There is a view of life which conceives that where the crowd is, there also is the truth, and that in truth itself there is need of having the crowd on its side. There is another view of life which conceives that wherever there is a crowd there is untruth, so that (to consider for a moment the extreme case), even if every individual, each for himself in private, were to be in possession of the truth, yet in case they were all to get together in a crowd -- a crowd to which any sort of decisive significance is attributed, a voting, noisy, audible crowd -- untruth would at once be in evidence.
For a “crowd” is the untruth.
Søren Kierkegaard, “That Individual”
One of the symptoms of groupthink is the members’ persistence in conveying to each other the cliché and oversimplified images of political enemies embodied in long-standing ideological stereotypes…
When a group of people who respect each other’s opinions arrive at a unanimous view, each member is likely to feel that the belief must be true. This reliance on consensual validation tends to replace individual critical thinking and reality-testing.
Irving Janis, Groupthink: Psychological Studies of Policy Decisions and Fiascoes, Second edition
I have always hated mobs. Thus I dislike mass demonstrations with their slogans and banners, marches and sit-ins, and all the rest of the obnoxious apparatus of modern protest. Usually the cause is bad, and the participants are ignorant yahoos. But I dislike such rallies even when the cause is good and the participants well-meaning. They may sometimes be necessary, but they are always regrettable and to be avoided if possible.