I first heard about Rationality, the latest book from linguist Steven Pinker, from his publisher, offering to send me a review copy. Pinker has lots of interesting things to say, so I was happy to take a look. I’ve had disagreements with him in the past, but it’s always been cordial, (see here, here, and here), and he’s always shown respect for my research—indeed, if I do what Yair calls a “Washington read” of Pinker’s new book, I find a complimentary citation to me—indeed, a bit too complimentary, in that he credits me with coining the phrase “garden of forking paths,” but all I did was steal it from Borges. Not that I’ve ever actually read that story; in the words of Daniel Craig, “I like the title.” More generally, I appreciate Pinker’s willingness to engage with criticism, and I looked forward to receiving his book and seeing what he had to say about rationality.

As with many books I’m called upon to review, this one wasn’t really written for me. This is the nature of much of nonfiction book reviewing. An author writes a general-audience book on X, you get a reviewer who’s an expert on X, and the reviewer needs to apply a sort of abstraction, considering how a general reader would react. That’s fine; it’s just the way things are.

That said, I like the book, by which I mean that I agree with its general message and I also agree with many of the claims that Pinker presents as supporting evidence.

Pinker’s big picture

I’ll quickly summarize the message here. The passage below is not a quote; rather, it’s my attempt at a summary:

Humans are rational animals. Yes, we are subject to cognitive illusions, but the importance of these illusions is in some way a demonstration of our rationality, in that we seek reasons for our beliefs and decisions. (This is the now standard Tversky-Kahneman-Giverenzer synthesis; Pinker emphasizes Gigerenzer a bit less than I would, but I agree with the general flow.) But we are not perfectly rational, and our irrationalities can cause problems. In addition to plain old irrationality, there are also people who celebrate irrationality. Many of those celebrators of irrationality are themselves rational people, and it’s important to explain to them why rationality is a good thing. If we all get together and communicate the benefits of rationality, various changes can be made in our society to reduce the spread of irrationality. This should be possible given the decrease in violent irrationality during the past thousand years. Rationality isn’t fragile, exactly, but it could use our help, and the purpose of Pinker’s book is to get his readers to support this project.

There’s a bit of hope there near the end, but some hope is fine too. It’s all about mixing hope and fear in the correct proportions.

Chapter by chapter

A few years ago, I wrote that our vision of what makes us human has changed. In the past, humans were compared to animals, and we were “the rational animal”: our rationality was our most prized attribute. But now (I wrote in 2005) the standard of comparison is the computer, we were “the irrational computer,” and it was our irrationality that was said to make us special. This seemed off to me.

Reading chapter 1 of Pinker’s book made me happy because he’s clearly on my side (or, maybe I should say, I’m on his side): we are animals, not computers, and it’s fair to say that our rationality is what makes us human. I’m not quite sure why he talks so much about cognitive illusions (the availability heuristic, etc.), but I guess that’s out of a sense of intellectual fairness on his part: He wants to make the point that we are largely rational and that’s a good thing, and so he clears the deck by giving some examples of irrationality and then explaining how this does not destroy his thesis. I like that: it’s appealing to see a writer put the evidence against his theory front and center and then discuss why he thinks the theory still holds. I guess I’d only say that some of these cognitive illusions are pretty obscure—for example I’m not convinced that the Linda paradox is so important. Why not bring in some of the big examples of irrationality in life: on the individual level, behaviors such as suicide and drug addiction; at the societal levels, decisions such as starting World War 1 and obvious misallocations of resources such as financing beach houses in hurricane zones? I see a sort of parochialism here, a focus on areas of academic psychology that the author is close to and familiar with. Such parochialism is unavoidable—I write books about political science and statistics!—but I’d still kinda like to see Pinker step back and take a bigger perspective. In saying this, I realize that Pinker gets this from both sides, as other critics will tell him to stick to his expertise in linguistics and not try to make generalizations about the social world. So no easy answer here, and I see why he wrote the chapter the way he did, but it still leaves me slightly unsatisfied despite my general agreement with his perspective.

