When I saw that Pinker was publishing an entire book on rationality, I was eager to find out what he had to say. Just last year I posted an extensive review of Enlightenment Now on Goodreads that can be found here in which I focus largely on Pinker's account of rationality. Given that there was only one chapter on rationality in Enlightenment Now I figured an entire book on the topic would reveal a more extensively and thoroughly developed theory.

If you're looking for an account of reason or rationality as such, however, you might not find it in Rationality, at least not easily. Instead, the bulk of Rationality consists of seven chapters on different methods of applying rationality. Each offers a brief overview or introduction to the topic at hand and they are written in Pinker's customary style – replete with phrases such as ‘jibber-jabber,’ ‘cock a snook,’ and ‘boo-boos’. If, however, you open Rationality expecting to find a definition or comprehensive account, you might find yourself in the same position Socrates found himself in when he asked Meno to define virtue. "How fortunate I am, Meno!" Socrates said, "when I ask you for one virtue, you present me with a swarm of them," (Meno, 72a). In a similar way, Pinker offers many different examples of rationality and, at times, seems to hold to a conglomerate theory of rationality: “rationality is not a power than an agent either has or doesn’t have, like Superman’s X-ray vision,” he writes. “It is a kit of cognitive tools that can attain particular goals in particular worlds” (6-7). Yet, if rationality is just the use of different tools in different situations, what is it that ultimately tells us whether to use a particular tool in a particular situation? While the seven areas of rationality Pinker reviews are important, he acknowledges they need to be used with an understanding of their limits. For example, formal logic, while important, needs to be abandoned in particular situations (94-101). Similarly, Pinker states that Bayesian reasoning also has its limits: there are times when we need to intentionally engage in ‘base-rate neglect’ – i.e. when dealing with particular demographic categories, such as sex, race, and religion (163). But, given these limitations, what is it that enables us to see beyond these tools? If rationality is just the use of various tools, it would not be able to identify the limitations of these tools. The carpenter operates beyond the use of any particular tool and, in so operating, is able to see in advance what tool is appropriate for what task. In a similar way, I suspect that human rationality is independent of the various ways it manifests itself. The question, however, is, if rationality really is beyond any particular tool or its use, what is it?

One theory Pinker alludes to without unconditionally endorsing is that of Hugo Mercier and Dan Sperber (who seem to have lifted it without credit from Gregg Henriques). According to them, human reason is an evolved ability to persuade others and to justify our own positions (87). Rationality, on their view, has more to do with survival than with accurately representing the world. However, if rationality is merely a survival mechanism fit for getting what we desire, are we to understand this theory as, somehow, having broken away from evolutionary impulses and truthfully described the itself?

It is not essential that we resolve this problem because Pinker offers several other definitions of rationality that he finds insightful. Early on, he suggests that rationality might be “ ‘the ability to use knowledge to attain goals’” (36). He then states that knowledge is typically “justified true belief” and suggests that an important aspect of rationality is the ability for us to get what we want. This, he claims following William James, is what distinguishes the rationality of Romeo from the non-rationality of magnet filings (37). Romeo reflects on the options available for being with Juliet and then pursues the path that most easily brings them together. In this way, Romeo uses reason to obtain what he wants. To act rationality, then, is to evaluate the possibilities and select the one that maximizes the chance of obtaining what you desire.

This definition of practical reason, however, is tempered on two sides. First, there is the moral injunction Pinker briefly but emphatically endorses, that we must act in a way that does not recognize a clear distinction between ourselves and others: “[t]he pronouns I, me, and mine have no logical heft – they flip with each turn in a conversation. And so any argument that privileges my well-being over yours or his or hers, all else being equal, is irrational” (68). This places a strong limit on the prior account of practical reason as pursuing the best path to achieve one’s goals. Now, in light of this restriction, we must pursue the best path that does not unevenly infringe on the interests of others.

Practical reason is also tempered by theoretical reason. while practical reason is about achieving our goals, theoretical reason is about knowing what is true. This definition of theoretical reason is, on Pinker’s view, more or less self-evident. When people debate or challenge each other, they invariably demand reasons from their interlocutors. These reasons are then analyzed in terms of whether they are true or whether they contribute to determining the truth of the conclusion being debated: “As long as people are arguing and persuading and then evaluating and accepting or rejecting the arguments,” Pinker writes, “it’s too late to ask about the value of reason. They’re already reasoning, and have tacitly accepted its value” (39).

These two views of reason and rationality – the practical and the theoretical – are fairly widespread. In short, practical reason is about getting what you want, within limits, while theoretical reason is about determining what is true. In an ideal world, the two will work together. When determining the best course of action, I should try to discern what is true about the world – knowing the best course of action depends upon knowing the truth about the various ways to achieve it. Similarly, we discover the truth most easily when we follow the best path. If truth is our ultimate goal, then practical reason will help us pursue it.

