Extrapolating on the Wisdom of Crowds theory, new research suggests that small crowds might be wiser than large ones. Perhaps. But what if it’s a tight-knit community of morons? Would the thinking be good then? What if it’s a politicized group that makes decisions that have immediate benefits for its own members without regard to others or to long-term ramifications? What if we’re talking about a doomsday cult? From Drake Bennett at Businessweek:

“The wisdom of crowds is one of those perfectly of-our-moment ideas. The phrase comes from New Yorker writer James Surowiecki, whose book of that title was published almost a decade ago. Its thesis is nicely summed up in its opening, which describes the 19th-century English scientist Francis Galton’s realization, while attending a county fair, that in a competition to guess the weight of an ox the average of all of the guesses people had submitted (787 in all) was almost exactly right: 1,197 pounds vs. the actual weight of 1,198 pounds, a degree of accuracy that no individual could attain on his own. As individuals we may be ignorant and short-sighted, but together we’re wise.

The implication is that the bigger the crowd, the greater the accuracy. It’s like running an experiment: All else being equal, the larger the sample size, the more trustworthy the result. The idea has a particular resonance at a time when online businesses from Amazon.com to Yelp rely on aggregated user reviews, and social networks such as Facebook sell ads that rely in part on showing you how many of your friends ‘like’ something.

A new paper by the Princeton evolutionary biologist Iain Couzin and his student Albert Kao, however, suggests that bigger isn’t necessarily better. In fact, small crowds may actually be the smartest. ‘We do not find the classic view of the wisdom of crowds in most environments,’ says Couzin of their results. ‘Instead, what we find is that there’s a small optimal group size of eight to 12 individuals that tends to optimize decisions.’

The research started from the fact that, in nature—where, unlike at county fairs, accuracy has life-or-death consequences—many animals live in relatively small groups. Why, Couzin wondered, would so many species fail to take advantage of the informational benefits of the crowd?”