The intelligence of the creature known as a crowd, is the square root of the number of people in it.

In the quote, "The intelligence of the creature known as a crowd, is the square root of the number of people in it," Terry Pratchett is humorously commenting on the collective intelligence of a group. The phrase suggests that, as the size of a crowd increases, the overall intelligence of the group doesn't grow at the same rate. Instead, it grows at a diminished pace, represented by the square root function. This implies that larger crowds often lack the clear, rational thought that smaller, more cohesive groups might have.

Pratchett's use of the mathematical concept of the square root serves as a clever metaphor for how collective decision-making can sometimes become diluted or chaotic. While individual members of a crowd might be highly intelligent, their combined wisdom can become muddled when they are grouped together. This highlights how crowd behavior can often lead to irrational outcomes, as each individual’s input becomes less effective as the group size grows.

The quote originates from Terry Pratchett's satirical and often witty take on human nature, particularly as seen in his famous Discworld series. Pratchett had a unique ability to blend humor with insightful observations about society, and this quote reflects his playful yet critical view of group dynamics.

Ultimately, Pratchett is underscoring a concept that has been explored by social scientists: that larger groups can sometimes be less intelligent or effective than smaller, more focused ones. It's a commentary on the potential flaws of crowd behavior and a reminder that the wisdom of many isn’t always greater than that of the few.