The problem, however, is that practical and theoretical reason are not always aligned. Pinker points this out indirectly when he identifies the taboo against using various demographic base-rates when predicting behaviour. But there are many other areas where tension between practical and theoretical reason arise: there are situations where the use of human beings as disposable test subjects might lead to more knowledge and there are conceivable scenarios where circulating falsehoods can help bring about a more harmonious society. The question, given these definitions of theoretical and practical reason, is less whether they are true, but whether the universe is structured such that they are able to coherently function together. In this context, Pinker’s invocation of the Henriques / Mercier and Sperber thesis is interesting insofar as it throws a wrench into this more traditional account. If we accept rationality as a mere product of evolution, as a tool evolved to assist us in our survival, then it seems a bit of a leap to suppose that it is also geared towards generating truths. After all, from Socrates to Jesus to Martin Luther King Jr., knowing and sharing the truth has not been conductive to survival.

Given these tensions, the task set for Pinker is to show why his accounts of practical and theoretical reason can work together. That is, he needs to show that the pursuit of our goals, within moral limits, is typically aligned with the pursuit of truth. This is what Pinker tries to show in the final two chapters of the book.

In chapter ten, Pinker offers a diagnosis of what is going wrong in contemporary society. Why is it that so many otherwise healthy individuals find QAnon appealing? Why do they resist vaccines? Here, Pinker’s conclusions draw from a range of psychological studies, now fairly well known, that identify a persistent ‘myside’ bias in our reasoning. The cost of changing our beliefs given a limited supply of evidence is often considered too great and so we reinterpret this evidence in light of our prior convictions (292-298). In the final chapter, Pinker offers evidence for the view that increased rationality is aligned with moral and social progress (328-340). Here, he quotes pre-Enlightenment, Enlightenment, and post-Enlightenment thinkers to show that Enlightenment thought has produced good arguments for, among other causes, gender, racial, and sexual equality, and religious tolerance.

Returning to chapter ten, in an effort to bolster his own view of the world, Pinker draws from Hugo Mercier and Joseph Henrich to identify a distinction between ‘reality-based beliefs’ and ‘mythological beliefs.’ The former, he states, are about “physical objects around them, the other people they deal with face to face, the memory of their interactions, and the rules and norms that regulate their lives” (299-300). By ‘reality,’ Pinker means, drawing from Philip K. Dick, “that which, when you stop believing in it, doesn’t go away” (298). The other, mythological, realm concerns “the world beyond immediate experience: the distant past, the unknowable future, faraway peoples and places, remote corridors of power, the microscopic, the cosmic, the counterfactual, the metaphysical” (300). In a very odd endorsement of a kind of ‘logical positivism,’ Pinker claims that “[w]e children of the Enlightenment embrace the radical creed of universal realism: we hold that all our beliefs should fall within the reality mindset” (301).

There are several problems with this distinction. First, shortly after establishing that we need to move all our beliefs into the reality-domain, Pinker identifies four key principles of science. One holds that “all physical interactions are governed by a few fundamental forces” while another states that “the mind is the information-processing activity of the brain” (306). Not only is it not true that all scientists throughout history have accepted these principles or that one needs to accept all of them to carry out science, it’s not clear whether all they are even open to testing. Pinker presents them as fundamental axioms and not as evidence-based conclusions. This is fine, but it doesn’t blend well with his earlier aim to ensure that all our beliefs are testable. The problem encountered here is not unlike the fundamental problem besetting logical positivism, i.e., is the claim that there ought only to be observation sentences and analytic truths itself either an observation sentence or an analytic truth?

Further, Pinker’s treatment of religious and conspiratorial belief is patronizing at best. He cites Mercier’s claim that these beliefs are not supposed to be true or false by referring to the fact that hardly anyone acted on the Pizzagate conspiracy and Christians today do not generally try to convert others by force: “they don’t take the next logical step,” he writes, “and try to convert people to Christianity at swordpoint for their own good, or torture heretics who might lure others into damnation” (299, 301-302). But this is a very strange conclusion given that non-violence is one of the central tenets of Christianity (Matthew 5: 38-47; 26:52). Further, isn’t one of the original and main features of Christian conversion that it has to occur voluntarily? That Jesus’ followers were sent out to persuade others of the gospel by relating their testimonies, by healings, and by explaining the scriptures? Further, even as figures like Charlemagne were trying to forcibly convert barbarians, others like Alcuin of York tried to convince them that Christianity cannot spread through violence and coercion. Pinker’s use of these examples to establish his conclusion about mythological beliefs is, I find, quite strange. It is also challenged by the fact that people do act on these beliefs. They acted on them when they stormed the Capitol, and they continue to act on them when they reject vaccines and refuse to wear masks. How, then, are we to reconcile the idea that mythological beliefs are not supposed to be true or false with the evidence that people actually hold these beliefs to be either true or false? Further, how do we reconcile this with the observation that some of Pinker’s own beliefs transcend the ‘true/false’ dichotomy? How, for example, is Pinker supposed to respond to the view that all human beings are equal? Or the idea that money, political institutions, and goals do cease to exist once we stop believing in them? The arguments Pinker lists in chapter eleven in favour of equality are grounded on inconsistencies in the audience’s views: Americans simultaneously held all people to be equal while owning slaves; absolute sovereignty is rejected while still upheld in the family, etc. But if we ask what the evidence is that all human beings are inherently equal, it’s difficult to find an answer. If we appeal to intelligence, genetic traits, capacities, or even rationality (on the view of rationality endorsed by Pinker), not all people are equal. So equality is something we must presuppose and it is not the consequence of any physical trait.

