Hugo Mercier opens Not Born Yesterday with a claim that runs against a long current in Western thought. Humans did not evolve as credulous dupes. We evolved as wary judges of what we hear. Mercier calls the faculty open vigilance. We depend on what others tell us, and that dependence creates an opening for liars. Selection answered the threat. It built filters that weigh the source, test the argument, check the claim against what we already know, and track who has burned us before. The result is an animal that trusts, but trusts on conditions.
Mercier and his teacher Dan Sperber (b. 1942) reached this position through a longer argument about reason. If communication paid liars more than it paid honest speakers, language would collapse, because no listener could afford to believe anyone. Language survives. So listeners must hold defenses that keep deception unprofitable most of the time. Reason, on their account, serves this social task. It produces arguments to persuade others and scrutinizes the arguments others bring. Solitary truth seeking is not its first job. The biases that look like flaws in a logic seminar, confirmation bias above all, work as features in a room full of people trying to talk one another into things.
The thesis sounds modest. Its consequences are not. A large share of modern academic and professional life rests on the opposite premise. Misinformation studies, media effects research, propaganda scholarship, much of political consulting, and the fact checking industry all assume that the public is easy to fool and needs rescue. Mercier argues that mass persuasion almost always fails, that propaganda rarely moves minds, and that people who hold beliefs elites dislike usually hold them for reasons, not because someone hypnotized them. That argument carries a cost for anyone who makes it. This essay names the thinkers who make it and weighs what they pay.
Mercier stands at the center, and his price is quiet rather than loud. Cognitive scientists respect his work. Yet he sits at the edge of the public conversation about disinformation, because his findings cut the rationale out from under the interventions that conversation exists to justify. If the public is hard to manipulate, then alarm about a misinformation crisis loses much of its force, and so does the case for censorship and expert curation. His book gets read as a qualification, a caveat to bolt onto the standard story, rather than as a challenge to the story itself. Citing Mercier costs nothing. Building on him costs funding lines and committee seats, so few build on him in the places where the money sits.
Sperber pays a stranger price, the price of being foundational and half forgotten at once. The theory of open vigilance grew from his work with collaborators. His reach runs across anthropology, linguistics, cognitive science, and the study of how beliefs spread. He is less famous than thinkers whose models flatter the listener less, who picture the mass of men as suggestible and in need of guidance. The market for ideas about human nature rewards drama. A theory that says people defend themselves well draws less attention than a theory that says people fold under pressure.
Pascal Boyer (b. 1951) extends the argument into the territory where the gullibility story seems strongest, the spread of strange belief. Conspiracy theories, rumors, and superstitions look at first like proof that people swallow anything. Boyer turns that reading over. Such beliefs spread because they engage systems built for other tasks, threat detection and coalition tracking among them. A rumor that an enemy group plots harm catches because it pulls a lever the mind already holds, not because the listener has lost the power to doubt. The belief earns its grip by fitting a prior suspicion, not by defeating vigilance. Boyer takes fire from those who want religion and rumor explained as simple error, and from those who want them explained as pure domination. He offers a third route, and a third route wins few allies in a fight with two sides.
Paul Bloom (b. 1964) presses against the wider claim that feeling drowns judgment. Bloom argues that moral and social judgment leans hard on deliberate reasoning, and that the campaigns built to sway the public miss far more than they hit. He blurbed Mercier’s book and shares its skeptical cast toward tidy psychological tales. Bloom has made a career of telling audiences the unwelcome thing, that empathy misleads, that suffering does not ennoble, and the welcome thing about human competence sits inside that habit. His standing protects him. The argument still annoys colleagues who want a darker picture of the ordinary mind.
Leda Cosmides (b. 1957) and John Tooby (1952–2023) laid groundwork the whole program stands on. They argued that the mind holds specialized routines shaped for particular problems, among them a sharp sense for cheaters in social exchange. A creature with a cheater detector is not a creature you fool with ease. Their field, evolutionary psychology, carries a heavy tax in parts of the academy, dismissed as a factory of just so stories or treated as suspect on political grounds. The tax falls on the whole enterprise, and the vigilance thesis inherits a share of it by association.
