In 1785, a French mathematician named Marie Jean Antoine Nicolas de Caritat (known as Marquis de Condorcet) used statistics to champion democracy.

Democracies are based on the collective decisions of large groups of people. But citizens aren’t experts on every topic, and so they may be prone to errors in the choices they make. And yet, Condorcet argued, it’s possible for a group of error-prone decision-makers to be surprisingly good at picking the best choice.

Condorcet’s logic was simple. Assume you have a group of people each independently making a choice about a question. Assume that they have a chance of making the wrong choice–but that their choices are better than random. If the decision they’re trying to make is either thumbs