I liked most of chapter 2 as well: here Pinker talks about the benefits of people taking a rational approach, both for themselves as individuals and for society. I don’t need much convincing here, but I appreciated seeing him make the case.

Pinker writes that “ultimately even relativists who deny the possibility of objective truth . . . lack the courage of their convictions.” I get his point, at least sometimes, for example consider the people who do double-blind randomized controlled trials of intercessory prayer—they somehow think that God has the ability to cause a statistically significant improvement among the treatment group but that He can’t just screw with the randomization. On the other hand, maybe Pinker is too optimistic. He writes that purported “relativists” would not go so far as to deny the Holocaust, climate change, and the evils of slavery—but of course lots of people we encounter on the internet are indeed relativistic enough in their attitudes to deny these things, and they appear to be happy to set aside logic and evidence and objective scholarship to hold beliefs that they want to believe (as Pinker actually notes later on in chapter 10 of his book). Sometimes it seems that the very absurdity of these beliefs is part of their appeal: defending slavery and the Confederacy, or downplaying the crimes of Hitler, Stalin, Mao, etc., is a kind of commitment device for various political views. I guess climate change denial (and, formerly, smoking-cancer denial) is more of a mixed bag, with some people holding these views as a part of their political identity and others going with the ambiguity of the evidence to take a particular position. Belief in intercessory prayer is a different story because, at least in this country, it’s a majority position, so if you have a generally rational outlook and you also believe in the effectiveness of intercessory prayer, it makes sense that you’d try your best to fit it into your rational view of the world, in the same sense that rational rationalizers might try to construct rationales for fear, love, and other strong emotions that aren’t particularly rational in themselves.

Elsewhere I think Pinker’s too pessimistic. I guess he doesn’t hear that complaint much, but here it is! He writes: “Modern universities—oddly enough, given that their mission is to evaluate ideas—have been at the forefront of finding ways to suppress opinions, including disinviting and drowning out speakers, removing controversial teachers from the classroom, revoking offers of jobs and support, expunging contentious articles from archives, and classifying differences of opinion as punishable harassment and discrimination.” I guess I’m lucky to be at Columbia because I don’t think they do any of that here. I’ll take Pinker at his word that these things have happened at modern universities; still I wouldn’t say that universities “at the forefront of finding ways to suppress opinions,” just because their administrations sometimes make bad decisions. If universities are at the forefront of finding ways to suppress opinions, where does that put the Soviet Union, the Cultural Revolution, and other such institutions that remain in living memory? I agree that we should fight suppression of free speech, but let’s keep things in perspective and save the doomsaying for the many places where it’s appropriate!

There was another thing in chapter 2 that didn’t ring true to me, but I’ll get to it later, as right here I don’t want these particular disagreements to get in the way of my agreement with the main message of the chapter, which is that rational thinking is generally beneficial in life and society, even beyond narrow areas such as science and business.

I have less to say about chapters 3 through 9, which cover logic, probability, Bayesian reasoning, expected utility, hypothesis testing, game theory, and causal inference. He makes some mistakes (for example, defining statistical significance as “a Bayesian likelihood: the probability of obtaining the data given the hypothesis”), but he does a pretty good job at covering a lot of material in a small amount of space, and I was happy to see him including two of my favorite examples: the hot hand fallacy fallacy explained by Miller and Sanjurjo, and Gigerenzer’s idea of expressing probabilities as natural frequencies. I’m not quite sure how well this works as a book—to me, it sits in the uncanny valley between a college text and a popular science treatment—but I’m not the target audience here, so who am I to say.

