Democracy needs ignorant people, says science

You might think that democracies work best when people care and know about the key issues. But a new study argues that for a democracy to function at all, you need lots of ignorant people blindly siding with the majority.

That's the argument put forward by Princeton researcher Iain Couzin and his team, who make the argument that a fully informed electorate would collapse into an unworkable hodgepodge of minority factions or risk being dominated by a single forceful minority group. But if most voters don't really think about the issues, they will just tend to side with whoever is popular, allowing majority rule to continue and democracy to keep functioning. Yeah, you might want to check your last shreds of political idealism at the door for this one.

Couzin and his team argue for what we might call a sweet spot of ignorance. There needs to be just enough people who know anything about the issues to act as leaders for everyone else, but the majority disintegrates if there are too many viewpoints pulling in different directions. And while that seems to pretty aptly describe the last decade (at least) of American political discourse, I'd feel better if I knew just how the researchers arrived at their conclusions.

Why, by studying the behavior of fish, of course. Specifically, they looked at golden shiners, a species that is naturally attracted to the color yellow. The researchers took a bunch of these fish and trained most of them to act against instinct and swim towards a blue target, while the rest were trained to follow their natural preference and go for a yellow target.

When the researchers placed just these two groups together, the smaller group of yellow-seeking fish was able to dominate the blue-seeking fish, making them all swim to the yellow target 80% of the time. This is because their natural instinct gave them a stronger desire go after the yellow target than their counterparts. But then, when fish with no prior conditioning were added to the mix, the influence of the yellow-seeking fish quickly dropped away, and the initial, blue-seeking majority regained control. Couzin describes the strange role these uninformed fish play:

"Adding those individuals dramatically changes the outcome of group decision-making. They inhibit the minority and support the majority view, and this allows the majority to be heard and that view to dominate. We thought, ‘Wow, that's kind of interesting,' because you don't normally think that adding uninformed individuals to decision-making processes would have that sort of democratizing effect."

The next question, of course, is whether this phenomenon applies to humans as well. While we can't say for certain, Couzin and his team found that the phenomenon does hold up in computer simulations of typical human behavior. In the simulations, there is a similar threshold where adding in uninformed people can swing the general sentiment from a passionate minority to a less engaged majority view. The researchers want to further investigate this by performing experiments with human volunteers.

There is, however, a limit to this phenomenon. Couzin found that if you have twenty uninformed people and only one or two with strong opinions, there's too much noise and the whole process breaks down. And, of course, all this really shows is that uninformed people are necessary for the smooth operation of majority rule - and while the will of the majority is a part of a working democracy, there are plenty of situations where the more passionate minority actually has the best idea.

Science via Miller-McCune.