THE BEHAVIORAL SCIENCES have made startling advances into understanding how people are predictably irrational. For over a decade, their findings have been robust enough to shape public policy, design standards, and debates around tribal conflicts and self-sabotaging behavior. In his new book, Irrationality: A History of the Dark Side of Reason, philosopher Justin E. H. Smith barely engages with this literature on what are called “cognitive biases.” It’s a curious omission for a book with irrationality in its title.

Irrationality has unfulfilled potential, in other words. Smith is keenly aware that we’re living in an era when nothing seems to make sense. Virulent populism is on the rise. People proudly act against their best interests and contradict their professed values. With hateful contempt, they dismiss those who act and think differently. The authority of science and expertise are now passionately contested, with climate change widely denied, vaccines demonized, and alternative facts undercutting appeals to objectivity. Not only are proponents of the Enlightenment ridiculed as hypocritical frauds, but earlier hopes for the emancipatory promise of the internet have been soundly dashed. Even with massive amounts of information at our disposal, conspiracy theories endlessly circulate. And far from maturing into a respectful digital town square, social media is replete with trolling and computational propaganda, with advertising-dependent news outlets making matters worse by weaponizing clickbait in a war for our attention.

Smith has important things to say about all of these issues. Unfortunately, he’s mostly said them before in opinion pieces that are reprinted, more or less, in his book’s various chapters. While these interventions made for fine short-form contributions when they were originally published, consolidating them after-the-fact doesn’t create a whole that’s more edifying than the sum of its parts. Worse, much of Smith’s material on more classical topics will primarily be of interest to a narrow group of philosophical specialists. For everyone else, chapters devoted, for instance, to dreams, or replete with references to obscure historical figures like a 12th-century Danish Christian chronicler, or to texts like a philosophical poem written in 1692 by the Mexican nun Sor Juana Inés de la Cruz, will seem like esoteric diversions. In other words, the author fails to explain how his philosophical analogue to a sprawling-yet-idiosyncratic playlist illuminates current events. It seems we’re supposed to make the book cohere on our own, but the problem is that Smith doesn’t leave a trail of coherent breadcrumbs.

Murder He Wrote

Smith opens the book with a preamble that’s meant to serve as a parable for everything that follows. There, he recounts the story of the fifth-century murder of Hippasus. Most likely, this is a fictional tale or, in Smith’s words, a “legend” about something that “almost certainly never happened.”

Hippasus is said to belong to the ancient Pythagorean cult that made heady mathematical discoveries. Its members, according to Smith, became so zealous in espousing their view of the world as having an inherent rational structure, mathematically expressed through concepts like proportion and ratio, that they couldn’t come to grips with their discovery of irrational numbers. For example, they realized that when you calculate the diagonal of squares that have sides of equal length, you get results in a “decimal series that has no natural end.” This was a monstrous finding because it threatened fundamental Pythagorean convictions, suggesting that “mathematics is rotten at its core,” and, by extension, so is the world, because it’s putatively “built up from numbers.”

Poor Hipassus couldn’t keep his mouth shut. He blabbed about the secret of irrational numbers to outsiders. And so, in one version of the story, Hipassus’s fellow cult members violently killed him on a boat. In another version, the gods themselves perform the execution.

Smith treats this myth as a dialectical model for how rationality and irrationality recursively repeat through history in a trajectory that implicates our ancestors in antiquity as much as our contemporary societies. As Smith puts it:

This sequence of steps takes us out of the history of science and technology narrowly conceived, and into a social and political history whose chapters are often characterized by just this sort of dialectical motion: from commitment to an ideal, to the discovery within the movement of an ineradicable strain of something antithetical to that ideal, to, finally, descent into that opposite thing.

This is the history of rationality, and therefore also of the irrationality that twins it: exaltation of reason, and a desire to eradicate its opposite; the inevitable endurance of irrationality in human life, even, and perhaps especially — or at least especially troublingly — in the movements that set themselves up to eliminate irrationality; and, finally, the descent into irrational self-immolation of the very currents of thought and of social organization that had set themselves up as bulwarks against irrationality.

A Double-Threat Thinker

We can hazard a guess as to why Princeton University Press greenlit this book. On the one hand, Smith is proposing a deep dive into history — in order to uncover something not only lurking beneath the headlines but pervading the (mostly) Western history of ideas and their social and political manifestations. Revealing a hidden paradox is a grand ambition, something that perhaps only a learned philosophical scholar who cares about history and isn’t overly fixated on the present can pull off.

