There's a perverse research experiment that goes something like this.
A room contains a researcher and a small stool. Hanging over the stool is a banana on a string. The researcher wears a white lab-coat and holds a fully pressurized fire-hose. An arbitrary number of monkeys is released into the room.
Sooner or later one of them will make for the stool to try and grab the banana. Yet as soon as that monkey climbs the stool and approaches his prize, the researcher lets him have it with the hose. And not only does that monkey get it, but all monkeys in the room (whether they touched the banana or not) get sprayed. After soaking them roughly for a few moments, the researcher turns off the hose.
Perhaps another monkey gets brave or hungry. When he climbs the stool and touches the banana, the researcher lets him have it. And as before, all the monkeys also get doused, whether they moved towards the banana or not. Repeat this process enough and, after the group has suffered enough soakings, the following effect should be noticed: Should any monkey make for the stool, the rest can be counted on to beat him silly before he reaches either it or the banana, sparing themselves. After awhile, the group avoids the banana even as their bellies growl.
Now say the researcher removes a monkey and brings in a new one to replace him. No big surprise, one of his first actions might be to make directly for the banana. And of course the others won't allow this, for if he should make it they all get sprayed again. They administer a beating to the confused newcomer, until he learns not to near the stool.
Should the experiment continue, perhaps after replacing every monkey in the original generation, one can even remove the researcher. The descendants enforce the social order even though they may never been sprayed or even know about the researcher. By now no monkeys have directly experienced the hose, and in fact no white-coated danger exists, yet still their options are self-curtailed. There is no risk in the banana. Yet they avoid it, none quite certain why.
Well I said it was a perverse experiment. To draw conclusions about human behavior after studying monkeys may be irrational. Is that saying the effects may not be present as tides of social pressure adjust our path? Maybe the human advantage is to regularly examine our preconceptions, our reasons for doing things, or proscribing them.