The general term for this sort of thing is "social proof", and you see some amount of it in all cultures: http://en.wikipedia.org/wiki/Social_proof http://en.w

The general term for this sort of thing is "social proof", and you see some amount of it in all cultures: http://en.wikipedia.org/wiki/Social_proof http://en.wikipedia.org/wiki/Social_proof It's actually a pretty good heuristic most of the time -- hence its ubiquity -- but obviously it has a bunch of pathological corner cases, and it's open to exploitation by salesmen, politicians, cult leaders, and anybody else who does mind control for a living.