随群

if you want to know your weight, you can step onto a scale. if you want to know the dimensions of a room, you can measure them directly. but how can you establish the accuracy of your own political or social views or decide which hairstyle suits you best? there are no simple physical tests or measuring devices for answering these questions. yet we want to be correct about such matters, too. the solution to this dilemma is obvious: To answer such questions, we refer to other people. We use their opinions and actions as guides for our own. such reliance on others, in turn, is often a powerful source of the tendency to conform.

- extracted from textbook