Grünbaum claims it is possible that all belief in God is a delusion, meaning a false belief which is engendered by irrational psychological motives. I dispute this on the grounds that in many cases belief in God is engendered by purely cultural factors, and this is incompatible with its being engendered by psychological ones. Grünbaum also claims that saying a culturally engendered belief cannot be a delusion makes social consensus the sole arbiter of reality. I dispute this on the grounds that we can say that socially engendered beliefs fail to be delusions because they fail to meet the psychological criterion, rather than because they are true.