We usually think of intelligence as something that belongs to individuals. But some of the most interesting examples of problem-solving come from groups rather than single minds.

In 1906, scientist Francis Galton observed visitors at a livestock fair guessing the weight of an ox. Most guesses were inaccurate, but the average of hundreds of guesses came remarkably close to the actual weight. The observation became an early example of what is now called the wisdom of crowds.

The idea is simple: when people make independent estimates, their mistakes can sometimes cancel each other out. But independence is important. If everyone gets their information from the same incorrect source, a large crowd can simply produce a larger version of the same mistake.

This is why diversity matters more than size. A group becomes more useful when its members have different experiences, knowledge, and ways of approaching a problem.

The internet has made this principle much more powerful. Wikipedia, open-source software, and online question-and-answer communities all rely on distributed knowledge. No single contributor knows everything, but together, thousands of people can create something far more comprehensive than one person could.

Yet crowds can also become dangerously wrong. Social media shows how quickly opinions can spread because they are popular rather than because they are accurate. Once people begin copying one another, apparent agreement can replace independent thinking.

This reveals an important distinction: collective intelligence is not the same as consensus. A group does not become intelligent simply because everyone agrees. Sometimes disagreement is exactly what allows mistakes to be discovered.

The real strength of a crowd comes from combining different perspectives while still allowing those perspectives to be questioned.

Perhaps intelligence, then, is not always about finding the smartest person in the room. Sometimes it is about creating a room where different people can contribute, challenge assumptions, and correct one another.

A crowd becomes intelligent not when everyone thinks alike, but when everyone brings something different to the table.