipful attitude throughout this book as the rationalist delusion. I call it a delusion because when a group of people make something sacred, the members of the cult lose the ability to think clearly about it.”

Intellectuals confuse a more ideal state of affairs for the way things actually are—reason is more often than not rationalization, a justification for ideas developed not in the brain but in the gut. Haidt’s antecedent here is David Hume. Reason plays servant to man’s whims. Man forces the facts to fit his beliefs rather than the reverse. It’s no wonder that ideas that work marvelously in our minds fail miserably when applied to the world outside our heads. How a theory makes us feel, not whether it works, is the most important prerequisite for our acceptance of it.

Were athletes to seek rule by the strong or models rule by the beautiful, intellectuals would clearly see naked self-interest masked as reason. But Haidt finds other smart people to be no more reasonable in their use of reason. Intellectuals seek rule by the intelligent. The Righteous Mind explains that the rationalist delusion is

the idea that reasoning is our most noble attribute, one that makes us like the gods (for Plato) or that brings us beyond the ‘delusion’ of believing in gods (for the New Atheists). The rationalist delusion is not just a claim about human nature. It’s also a claim that the rational caste (philosophers or scientists) should have more power, and it usually comes along with a utopian program for raising more rational children.

Intelligence is a virtue. So are prudence, integrity, humility, and courage. People who possess the first trait, but lack the latter ones, tend to downplay the importance of their weaknesses and inflate the importance of their strength. The limitations of intelligence are never as glaring as when highbrains advocate intelligence as the panacea for everything. But it is not the intelligence of Haidt’s fellow liberals that he indicts. It’s their morals.

Haidt helped devise a questionnaire that gauged moral views by eliciting test-taker responses to statements in five categories: care/harm, fairness/cheating, loyalty/betrayal, authority/subversion, and sanctity/degradation. Haidt likens these moral groupings to the five taste receptors of the tongue (sweet, sour, bitter, savory, salty). It turns out that liberal receptors failed to engage on questions of loyalty, authority, and sanctity. Conservatives, on the other hand, reacted to all five moral categories more or less equally. Haidt’s conclusion is that his fellow liberals are morally tone deaf. “Republicans understand moral psychology,” Haidt concedes. “Democrats don’t.”

It gets worse for liberals. Haidt and colleagues asked their subjects to answer their questionnaire as if they were liberals, as if they were conservatives, and as themselves. Liberals don’t know their political adversaries nearly as well as the right knows them. “The results were clear and consistent. Moderates and conservatives were most accurate in their predictions, whether they were pretending to be liberals or conservatives. Liberals were the least accurate, especially those who described themselves as ‘very liberal.’ The biggest errors in the whole study came when liberals answered the Care and Fairness questions while pretending to be conservatives.” Liberals see caricatures when they see conservatives.

The thesis may prove cathartic for Republican readers. But it’s more useful to Democrats. Candidates who harp on the gap between rich and poor and appeal to the public’s heartstrings to uplift the least among us—but don’t grasp the tug of the flag, the fear of disorder, and the revulsion against sexually debasing behavior—really don’t get why they lose. They don’t get the American people, or just about any other people for that matter. They’re WEIRD—as in Western, Educated, Industrial, Rich, and Democratic. Weirdoes are more like weirdoes in other countries than they are like their fellow countrymen. The author notes of his subjects in Philadelphia and two Brazilian cities that “the effect of social class was much larger than the effect of city. In other words, well-educated people in all three cities were more similar to each other than they were to their lower-class neighbors.”

Ironically, the values touted by WEIRD multiculturalists are prevalent nowhere but in their own backyards; the nationalism, religiosity, and puritanical values they deride are dominant in the cultures for which they urge tolerance. They mistake the value system of Western, educated, industrialized, rich, democratic peoples for the value systems of Third World, uneducated, agrarian, impoverished, oppressed peoples. Thus, they urge tolerance of cartoon versions of non-Westerners while condemning their very real moral compasses. On some level, this confusion reflects the deep desire of rich white people to have their outlook affirmed by poor colored people.

The cognitive dissonance inherent in this jumbled conception of the world is remarkable. One question Haidt posed to subjects shows how morally obtuse the WEIRD are: he asked about a man who buys a chicken at the supermarket to eat for dinner, but before turning on the oven, copulates in secret with the dead, presumably plucked and headless, animal. Is that wrong? Everybody thought so, save, predictably, the weirdoes. Who was hurt? The implication here is that there’s something obviously lacking in a moral barometer that registers wrong only in direct harm.

Our politics—right, left, and other-directional—is less clinical detachment than stadium homerism. Haidt observes, “Bumper stickers are often tribal badges; they advertise the teams we support, including sports teams, universities, and rock bands. The driver of the ‘Save Darfur’ car is announcing that he or she is on the liberal team.” Given the paucity of Red Sox fans switching their allegiance to the Yankees, the sports analogy doesn’t bode well for a politics open to persuasion. “People are quite good at challenging statements made by other people,” Haidt points out, “but if it’s your belief, then it’s your possession—your child, almost—and you want to protect it, not challenge it and risk losing it.”

Haidt maintains that there are genetic and other biologial reasons for this. He cites a study that claims that agreement with comforting political positions releases dopamine in the brain, thereby conditioning humans to conform to the group. He cites another study purporting to show that one’s place on the political spectrum is in large part genetically predetermined. The Righteous Mind explains, “We’re born to be righteous, but we have to learn what, exactly, people like us should be righteous about.” The righteous mind, then, is part nature, part nurture.

The author is that rare academic who presents complex ideas in a comprehensible manner. Repetition and aphorism keep the reader on path. Haidt boils down chapters into pithy, reappearing verses. “Intuitions come first, strategic reasoning second.” “There’s more to morality than harm and fairness.” “Morality binds and blinds.” It’s hard to get lost when the author stays on track even as he meanders through psychology, politics, biology, religion, philosophy, and other fields.

The Righteous Mind delivers power shots to every outlook save its author’s. Haidt writes that “my beloved topic of inquiry—moral psychology—is the key to understanding politics, religion, and our spectacular rise to planetary dominance.” A liberal or conservative ideologue might substitute his own worldview for “moral psychology.” If the irony is intentional, the author is awfully subtle about it. Do psychologists diagnosing “the righteous mind” suffer from the phenomenon, too?

Haidt occasionally inserts head-scratching non sequiturs into the text, such as the bizarre idea that the 1970s crime wave resulted not from a spike in the youth demographic or permissiveness in the criminal justice system, but from leaded gasoline. The psychology professor, when appealing to the hard sciences—or explaining conservatism after telling readers that he happened upon conservatism in a used book store a few years ago—occasionally stumbles outside of his bailiwick. His professed utilitarian ethics would seem sure to dull the five moral sensors if the mathematics of the greater good added up. And implicit in that moral taste-buds metaphor is the absolute claim that morals are relativistic matters of taste rather than unequivocal matters of right and wrong. But if the reader can get past these quirks and shortcomings, the core point—that reason inhibits the search for truth as much as it helps—  provokes and rings, well, true.

This book starts debates about the people who forever seek to end them. And with cable news an incessant reminder of our calcified politics, the idea that the human brain is hard-wired to rationalize rather than to seek the truth has numerous unwitting televangelists buttressing the argument at every hour of the day. Haidt argues that this phenomenon isn’t the work of Phil Griffin or Roger Ailes but of evolutionary psychology; the “righteous mind” is 4.6 billion years in the making. The book arrives not a moment too soon.

Daniel J. Flynn is the author of Blue Collar Intellectuals: When the Enlightened and the Everyman Elevated America.