Just one thing. At one point in these chapters on statistics, Pinker talks about fallacies that have contributed to the replication crisis in science (that’s where he mentions my forking-paths work with Eric Loken). I think this treatment would be stronger if he were to admit that some of his professional colleagues have been taken in by junk science in its different guises. There was that ESP study published by one of the top journals in the field of psychology. There was the absolutely ridiculous and innumerate “critical positivity ratio” theory that, as recently as last year, was the centerpiece of a book that was endorsed by . . . Steven Pinker! There was the work of “Evilicious” disgraced primatologist Marc Hauser, who wrote a fatuous article for the Edge Foundation’s “Reality Club” . . . almost a decade before Harvard “found him guilty of scientific misconduct and he resigned” (according to wikipedia). I think that including these examples would be a freebie. Admitting that he and other prominent figures in his field were fooled would give more of a bite to these chapters. Falling for hoaxes and arguments with gaping logical holes is not just for loser Q followers on the internet; it happens to decorated Harvard professors too.

The final two chapters of the book return to the larger theme of the benefits of rationality. Chapter 10 leads off with a review of covid science denial, fake news, and irrational beliefs. Apparently 32% of Americans say they believe in ghosts and 21% say they believe in witches. The witches thing is just silly, but covid denial has killed people, and climate change denial has potentially huge consequences. How to reconcile this with the attitude that people are generally rational? Pinker’s answer is motivated reasoning—basically, people believe what they want—and that most of these beliefs are in what he calls “the mythology zone,” beliefs such as ghosts and witches that have no impact on most people’s lives. He argues that “the arc of knowledge is a long one, and it bends toward rationality.” I don’t know, though. I feel like the missing piece in his story is politics. The problem with covid denial is not individual irrationality; it’s the support of this denialism by prominent political institutions. In the 1960s and again in recent years, there’s been widespread concern about lawlessness in American politics. When observers said that the world was out of control in the 1960s, or when they say now that today’s mass politics are reminiscent of the 1930s, the issue is not the percentage of people holding irrational beliefs; it’s the inability of traditional institutions to contain these attitudes.

Getting to details: A couple places in his book, Pinker refers to the irrationality of assuming that different groups of people are identical on average in “socially significant variables” such as “test scores, vocational interests, social trust, income, marriage rates, life habits, rates of different types of violence.” As Woody Guthrie sang, “Some will rob you with a six-gun, and some with a fountain pen.” Fine. I get it. Denying group differences is irrational. But it’s funny that Pinker doesn’t mention irrationality in traditional racism and sexism, the belief that women or ethnic minorities just can’t do X, Y, or Z. These sorts of prejudices are among the most famous examples of irrational thinking. Irrationalities bounce off each other, and one irrationality can be a correction for another. Covid denialism and climate change denialism, as unfortunate and irrational as they are, can be seen as reactions to the earlier irrationality of blind trust in our scientific overlords, with these reactions stirred up by various political and media figures.

At one point Pinker writes, “Rationality is disinterested. It is the same for everyone everywhere, with a direction and momentum of its own.” I see the appeal of this Karenina-esque statement, but I don’t buy it. Rationality is a mode of thinking, but the details of rationality change. For example, nowadays we have Bayesian reasoning and the scientific method. Aristotle, rational as he may have been, didn’t have these tools. In his concluding chapter, Pinker seems to get this, as he talks about the ever-expanding bounds of rationality during the past several centuries. I guess the challenge is that people may be more rational than they used to be, but in the meantime our irrationality can cause more damage. Technology is such that we can do more damage than ever before. What’s relevant is not irrationality, but its consequences.

Now that I’ve read the whole book, let me try to summarize the sweep of Pinker’s argument. It goes something like this:

Chapter 1. It is our nature as humans for our beliefs and attitudes to have a mix of rationality and irrationality. We’re all subject to cognitive illusions while at the same time capable of rational reasoning.

Chapter 2. Rationality, to the extent we use it, is a benefit to individuals and society.

Chapters 3-9. Rationality ain’t easy. To be fully rational you should study logic, game theory, probability, and statistics.

Chapter 10. We’re irrational because of motivated reasoning.

Chapter 11. Things are getting better. Rationality is on the rise.

