What Makes Group Decisions Go Wrong. And Right.
In the 1970s, psychologist Irving Janis pioneered research into a phenomenon that goes by a name most people know, probably understand intuitively, and perhaps have experienced personally. I’m talking about “groupthink.” Janis saw the symptoms of groupthink in a host of bad collective decisions he studied. He was particularly intrigued by White House fiascos, like the Bay of Pigs invasion and the escalation of the Vietnam War, but also detected groupthink in the Challenger space shuttle disaster. Janis called it “a deterioration in mental efficiency, reality testing and moral judgements as a result of group pressures.”1
But when, exactly, does groupthink take hold and ruin a committee’s, a governing body’s, or a society’s decision-making process? How little independent thinking does there have to be for collective deliberation to go astray? And what role does rethinking your opinions play? A recent paper, by Vicky Chuqiao Yang and colleagues, published in the Proceedings of the Academy of Sciences, investigates these very questions.2
Yang is an applied mathematician who studies collective
