Not much to this post, just, again, harping on groupthink and mixing it in with a quote from Less Wrong:
The respected leader speaks, and there comes a chorus of pure agreement: if there are any who harbor inward doubts, they keep them to themselves. So all the individual members of the audience see this atmosphere of pure agreement, and they feel more confident in the ideas presented—even if they, personally, harbored inward doubts, why, everyone else seems to agree with it.
(“Pluralistic ignorance” is the standard label for this.)
If anyone is still unpersuaded after that, they leave the group (or in some places, are executed)—and the remainder are more in agreement, and reinforce each other with less interference.
(I call that “evaporative cooling of groups“.)
The ideas themselves, not just the leader, generate unbounded enthusiasm and praise. The halo effect is that perceptions of all positive qualities correlate—e.g. telling subjects about the benefits of a food preservative made them judge it as lower-risk, even though the quantities were logically uncorrelated. This can create a positive feedback effect that makes an idea seem better and better and better, especially if criticism is perceived as traitorous or sinful.
(Which I term the “affective death spiral“.)
It’s a bit distressing that it wasn’t religion that first came to mind when I read this, but (atheist) P. Z. Myers’ blog; I was one of the ones who “evaporated”.
So this isn’t just a problem with religion. It’s a problem with nationalism, football teams, favorite bands, race, sex/gender, alma mater, or any other grouping that humans put themselves into and identify with. If criticism is seen as sinful, then you know you’re dealing with an affective death spiral. Again, a phenomenon not restricted to religion.
A group composed of rationalists would (should?) never devolve into an affective death spiral, and thus would be less efficient than group of non-rationalists.