The challenge is to reconcile chapter 1 (irrationality is human nature) with chapters 3-8 (rationality ain’t easy) and 10 (rationality is on the rise). Pinker’s resolution, I think, is that science is progressing (that’s all the stuff in chapters 3-8 that can help the readers of his book become more rational in their lives and understand the irrationality of themselves and others) and society is improving. Regarding that last point, he could be right; at the same time, he never really gives a good reason for his confidence that we don’t have to be concerned about the social and environmental costs of increasing political polarization, beyond a vague assurance that “The new media of every era open up a Wild West of apocrypha and intellectual property theft until truth-serving counteremasures are put into place” and then some general recommendations regarding social media companies, pundits, and deliberative democracy, with the statement (which I agree with) that rationality “is not just a cognitive virtue but a moral one.” As the book concludes, Pinker alternates between saying that we’re in trouble and we need rationality to save us, and that progress is the way of the world. This is a free-will paradox that is common in the writings of social reformers: everything is getting better, but only because we put in the work to make it so. The Kingdom of Heaven has been foretold, but it is we, the Elect, who must create it. Or, to put it in a political context, We will win, but only with your support. This does not mean that Pinker’s story is wrong: it may well be that rationality will prevail (in some sense) due to the effort of Pinker and the rest of us; I’m just saying that his argument has a certain threading-the-needle aspect.

Still and all, I like Pinker’s general theme of the complexity and importance of rationality, even if I think he focuses a bit too much on the psychological aspect of the problem and not enough on the political.

Parochialism and taboo

One unfortunate feature of the book is a sort of parochialism that privileges recent academic work in psychology and related fields. For example this on page 62: “Can certain thoughts be not just strategically compromising but evil to think? This is the phenomenon called taboo, from a Polynesian word for ‘forbidden.’ The psychologist Philip Tetlock has shown that taboos are not just customs of South Sea islanders but active in all of us.” And then there’s a footnote to research articles from 2000 and 2003.

That’s all well and good, but:

1. No way that Tetlock or anybody else has shown that an attitude is “active in all of us.” At best these sorts of studies can only tell us about the people in the studies themselves, but, also, this evidence is almost always statistical, with the result being that average behavior is different under condition A than under condition B. I can’t think of any study of this sort that would claim that something occurs 100% of the time. Beyond this, there do seem to be some people who are not subject to taboos. Jeffrey Epstein, for example.

2. If we weaken the claim from “taboos are active in all of us” to “taboos are a general phenomenon, not limited to some small number of faraway societies,” then it seems odd to attribute this to someone writing in the year 2000. The idea of taboos being universal and worth studying rationally is at least as old as Freud. Or, if you don’t want to cite Freud, lots of anthropology since then. Nothing wrong with bringing in Tetlock’s research, but it seems a bit off, when introducing taboos, to focus on obscure issues such as “forbidden base rates” or attitudes on the sale of kidneys rather than the biggies such as taboos against incest, torture, etc.

I’ve disagreed with Pinker before about taboos, and I think my key point of disagreement that sometimes he labels something a “taboo” that I would just call a bad or immoral idea. For example, a few years ago Pinker wrote, “In every age, taboo questions raise our blood pressure and threaten moral panic. But we cannot be afraid to answer them.” One of his questions was, “Would damage from terrorism be reduced if the police could torture suspects in special circumstances?” I don’t think it’s “moral panic” to be opposed to torture; indeed, I don’t think it’s “moral panic” for the question of torture to be taken completely off the table. I support free speech, including the right of people to defend Jerry Sandusky, Jeffrey Epstein, John Yoo, etc etc., and, hey, who knows, someone might come up with a good argument in favor of their behavior—but until such an argument appears, I feel no obligation to seriously consider these people’s actions as moral. Pinker might call that a taboo on my part; I’d call this a necessary simplification of life, the same sort of shortcut that allows me to assume, until I’m shown otherwise, that dishes when dropped off the table will fall down to the floor rather than up to the ceiling. Again, Pinker’s free to hold is own view on this—I understand that since making the above-quoted statement he’s changed his position and is now firmly anti-torture—; my point is that labeling an attitude as “taboo” can itself be a strong statement.

