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I’ve recently written—here, here, here, and here—that animals can be remarkably intelligent. And I'm not alone.
“Almost every week there is a new finding regarding sophisticated animal cognition, often with compelling videos to back it up,” writes Frans de Waal. He describes the rapidly accumulating data showing that "rats may regret their own decisions, that crows manufacture tools, that octopuses recognize human faces, and that special neurons allow monkeys to learn from each other’s mistakes. We speak openly about culture in animals and about their empathy and friendships. Nothing is off-limits anymore, not even the rationality that was once considered humanity’s trademark."
Time to carry this observation one step farther. Not only is animal rationality no longer off-limits, but it is also well established. At the same time, it is increasingly clear that rationality isn’t necessarily our trademark, because to a disconcerting extent, we aren’t that rational after all.
“What a piece of work is a man!” exulted Shakespeare’s otherwise melancholy Hamlet. “How noble in reason! How infinite in faculty! In form and moving how express and admirable! In action how like an angel! In apprehension how like a god!” Nearly two thousand years earlier, Aristotle maintained that happiness comes from the use of reason since that is the unique glory and power of humanity. Indeed, for the Greeks generally, reason distinguishes us from all other living things, and the life of reason is thus the greatest good to which human beings can aspire. So why doesn’t it attract more adherents these days?
For one thing, it may simply be that reason by definition is dry and cerebral, only rarely making inroads below the waist. Omar Khayyam made this trade-off uniquely explicit: “For a new Marriage I did make Carouse:/ Divorced old barren Reason from my Bed/ And took the Daughter of the Vine to Spouse.”
To be sure, excessive reason is easy to caricature. Thus, at one point in Jonathan Swift’s Gulliver’s Travels, our hero journeys to Laputa, whose (male) inhabitants are utterly devoted to their intellects: one eye focuses inward and the other upon the stars. Neither looks straight ahead. The Laputans are so cerebral that they cannot hold a normal conversation; their minds wander off into sheer contemplation. They require servants who swat them about the mouth and ears with special instruments, reminding them to speak or listen as needed. Laputans concern themselves only with pure mathematics and equally pure music. Appropriately, they inhabit an island that floats, in ethereal indifference, above the ground. Laputan women, however, are unhappy and regularly cuckold their husbands, who do not notice. The prime minister’s wife, for example, repeatedly runs away, preferring to live down on Earth with a drunk who beats her.
Thus presented, to reject reason seems, well, downright reasonable! Consider how rare it is for someone caught in the grip of strong emotion to be overcome by a fit of rationality, but how frequently events go the other way. After all, Blaise Pascal, who abandoned his brilliant study of mathematics to pursue religious contemplation, famously noted: "The heart has its reasons that reason does not understand." Or as 17th-century English churchman and poet Henry Aldrich pointed out in his Reasons for Drinking, often we make up our minds first, and find “reasons” only later: “If all be true that I do think/ There are five reasons we should drink:/ Good wine—a friend—or being dry —/ or lest we should be by and by —/ Or any other reason why!”
We may speak admiringly of Greek rationality, of the Age of Reason, and of the Enlightenment, yet it is far easier to find great writing—and even, paradoxically, serious thinking—that extols unreason, irrationality, and the beauty of “following one’s heart” rather than one’s head. Some of the most “rational” people have done just that.
Legend has it, for example, that when Pythagoras came up with his famous theorem, justly renowned as the cornerstone of geometry (that most logical of mental pursuits) he immediately sacrificed a bull to Apollo. Or think of Isaac Newton: pioneering physicist, both theoretical and empirical, he of the laws of motion and of gravity, inventor of calculus, and widely acknowledged as the greatest of all scientists. This same brilliant intellect wrote literally thousands of pages, far more than all his physics and mathematics combined, seeking to explicate the prophecies in the Book of Daniel.
Montaigne devoted many of his essays to a skeptical denunciation of the human ability to know anything with certainty. But probably the most influential of reason’s opponents was Jean-Jacques Rousseau, who claimed that “the man who thinks is a depraved animal.” Thereby speaking for what came to be the Romantic movement. But even earlier, many thinkers, including those who employed reason with exquisite precision, had been inclined to put it “in its place.” Hard-headed empiricist philosopher David Hume, for example, proclaimed in his Treatise of Human Nature that: “Reason is, and ought to be, the slave of the passions, and can never pretend to any other office than to serve and obey them.” Furthermore, when reason turns against the deeper needs of people, Hume argued, people will turn against reason.
Probably the most articulate, not to mention downright angry, denunciation of human reason, however, is found in the work of Fyodor Dostoyevsky, especially his novella, Notes From Underground, which depicts a nameless anti-hero: unattractive, unappealing, and irrational (although intelligent!). In angry contradiction to the utilitarians who argued that society should aim for the “greatest good for the greatest number” and that people can be expected to act in their own best interest, the Underground Man—literature’s first “anti-hero”—jeered that humanity can never be encompassed within a "Crystal Palace" of rationality. He may have a point: Certainly, unreason can be every bit as “human” as the Greeks believed rationality to be. You don’t have to be a Freudian, for example, to recognize the importance of the unconscious, which, like an iceberg, not only floats largely below the surface—and is thus inaccessible to rational control—but also constitutes much of our total mental mass.
It is one thing, however, to acknowledge the importance of unreason and irrationality, and quite another to applaud it, as the Underground Man does: “I am a sick man. … I am a spiteful man. I am a most unpleasant man.” The key concept for Dostoyevsky’s irrational actor is spite, a malicious desire to hurt others—including one’s self—without any compensating gain for the perpetrator. Consider the classic formulation of spite: “cutting off your nose to spite your face,” disfiguring yourself for “no reason.”
Significantly, spiteful behavior does not occur among animals. Even when an animal injures itself or appears to behave irrationally—gnawing off its own paw, killing and eating its offspring—there is typically a biological payoff: freeing oneself from a trap, turning one or more offspring (who under certain circumstances may be unlikely to survive) into calories for the parent. Spite, by contrast, is uniquely human.
The Underground Man goes on to rail against a world in which, to his great annoyance, two times two equals four. He claims, instead, that there is pleasure to be found in a toothache, and refers, with something approaching admiration, to Cleopatra’s alleged fondness for sticking golden pins in her slave-girls’ breasts to “take pleasure in their screams and writhing.”
As the Underground Man sees it, the essence of human-ness is living “according to our own stupid will … because it preserves for us what’s most important and precious, that is, our personality and our individuality.” He believes that people act irrationally because they stubbornly want to, snarling that, “If you say that one can also calculate all this according to a table, this chaos and darkness, these curses, so that the mere possibility of calculating it all in advance would stop everything and that reason alone would prevail—in that case man would be insane deliberately in order not to have reason, but to have his own way!”
Such sentiments are in no way limited to this most famous apostle of the dark Russian soul, or to European Romantics. Here is a poem from that quintessentially American writer, Stephen Crane, who gave us The Red Badge of Courage: “In the desert/ I saw a creature, naked, bestial/ Who, squatting upon the ground/ Held his heart in his hands/ And ate of it./ I said, ‘Is it good, friend?’/ ‘It is bitter, bitter,’ he answered;/ ‘But I like it/ Because it is bitter/ And because it is my heart.’”
David P. Barash is professor of psychology emeritus at the University of Washington; among his recent books is Through a Glass Brightly: using science to see our species as we really are (2018, Oxford University Press).