On the other hand, Smith also takes up du jour issues, like why President Trump appears to lack the “requisite clarity or maturity” to be “an anti-Enlightenment ideologue,” and how his presidential victory “was in no small measure” due to the alt-right co-opting satirical styles associated with Jerry Seinfeld and Howard Stern and producing humorous memes like Pepe the Frog.

In other words, Smith gives the impression that he’s a double threat.

He cites Erasmus’s In Praise of Folly (1511), William Barrett’s Irrational Man: A Study in Existential Philosophy (1958), and Michel Foucault’s Madness and Civilization: History of Insanity in the Age of Reason (1961), as models for his book. And he singles out Thomas Browne’s Pseudodoxia (1646) as a major inspiration. He drops erudite tidbits of knowledge from Socrates, Cicero, Aristotle, Immanuel Kant, and Sigmund Freud. And he doesn’t shy away from talking about manspreading and microaggression, as well as neo-Nazi violence in Charlottesville, Milo Yiannopoulos, and the Tea Party. He even takes a potshot at other philosophers for discussing preferred pronouns like he/she/they in supposedly intentionally contradictory ways that, he tells us, resemble the machinations of mystery cults.

But is this assemblage of material actually illuminating? Yes, but only sometimes. Page after page, I couldn’t figure out how the various threads of the book coherently hang together. Often, the writing seemed longwinded, pretentious, and self-indulgent.

Smith contributes to this impression in five ways. First, consider his main thesis, which is “that it is irrational to seek to eliminate irrationality, both in society and in our own exercise of our mental faculties.” But who, exactly, is making the case for an exhaustive purge of irrationality? To be sure, plenty of us wish that people behaved rationally more of the time. Some of us have wrongheaded convictions about how to accomplish this goal, for example naïvely mistaking ideology for ignorance and imagining that the best way to changes minds is to keep hammering home facts. But, this said, we know irrationality isn’t eradicable across the board; it would seem that Smith is trying to persuade a straw man opponent.

Second, Smith doesn’t try to justify his thesis with a formal argument that explicitly integrates the material from all of the chapters. Instead, he calls his diverse theoretical ideas and historical examples “an abundance of illustrations” that function as “instructive ornamentations.” I don’t know what this means. It sounds like a fancy way of saying that Smith had disparate material that he wrote at different times and for different audiences, threw it together, and, as a Hail Mary pass, hoped readers would find the collection of odds and ends illuminating.

Third, Smith makes plenty of seemingly random observations that are interesting in themselves. He fails, however, to tell us why they are significant. For example, he shows how pseudosciences can differ from one another. The founder of the Museum of Creation and Earth History located in Kentucky, he tells us, created an “alt-museum” that plays loose-and-fast with facts in order to mimic a scientific justification for the compatibility of paleontology, cosmology, and the creationism. Elsewhere, he juxtaposes young Earth creationism with flat Earth theory. Smith’s point is that creationists actually take their Darwinian opponents seriously, while the flat-earth folks don’t even bother to develop robust accounts of their views because their real interest is in convincing the masses that they have been tricked by elites into believing in hoaxes — like the “hoax” that NASA’s images of the Earth as seen from outer space are real. While I’m a fan of explanatory taxonomies, I like to know what value comes from considering them. Here, I’m unclear as to how knowing about this difference could, for example, lead to better conversations with adherents of either position. This confusion actually speaks to a deeper problem.

Smith doesn’t gesture to any solutions, however partial and imperfect, to the issues of our time, which is the book’s fourth shortcoming. Of course, plenty of worthy books diagnose rather than solve problems. But Smith simply isn’t interested in concretely sullying his hands, as it were, by trying, for instance, to improve legal or corporate policies, or enhance educational curricula, pivot politics, or resolve interpersonal conflict. Nor is he interested in redressing thought distortions that make for dangerous-for-us-all decisions. Smith might say that it’s wrong to look for solutions in a book with “history” in the title. But if history contains insights for the present, then surely they can be spelled out more clearly. To be sure, some historians are wary of giving their personal opinions, but Smith can’t pretend to suffer from this reservation, as I’ll explain.

Opining About Death

In fact, he offers plenty of opinions. Alas, many of them are less than persuasive, which is the fifth problem with his book. Consider his chapter on death, “The Impossible Syllogism: or, Death.”

