Via Big Think:
Question: Is all religion madness?
Oliver Sacks: I think I need to say that there are specifically some conditions of the brain which predispose to mystical or religious thinking. In particular, when people have so-called temporal lobe epilepsy or temporal lobe seizures, they may have religious or mystical visions. Or even between seizures, they may have a gradual personality change which disposes them to mystical and religious thinking.
I think that thinking of this sort is, if you want, built into the nervous system. Although it doesn’t have to take an explicitly theistic notion.
[Albert] Einstein always used to say that the most beautiful thing in the world is the mysterious. And I think that the fundamental sets of mystery and awe and of the sublime is behind all science and art. Basically, I think, science springs from a sense of nature’s mysteriousness and the wonder of nature. And there is no need to invoke anything supernatural. Indeed, I think too much involvement in the supernatural may blind one to the wonder of nature. And I’m slightly terrified by certain fundamentalist who say, let the planet go to hell, the Final Coming is going to be soon. God will take care of it all.
I live, for myself, happily and completely within nature. I love it. I have a sense of being at home. I don’t pine for anything else. And so, I think, those parts of my temporal lobes are devoted to, as it were, to an almost religious feeling for nature.
For more on the temporal lobe seizures and religiosity see this bit from V.S. Ramachandran‘s documentary for the BBC called Phantoms in the Brain: