In the case of religions, standard individual belief in reality is replaced by a communally held falsehood which serves to hold the 'believers' in a socially cohesive group. In fact, the falsity of the belief serves to identify the members of the group and cement them into a stable unit capable of independent action. The more you hammer on your age of the earth, the more firmly they hold to the goofy 'truth' of 6000 years age of the earth. The social glue it provides holds more firmly if the belief is false. Were they to believe in what could be rationally supported, then anyone could join.
Don't fall for the 'truth will ultimately prevail' fable, often it doesn't.
Don't fall for the 'truth will ultimately prevail' fable, often it doesn't.
So how, exactly, does God know that She's NOT a brain in a vat? 