As in much of the book, Smith takes a circuitous approach to the topic of how death, rationality, and irrationality are related. But he does make at least one direct point: he is, he tells us, incapable of “fully” grasping his mortality. As a consequence, “full rationality” is beyond his grasp: “moments of great pride, often […] born of panic” incline him to see himself as “immortal” and deem his “vain and trivial endeavors as all-important.” For him, this means he shares something fundamental with two people, one Leo Tolstoy’s bourgeois character Ivan Ilyich from the 1886 novella The Death of Ivan Ilyich, a classic overdetermined existential reference. And the other person: an American who subverts her own best interests by protesting against health-care proposals like Obamacare. While such a person might have couched her rejection as a defense of freedom from government control, or may have expressed the rebuke in racist terms (“How can I accept health insurance if it comes from a black president?”), underneath it all, Smith suspects, lies the possibility that she simply couldn’t “face up to a hard truth, either in her speaking or thinking” — namely, that like everyone else, she’s embodied and so will succumb to ill health and death.

I’m not sure if Smith believes that everyone is in denial about their own mortality. Or, if he believes some people more directly confront their deaths than others. Or if he would endorse the proposition that vast personal, social, and cultural differences shape what death means. These are open questions because Smith doesn’t address any of them in detail, nor does he consult the contemporary thanatology research, much less explain how, methodologically, we should determine whether someone genuinely is stuck in false consciousness when thinking about their finitude. Take the health-care protestor example. Yes, such people exist in the real world. But Smith’s analysis amounts to musing over a hypothetical case featuring a hypothetical subject hypothetically in denial about her mortality. Without sociological data, Smith gives us no basis for determining whether or not an actual person who says bigoted things about President Obama should be taken at her racist word. Sometimes a cigar is just a cigar and an apparent racist is the real deal.

In fact, Smith seems to contradict himself on the matter of evading death. In a prior chapter on jokes, Smith recounts how, back in 2015, he began arguing that “humor is the highest expression of freedom and the thing most to be defended in society.” It was the year employees at the offices of Charlie Hebdo, a satirical French weekly magazine, were killed by gunmen. To give us insight into his own sensibilities, he tells us he appreciates a gallows-humor, Charlie Hebdo cartoon depicting a dying musician surrounded by noise-making machines in a hospital framed by a headline suggesting the rock-and-roller “made a late-career turn to techno.”

Dare I say, I actually find this joke to be in bad taste. But more to the point, why should any of us charitably presume, as Smith does, that the cartoonist isn’t just being cruel? Smith defends the joke by asking, “Are we really expected to suppose that the cartoonist has no awareness that he himself could end up in a similar predicament soon enough?” Smith pretends this is a rhetorical question, but based on everything he says in the chapter on death he shouldn’t. If people are in as much denial about death as Smith himself contends, the most likely answer is yes.

In fact, there are lots of things Smith could have done better in his death chapter. One of them is to consider how near-death experiences affect how people think. Some people are traumatized and seek cognitive behavioral therapy to develop skills for better recognizing and coping with “cognitive distortions” like “catastrophizing.” But Smith is dismissive of such banal interventions, snarkily dismissing therapists as ill-equipped to handle patients confronting dilemmas involving “radically free choice between two incomparable conceptions of the good.” He might consider that a collective “we” could use a few therapeutic interventions that banally address our tendencies to distort and catastrophize. But that is too pragmatic for Smith. He prefers “ornamental” thinking, it seems.

Protesting Too Much Against Mass Culture

The history of philosophy offers a trove of insights that can help us make better decisions. But despite appearances, Smith clearly has no interest in directly addressing cognitive biases or helping us be better thinkers and decision-makers.

Perhaps the best way to characterize Irrationality is to see it in light of “It’s All Over,” a blog post that Smith wrote (reprinted at The Point Magazine) after submitting the completed manuscript. In it, he says he’s working out ideas that were only partially developed in the book. The main one is that, in Smith’s estimation, algorithms and people behaving like bots have created a claustrophobic culture. Software infers our interests and makes recommendations for what we should read, listen to, and watch by sussing out our behavioral patterns, reifying our sensibilities, and reducing human complexity to inferences gleaned from big data sets. Yes, we know this already. At the same time, Smith contends, people treat conversations, both on and offline, like polarized Twitter exchanges in which discourse is reduced to one of two options: momentary solidarity with like-minded others through virtue signaling; or, hostile, knee-jerk ripostes that translate claims into clichés. Sadly, we know this as well.

With defiant joy, Smith claims he’s sufficiently woke not to be hoodwinked by this Zeitgeist, contrasting, for example, his own ability to appreciate William S. Burroughs, the writer associated with the Beat Generation, to lamentable mass cultural sensibilities. The latter he associates with going to the multiplexes to see superhero movies, a genre he derides as “worthless” and “stunting.” And that’s the problem. Smith’s overly precious desire not to be identified with what’s trendy (or trending) but with what’s ornamental gets in the way of his writing a book that most of us can find illuminating.


Evan Selinger (@evanselinger) is a professor of philosophy at Rochester Institute of Technology.