THINKING 101, Lesson 3: Ad Populum

Ad populum is a "fallacy," an error in logic or reasoning. It's also called "group-think" and "the herd mentality." People do it all the time because it's one of the easiest ways to prove their loyalties to a group or society.

It goes like this: if an idea is believed to be true (or false) by most people, then it MUST be true (or false).

Popular belief sometimes has a relationship with reality, and sometimes doesn't. When most people believe something, that doesn't prove it's true or false. It simply shows that the belief has a purpose in the group or society.

In choosing actions, "monkey see, monkey do" is a powerful motivation, and we can learn many things by copying others. But we should always remember that doing so may not lead to the wisest course of action.

It is also a fallacy to think that popular belief is always wrong. That's no smarter than thinking that the group is always right.