Joseph Henrich (b. 1968) arrives at a kindred conclusion from the side of culture rather than the side of the individual mind. Henrich argues that human success rests on social learning, on the slow pile up of useful knowledge across generations, stored in custom and craft. The striking fact about people is not that they copy blindly. It is that they copy well. They track who holds skill, who earns deference, who gets results, and they aim their imitation at those targets. Prestige and reputation guide the search. Henrich draws fire from two quarters. Psychologists who center the lone mind think he hands culture too much. Critical theorists dislike the suggestion that an old custom might carry hard won wisdom rather than mere mystification and control.
Steven Pinker (b. 1954) belongs in the company as an ally more than as a theorist of vigilance. His project runs against the portrait of man as a helpless object of conditioning. He stresses competence, problem solving, and the slow widening of reason across history. He praised Not Born Yesterday without reserve. For this and for the rest of his work he has become a chosen villain of several academic factions, a target of protests and attempts to bar him from platforms, because he refuses the story of the public as victim of ideology and false consciousness. His prominence shields him from the obscurity that swallows quieter dissenters. It also makes him a larger target.
Three further names sit near the program without sitting inside it, and honesty asks that the distinction stay visible. Thomas Sowell (b. 1930) is no evolutionary psychologist, yet his life’s work assumes that ordinary men hold local knowledge and practical sense. In his telling the masses are rarely the fools. The intellectuals are, because they trade the concrete for the abstract while plain people answer to incentives and facts on the ground. James C. Scott (1936–2024) studied peasants who saw power for what it was, bent to it when bending paid, and kept their own counsel underneath. His hidden transcripts are the record of people who were never deceived, only careful. Nassim Nicholas Taleb (b. 1960) argues that experts mistake book knowledge for the practical kind and so underrate the filters that ordinary practice has built over centuries. Each of these men reaches a conclusion that rhymes with Mercier’s. None of them got there through the science of cognition, and a reader who folds them into the research program without a caveat blurs a real line. Their inclusion shows how wide the convergence runs. It does not show that the convergence is a single school.
Why does the price exist at all. The answer points back to the trades that turn the gullibility premise into a salary. A profession that claims to diagnose hidden distortion, false consciousness, ideological capture, manipulation, unconscious bias, draws its authority from the size of the affliction it treats. The more gullible the public, the greater the call for experts who can lift the public out of error. Mercier’s picture shrinks the affliction and with it the standing of the healer. It also bears on a body of famous experiments. Social psychology built much of its reputation on laboratory work that seemed to show men caving to the group and to authority, the conformity studies of Solomon Asch (1907–1996) and the obedience studies of Stanley Milgram (1933–1984). To call those results artificial, or read too broadly, is to pick a fight with an establishment that has a stake in the finding.
Here the argument touches the work of Stephen Turner (b. 1951). Turner’s long quarrel with essentialism in social science and Mercier’s quarrel with the gullibility premise strike at the same institutional habit, the habit of locating a hidden defect in ordinary people that only the credentialed can name and cure. Strip the defect away and the question changes shape. The old question asks who manipulated these people into their wrong beliefs. The new question asks why these people trust sources that the questioner does not trust. The second question is harder. It grants the other side reasons. It trades the comfort of diagnosis for the discomfort of disagreement, and it offers the asker no flattering role as physician to a sick public.
Mercier does not claim that people reason well or arrive at truth. He claims something less comforting. People are often good at sensing when someone tries to work them, and they decline to trust the same authorities the intellectual class trusts. Their resistance is not a failure of cognition. It is cognition doing its evolved job, aimed at targets the diagnostician would rather it spared. That is the finding the misinformation economy cannot easily absorb, and that is why the men and women who publish it pay in the coin of marginal standing while their critics keep the budgets.