In all, then, it appears that Pinker’s reality/mythology distinction is easily undermined. And this is to avoid dealing with Pinker’s puzzling claim that he doesn’t “believe in anything you have to believe in” (325).

Given the ultimate difficulties inherent in Pinker’s view of reason, where does this land us? I find myself partial to Immanuel Kant’s account of theoretical reason (The Critique of Pure Reason, A298/B355 – A338/B396). On Kant’s view, everyone is rational and rationality is non-normative. We are rational insofar as we try to find some kind of unity. Conspiracies, on this view, are just as much products of reason as science is. Metaphysical systems are just as rationally generated as ideas about nature. The task of Kant’s first critique is to reign in the excesses of reason. It has ventured too far, he argues in the preface, away from empirical data (Avii-Aix).

Given this view of reason, irrationality can be understood as operating “within the house of reason,” as Donald Davidson puts it (“Paradoxes of Irrationality"). It is the failure to allow that one’s views might be false or to admit the possibility that the world is other than how one sees it. Hence, an irrational person is also rational. If we apply this theory to conspiracies, we see that the irrationality of these theorists rests in their failure to allow for the possibility of being wrong.

Given this rationality/irrationality distinction, it is worth reflecting on Pinker’s own convictions. One element in particular comes to light – that of alien visitations. In several spots, Pinker refers to alien visitations as clearly irrational. He remarks with amazement that “a quarter to a third of Americans believe we have been visited by extraterrestrials” (286). Now, I don’t know what Pinker would consider an ‘alien visitation.’ However, it seems reasonable to me to think that if the recent UAP (“unidentified aerial phenomena”) videos are of genuine alien spacecraft, whether there are aliens in them or not, it is safe to conclude that aliens have visited earth in the same way our rovers on Mars license supposed Martians to believe humans have visited Mars. Given these terminological preliminaries, whatever you think about the recent American intelligence report, it would at least seem warranted to be open to the possibility that they signal an alien visitation. And yet, as Leslie Kean astutely notes in “How the Pentagon Started Taking U.F.O.s Serious,” “[i]f [the skeptic] Mick [West] were really interested in this stuff, he wouldn’t debunk every single video . . . . He would admit that at least some of them are genuinely weird.” Just as those who seem to ‘know’ that the objects in a new certified UAP video are alien spacecraft are considered irrational insofar as they leave no room for doubt, those who, upon seeing the same video, ‘immediately know’ the objects are not alien spacecraft are also irrational. Both the resolute believers and the resolute skeptics consistently seem to know in advance what the truth is. The problem for both is just a matter of making the evidence fit their prior conclusions.

It is this kind of irrationality – the irrationality of resolute denial – that Pinker is susceptible to. Instead of presenting himself as working firmly to be in the side of ‘reality,’ however confused that domain is, Pinker should, instead, acknowledge that there are many things he is uncertain about. He should be free to admit, for example, that he is unsure whether aliens have visited earth, whether miracles can occur, whether God exists, and so on. Yet, as Avi Loeb has noted, academia is very unforgiving towards those who posit hypotheses that are outside what’s deemed acceptable. Whether Loeb’s convictions about ‘Oumuamua turn out to be true or false, he has correctly identified a certain irrationality within the academy, an irrationality that correlates with knowing in advance what kinds of conclusions are possible, what kinds of phenomena cannot exist, and what kinds of explanations are acceptable. Pinker has provided us with the resources for a more robust understanding of belief, one that is not strictly governed by bivalence, but in the final chapters of Rationality retreats to clichés about the rational scientist and reality.

Overall, the opening and central chapters offer good introductions to various kinds of reasoning. My main issue is that Pinker does not think about what brings all these tools together. Perhaps the tensions that exist between the urban and the rural, the working-class and academia would relax if each side adopted a bit more humility.