At the heart of democracy lies a deep-rooted sense of optimism: the trust in people to govern themselves. A scientific foundation for this intuition is the theory of the Wisdom of the Crowd: if a lot of people (the more the better) make an independent guess, the average of their answers is likely to be close to the truth. With this method, sunken and undetectable submarines have been found. Moreover, research has shown that in a quiz show, asking the audience can give you the right answer more than 90% of the time.
Read these three articles to get a sense of some of the different ways in which crowd wisdom manifests: