Having studied early childhood psychology for my thesis, it appears to me — especially considering things along the lines of Judith Lewis Herman’s views — that belief is related to survival. Thus a child who has an abusive parent at a very early age will grow up splitting their identity, with one part of their psyche knowing the parent is actually abusive, and the other part of the psyche having faith in a loving parent who is capable of bringing them up to full adulthood. Obviously this false belief is engendered by a survival mechanism, that is designed to protect the child from shock, for it would surely succumb to overwhelming psychological pressures and die if it did not dissociate from some of the reality.
So belief is linked to survival in human beings, and when there is a pathological influence during the developmental years, the child grows up with a tendency towards lying to themselves and others (ie. creating false beliefs), since he has learned to associate them with a sense of reassurance and, indeed, survival. That is the nature of a personality disorder that springs from early childhood experiences. The adult, who has survived these horrible circumstances of early childhood, does not seem to understand that they are lying. They feel that whatever they do or say is just “surviving”. Far from it being the case that the narcissist fears those that have power over him, the narcissists very source of lying comes about because he needs to have faith in those how have power over him. He learns to lie in order to protect an unsullied (but unrealistic) image of them that he holds in his head. Nonetheless, he has to maintain this image solely on the basis of “faith”, and so is in constant danger of losing his faith. When that happens, he will attack the image that he had held so dear, and proclaim that it was betraying him.
But the narcissist only gives us an extreme example of the general psychological connection between belief and survival. We are all inclined to believe whatever will spare us from shock — for we are shocked very easily when confronting our vulnerability. The disbelief in global warming, or in the vicious nature of The Patriarchy, and so on, is all very predictable, because these are actually shocking horrors. Paradoxically enough, our immediate survival (ie. not dying from shock) depends on our not believing in them. (Of course, our long term survival works on the exact opposite principle — requiring us to take these things very seriously, as if they were actually real!)