Another example is that Pinker describes it as “a handicap in mental freedom” to refuse to answer the question, “For how much money would you sell your child?” Here he seems to be missing the contextual nature of psychology. Many people will sell their children—if they’re poor enough. I doubt many readers of Pinker’s book are in that particular socioeconomic bracket; indeed, in his previous paragraph he asks you to “try playing this game at your next dinner party.” I think it’s safe to say that if you’re reading Pinker’s book and attending dinner parties, that there’s no amount of money for which you’d sell your child. So the question isn’t so much offensive as silly. My guess is that if someone asks this at such a party, the response would not be offense but some sort of hypothetical conversation, similar to if you were asked whether you’d prefer invisibility or the power of flight. Or maybe Pinker hangs out with a much more easily-offended crowd than I do. On the other hand, what about people who actually sold their children, or the equivalent, to Jeffrey Epstein? Pinker’s on record as saying this is reprehensible. How does this line up with his belief that it’s “a handicap in mental freedom” to not consider for how much money you would sell your child?

This example points to a sort of inner contradiction of Pinker’s reasoning. On one hand, he’s saying we all have taboos. I guess that includes him too! He’s also saying that we live in a society where there are all sorts of things we can’t talk about, not just torture and the selling of children and the operation of a private island for sex with underage women, but also organ donation, decisions of hospital administrators, and budgetary decisions. On the other hand, he’s writing for an audience of readers who, if they don’t already agree with him, are at least possibly receptive to his ideas—so they’re not subject to these taboos, or at least maybe not. This gets back to the question of what Pinker’s dinner parties are like: is it a bunch of people sitting around the table talking about the potential benefits of torture, subsidized jury duty, and an open market in kidneys; or a bunch of people all wanting to talk about these things but being afraid to say so; or a bunch of people whose taboos are so internalized that they refuse to even entertain these forbidden ideas? You can see how this loops back to my first point above about that phrase “active in all of us.” Later on, Pinker says, “It’s wicked to treat an individual according to that person’s race, sex, or ethnicity.” “Wicked,” huh? That seems pretty strong! Torture or selling your child are OK conversation topics, but treating men different than women is wicked? I honestly can’t figure out where he draws the line. That’s ok—there’s no reason to believe we’re rational in what bothers us—but then maybe he could be a bit more understanding about those of us think that torture is “wicked,” rather than just “taboo.”

Also I don’t quite get when Pinker writes that advertisers of life insurance “describe the policy as a breadwinner protecting a family rather than one spouse betting the other will die.” This just seems perverse on his part. When I bought life insurance, I was indeed doing it to protect my family in the event that I die young. I get it that you could say that mathematically this is equivalent to my wife betting that I would die, but really that makes no sense, given that I was the one paying for the insurance (so she’s not “betting” anything) and, more importantly, the purpose of the insurance was not to gamble but to reduce uncertainty. It would make more sense to say I was “hedging” against the possibility that I would die young. Here it seems that Pinker wants to anti-euphemize, to replace an accurate description (buying life insurance to protect one’s family) by an inaccurate wording whose only virtue is harshness.

Had I written this book, I would’ve emphasized slightly different things. As noted above, it seems strange to me that, when talking about irrationality, Pinker focuses so much on irrational beliefs rather than on irrational actions. At one level, I understand: the belief is father to the action. But it’s the actions that matter, no? I guess one reason I say this is my political science background. For example, the irrational action of funding housing construction in flood zones can be explained in part through various political deals and subsidies. Spreading better understanding of climate change should help, but it’s not clear that individual irrationality is the biggest problem here, and I’m concerned that Pinker is falling into an individualistic trap when studying society. To take a more positive example, cigarette smoking rates are much lower than they were a half-century ago. I would attribute this not to an increase in rationality or Odyssean self-control but rather to notions of fashion and coolness of which Pinker seems so dismissive. Smoking used to be cool, it’s no longer. I remember 20 years ago when NYC banned smoking in restaurants and bars; various pundits and lobbying organizations declared that this was a horrible infringement on liberty, that the people would rise up, etc. . . none of those things happened. They banned smoking and people just stopped smoking indoors. I guess that did induce some Odyssean self-control among smokers, so I’m not saying these individualistic behavioral concepts are useless, just that they’re not the whole story, and indeed sometimes they don’t seem to be the most important part of the story.

