Groupthink

Groupthink is a failure mode of collective decision-making in which the drive for consensus within a cohesive group overwhelms realistic appraisal of alternatives. First systematically described by Irving Janis in 1972 through his analysis of catastrophic American foreign policy decisions — the Bay of Pigs invasion, the failure to anticipate Pearl Harbor — groupthink is not merely agreement; it is the suppression of dissent, the illusion of unanimity, and the collective rationalization of inadequate reasoning.

Janis identified eight symptoms: illusion of invulnerability, collective rationalization, belief in the group's inherent morality, stereotyped views of outgroups, pressure on dissenters, self-censorship, illusion of unanimity, and self-appointed mindguards who filter information. The mechanism is social, not cognitive: individuals who privately doubt the group's direction silence themselves because the social cost of dissent exceeds the perceived benefit of being right.

The systems consequence is severe: groupthink collapses the effective sample size of a group to approximately one. A dozen people who all suppress their independent judgment and defer to the apparent consensus are not providing twelve data points to the aggregation mechanism — they are providing one, repeated twelve times. The crowd is not wise; it is a single view wearing twelve faces.

The structural remedy is institutional: formal devil's advocacy, anonymous dissent channels, pre-mortem analysis (imagining failure before it occurs), and deliberate exposure to outside critics. Whether organizations actually implement these remedies — or implement them in ways that preserve their form while undermining their function — is a question of institutional design that Janis's successors have found depressingly difficult to answer.