The Wisdom of Crowds, According to Aristotle

Maybe you’ve heard of the “wisdom of the crowd” — the theory that the average of a group of people’s guesses, opinions, or inclinations is probably better than any particular guess, opinion, or inclination picked out of the group.


Aristotle seems to have been the guy who first pointed it out, and he did so in chapter ⅺ of book Ⅲ of the Politics, which I’ll be looking into today.

“[I]t is possible that the many, no one of whom taken singly is a sound man, may yet, taken all together, be better than the few, not individually but collectively,” he says. This is in part because in a large group of people, there are many sorts of expertise and virtue represented, even if no individual is universally expert or completely virtuous.

If true, Aristotle says, this is a point in favor of democracy or at least a broad distribution of political power.

One would think that many sorts of stupidity and vice are also well-represented in such a group, so for this theory to hold, expertise and virtue must be stronger or perhaps better-represented. Though Aristotle does not try to argue this point, it seems compatible with what he said about virtue and vice in The Nicomachean Ethics. In that book, he says that virtue is a narrow middle zone surrounded on both sides by broad regions of vice. So perhaps the mass of people who lack the virtue have vices that oppose each other and cancel out.

But it seems to me that there are examples of groups of people making decisions that are more stupid than the typical individual in the group would make on his or her own, so perhaps this theory is contingent on the type of group or the type of decision or the method by which the decision is arrived at or some other factor. Aristotle says that not “every people and every large number” exhibit the wisdom of crowds, and he isn’t prepared to believe brutes or animals have it (though I think it or something like it has since been observed in animals).

Aristotle goes so far as to say that “the many are better judges of works of music and poetry: some judge some parts, some others, but their collective pronouncement is a verdict upon all the parts,” which is a declaration of anti-snobbish support for popular art that I would not have expected from Aristotle, and which contrasts strongly with the highbrow / lowbrow distinction that is commonplace today and that trusts the judgment of the connoisseur much more than the best-seller lists.

He also notes in connection with this effect that there are uncanny ways in which mundane objects or features can, in combination, become profound or beautiful: artworks in which the arrangement of ordinary objects lends them beauty, or a handsome person whose features, considered individually, are not particularly handsome.

(Modern inventions like equity markets and prediction markets refine the wisdom of crowds ideas in interesting and potentially useful ways, and their validity and limits continue to be debated today.)

There is of course tension between this wisdom-of-crowds idea and Aristotle’s usual tendency to trust in the wisdom of a rare subset of particularly refined and virtuous men of the leisure class. He points out the possibility of a hybrid system that could include aspects of both, one that he attributes to Solon, the reformer of the Athenian constitution. In that system the office holders are respectable men of property, but the mass of citizens have an opportunity to “participate in deliberating and judging.”

This is appealing because while it is risky to let the mass of not-particularly-virtuous, unpropertied people take part in government (as they’ll likely misuse whatever power they have), it’s also risky to completely lock them out of power, as they’ll grow resentful and cause trouble. Aristotle returns here to his pragmatic concern for the stability of the state. He speculates that a hybrid system like this may be preferable to either a pure democracy or pure aristocracy.

But deliberating and judging on matters of statecraft is a tricky business, and it seems sensible at first glance to let experts take care of it. You wouldn’t ask your neighbors to vote on who should perform your surgery: you’d go to a surgeon who’d been trained by surgeons and certified by a board of surgeons.

But, Aristotle notes, there are some things in which experts are not necessarily the best judges. It’s the diner, not the chef, who gets the vote on whether the meal was satisfying; the residents, not the architect, on whether the house is well-designed; and so forth. Maybe statecraft is more like that. The experts are entitled to their expert opinion, but we all have to work with the system and all have an opinion worth respecting about how well it’s working.

The wisdom-of-crowds principle can allow the uncouth masses to participate in government without their individual lacks of good judgment having as bad an effect as they would if any one of them were granted an office of authority. In a manner of speaking, the mass of people may collectively have the virtues, even if most of them don’t have the full set. And the mass of people, when you add their middling wealth together, may qualify as a sort of aggregate aristocrat. So if you squint and look at them this way, perhaps it isn’t unreasonable to give them a seat at the aristocratic governing table as a unit.

I’m struck by how much of Aristotle’s system has been adopted by the modern liberal constitutional order. The mass of people have a sort of pathetic dilute political power: to vote for the officials who actually then wield political authority. But the people love this humble power and are willing to fight for it, and it makes them feel involved enough that they rarely threaten the constitutional order itself or the power of the elites over them. The actual officials overwhelmingly come from the propertied oligarchy. The mass indeed is full of political idiots who couldn’t be trusted to rule for the most part. What’s missing is any attention to the virtues among those in the oligarchy. They’re every bit as much of a mess there as the masses, and the wisdom of the crowds seems only wise enough to pick out the least virtuous among them.

Index to Aristotle’s Politics