Rationality and Progress

And God shall wipe away all tears from their eyes; and there shall be no more death, neither sorrow, nor crying, neither shall there be any more pain: for the former things are passed away. – John of Patmos, 21:4

Having reviewed Steven Pinker’s (2021) excellent volume on Rationality (Krueger, 2022a) and having replied to his question "What is wrong with people?" – his chapter 10 – in this space (Krueger, 2022b), it is time to turn to his concluding chapter, which raises the overarching question of whether rationality is good – for anything. The short answer is yes, it is, as Rationality as a Gesamtkunstwerk amply demonstrates.¹ The long answer is that Rationality could have ended with a bigger bang. As it stands, the concluding arguments commit some of the errors bemoaned in earlier chapters. Consider the issues of health, life, wealth, and ethics.

Health

Pinker argues that irrationality, and woo-woo beliefs, in particular, are bad news for the believer’s chances of survival. I felt the pain, remembering that my parents refused to give me antibiotics when I had the whooping cough. A will to live and a determined immune system got me through; the small white homeopathic pills my mother called – without irony – “biochemistry” did not help.

Pinker makes his case with anecdotes such as the above. He refers to a website that lists myriad anecdotes of woo-woo healing, from acupuncture to vitamin megadoses (and other weird beliefs), gone bad. Trying to make a general case with anecdotes is an informal fallacy and perhaps one of the worst. And it begs the question of rationality.

A stronger case would focus on the lack of evidence for homeopaths et alii manage to heal. Such a case could be done (and has been made), but it is not the point Pinker seeks to establish. His point is not that homeopathy is ineffective but that it is harmful. This is doubtful as homeopathy has no active ingredients whatever, so it can’t harm. The issue is rather that harm comes when woo-woo believers refuse to seek evidence-based treatment, and this is a different matter.

Life

Researchers have amassed a wealth of data showing that individuals capable and willing to think rationally garner more favorable life outcomes than their woo-woo brethren. Importantly, this association, though small, holds when general intelligence is statistically controlled. Pinker focuses on individual rationality throughout Rationality, but there is an ongoing subtext regarding collective rationality and social (and national) outcomes. At times, Pinker notes that the two can be at cross-purpose in the tragedy of the rationality commons. This is a complicated notion as it suggests that the irrationalists, who free-ride on the collective welfare, are, in fact, the rational ones in the game-theoretic sense (where defection is rational). The formal error here is a reverse ecological fallacy. If we cannot infer statistical associations over individuals from associations over groups or nations (the ecological fallacy), we can’t do the inverse either.

Wealth

Pinker is bullish on progress in the form of material wealth. “Progress,” he declares, “is shorthand for a set of pushbacks and victories wrung out from an unforgiving universe” (p. 325). Progress, in other words, is complexity or a reduction of entropy. He declares that “poverty needs no explanation; it is the natural state of humankind. What needs explanation is wealth” (p. 326). Wealth is the figure; poverty is the ground.

Surprisingly, Pinker musters no direct evidence at the national level, or the historical level that increases in rationality predict or cause increases in wealth (though there is evidence at the individual level; see above). Indeed, the San of the Kalahari, whom Pinker had praised early on in the book for their rationality so finely attuned to their environment, are relatively poor to Western eyes (although not to their own eyes; Suzman, 2017).

The unnoticed elephant in the room is wealth inequality within a society. No theory of rationality and progress is complete without taking a position on evaluating inequality or whether there is an optimal level thereof. It is critical in this context to distinguish between those who are poor in a rich society and those who have no material possessions when no one does, or no one desires them.

Ethics

Finally, Pinker argues that much moral progress has come from reasoned arguments against religious intolerance (Castellio), war (Erasmus), cruel punishment (Beccaria), homophobia, and cruelty to animals (Bentham). This is a strong case indeed, and the moralists may ask themselves where they think moral progress comes from if not from reasonable and humane reflection and persuasion.

Ethics and Morality Essential Reads

Do People Everywhere Cheat?

Maybe We Need to Say Less About Ethics

The issue is tricky, and Pinker himself notes that there is no clean way to ground morality in rationality (although there have been valiant efforts). But the goal is a worthy one. If reasoned argument and respect for rationality can make humanity more tolerant and less mean, much has been achieved.

Pinker as prophet

Rationality is a magisterial book that should be read with care and reflection. The author has been attacked by those who misconstrued his message as one of rosy-tinged optimism (hence the eschatological epigraph). This is a misconception. I recommend Steven Pinker’s response to Nassim Taleb’s claim that Pinker teleologically forecast a golden age. I too had flirted with the interpretation that Pinker had run aground a teleological fallacy when he wrote that the arc of history bends toward rationality. Perhaps it has been bending that way, but some irrationality will always be with us, a point Pinker concedes. It is part of our nature; the distribution of irrationality will always have a fat tail.