It is a kit of cognitive tools that can attain particular goals in particular worlds.To understand what rationality is, why it seems scarce, and why it matters, we must begin with the ground truths of rationality itself: the ways an intelligent agent ought to reason, given its goals and the world...

Or the normative model may itself be correct only in a particular environment, and people accurately sense that they are not in that one, so the model doesn’t apply. Or the model may be designed to bring about a certain goal, and, for better or worse, people are after a different one. Though exp...

They then make syllogistic deductions: Steenbok and duiker can be run down in the rainy season because the wet sand forces open their hooves and stiffens their joints; kudu and eland can be run down in the dry season because they tire easily in loose sand.

The San also engage in critical th...

Yet for all the deadly effectiveness of the San’s technology, they have survived in an unforgiving desert for more than a hundred thousand years without exterminating the animals they depend on. During a drought, they think ahead to what would happen if they killed the last plant or animal of its...

Why doesn’t rationality seem to matter anymore?

It can be fixed, Steven Pinker argues, and if we don’t our democracy and environment may be at stake.

Sometimes we can hold people to a higher standard. They can be taught to spot a deep problem across its superficial guises. They can be goaded into applying their best habits of thinking outside their comfort zones. And they can be inspired to set their sights higher than self-defeating or collec...

They serve as an aspiration for those who want to be rational, which should mean everyone. A major goal of this book is to explain the most widely applicable normative tools of reason.

Normative models also serve as benchmarks against which we can assess how human schlemiels do reason, the ...

Though the problems are daunting, solutions exist, and our species has the intellectual wherewithal to find them. Yet among our fiercest problems today is convincing people to accept the solutions when we do find them. How should we think of human rationality? The cognitive wherewithal to underst...

The San of the Kalahari Desert in southern Africa are one of the world’s oldest peoples, and their foraging lifestyle, maintained until recently, offers a glimpse of the ways in which humans spent most of their existence. Hunter-gatherers don’t just chuck spears at passing animals or help themsel...

The sapience of the San makes the puzzle of human rationality acute. Despite our ancient capacity for reason, today we are flooded with reminders of the fallacies and follies of our fellows. Three quarters of Americans believe in at least one phenomenon that defies the laws of science, including ...

In social media, fake news (such as Joe Biden Calls Trump Supporters “Dregs of Society” and Florida Man Arrested for Tranquilizing and Raping Alligators in the Everglades) is diffused farther and faster than the truth, and humans are more likely to spread it than bots.How, then, can we understand...

They reason their way from fragmentary data to remote conclusions with an intuitive grasp of logic, critical thinking, statistical reasoning, correlation and causation, and game theory.The San track fleeing animals from their hoofprints, effluvia, and other spoor. They distinguish dozens of speci...

Excerpted from “Rationality: Why It Seems Scarce and Why It Matters” by Steven Pinker, Johnstone Family Professor of Psychology.

Rationality ought to be the lodest...