The Wisdom of Crowds and Its Limits
When collective decision-making outperforms individual experts — and when it fails spectacularly. The science behind crowds, mobs, and democratic competence.
When Crowds Are Wise
In 1906, Francis Galton attended a county fair where 787 people guessed the weight of an ox. The average of all guesses was 1,197 pounds — just one pound off the actual weight of 1,198. No individual guess was as accurate as the crowd's collective average. James Surowiecki's influential 2004 book 'The Wisdom of Crowds' argued that groups outperform individuals under specific conditions: diversity of opinion, independence of judgment, decentralization, and a mechanism for aggregating individual views.
This has direct implications for direct democracy. If citizens' individual judgments are independent and diverse, the majority vote will tend to produce good outcomes — even if no individual voter is an expert. The Condorcet Jury Theorem formalizes this: if each voter is more likely than not to choose the correct answer, the probability that the majority is correct approaches 100% as the number of voters increases.