But that’s not really a criticism of Pinker’s book, that I would’ve written something different. It’s a limitation of his story, but all stories have limitations.

Big hair

One thing I found charming about the book, but others might find annoying, is the datedness of some of its references and perspectives. Chapter 1 reads as if it was written in the 1980s, back when the work of Tversky, Kahneman, and Gigerenzer was new. (I was going to say “new and exciting,” but that would be misleading: yes, their work was new and exciting in the 1980s, but it remains exciting even now, long after it was new.) Chapter 2 begins, “Rationality is uncool. To describe someone with a slang word for the cerebral, like nerd, wonk, geek, or brainaic, is to imply they are terminally challenged in hipness. I guess there’s always the possibility that he’s kidding, but . . . things have changed in the past 40 years, dude! In recent years, lots of people have been proud to be called nerds, wonks, or geeks; if anything, it’s “hipsters” who are not considered to be so cool. Pinker supports his point with quotes from Talking Heads, Prince, and . . . Zorba the Greek? That’s a movie from 1964! Later he refers to Peter, Paul and Mary (or, as he calls them, “Peter, Paul, and Mary”—prescriptive linguist that he is). When it comes to basketball, his go-to example is Vinnie Johnson from the 1980s Pistons. OK, I get it, he’s a boomer. That’s cool. You be you, Steve. But it might be worth not just updating your cultural references but considering that the culture has changed in some ways in the past half-century. In that same paragraph as the one with Zorba, Pinker describes “postmodernism” and “critical theory” as “fashionable academic movements.” I’m sure that there are professors still teaching these things, but no way that postmodernism and critical theory are “fashionable.” It’s been close to 40 years since they were making the headlines! You might as well label suspenders, big hair, and cocaine as fashionable. I half-expected to hear him talk about “yuppies” and slip in an Alex P. Keaton reference.

Review of reviews

After reading Pinker’s book, I did some googling and read some reviews. Given the title of the book, I guess we shouldn’t be surprised that reason.com liked it! Other reviews were mixed, with The Economist’s “Steven Pinker’s new defence of reason is impassioned but flawed” catching the general attitude that he had some things to say but had bitten off more than he could chew.

The New York Times review argues that Pinker gets things wrong in the details (for example, Pinker pointing to the irrationality of “half of Americans nearing retirement age who have saved nothing for retirement” without recognizing that “the median income for those non-saving households is $26,000, which isn’t enough money to pay for living expenses, let alone save for retirement”), while the Economist reviewer is OK with the details but is concerned about the big picture, reminding us that rationality can be deadly: “Rationality involves people knowing they are right. And from the French revolution on, being right has been used to justify appalling crimes. Mr Pinker would no doubt call the Terror a perversion of reason, just as Catholics brand the Inquisition a denial of God’s love. It didn’t always seem that way at the time.” Good point. This is an argument that Pinker should’ve addressed in his book: violence can come from purported rationality (for example, the Soviets) as well as from open irrationality (for example, the Nazis).

The published review whose perspective is closest to mine comes from Nick Romeo in the Washington Post, who characterizes the review as “a pragmatic dose of measured optimism, presenting rationality as a fragile but achievable ideal in personal and civic life,” offering “the welcome prospect of a return to sanity.” Like me, Romeo suggests that Pinker’s individualist argument could be improved by making more connections to politics (in his case, “the political economy of journalism — its funding structures, ownership concentration and increasing reliance on social media shares”). Ultimately, though, I think we have to judge a book by what it is, not what it is not. Pinker is a psychology professor so it makes sense that, when writing about rationality, he focuses on its psychological aspects.