The idea of God isn't a supernatural idea. If the idea of God were supernatural, then religion would be true. The idea of God, the idea, the representation of something supernatural is not itself supernatural. If it were, then we would be out of business. Precisely what we're trying to explain is, to quote the title of a book by Pascal Boyer, the “naturalness of religious ideas,” explain, in other terms, how these ideas of the supernatural can occur in the natural beings we are, in human brains and minds and culture, and have the kind of success that they have, in spite of the fact that you can't explain them in the way that you explain so many human ideas, such as ideas that are acquired through experience of the things they are about.
We humans have ideas about plants and animals because we experience plants and animals in a special way with the brain we have. We don't experience God, or goblins or witches, because there are no such things. Nevertheless, we have rich complex ideas about them, a richness in many ways comparable to the ideas we have about plants, animals and the natural things around them.
How is that possible? The issue is what makes these kind of ideas psychologically, cognitively attractive — "catching", such that they stay with you in your head and you may want to communicate them and to guide your behavior on their basis. And also: which of them, among all the unrealistic unsupported ideas that are possible in infinite variety, are going to be so "catching" as to achieve cultural success, in the manner of the many religious ideas that has been around for centuries?
It's not like any blatantly false idea will somehow make it to a cultural success — far from it. Most of them don't stand a chance. What's special about ideas of the supernatural? I argued long ago that it had to do with the fact that they are rooted in our cognitive dispositions, in the way we approach the natural world. Instead of departing from our commonsense ideas so to speak at random, they're like direct provocation — they have always an aspect of going directly against what should be the most intuitively obvious.
So for instance it's part of our common sense knowledge of living forms, that an animal can’t be both a dog and a cat, but the supernatural is full of creatures like dragons that typically belong to several species simultaneously. It's part of our common sense knowledge of the physical world that an entity cannot be in two places simultaneously, but ubiquity is a distinctive trait of supernatural beings. It's kind of again commonsense, in our commonsense psychology which we deploy in everyday interaction with one another, that one's visual perceptions are limited to what's present in front of one's eyes. Supernatural beings typically can see the past, the future, and things on the other side of earth. So supernatural beings are kind of provocations to commonsense. They are really deeply counterintuitive. That's an idea I suggested a long time ago and that Pascal Boyer has developed and enriched in a remarkable fashion, and which I think is one of the cognitive ingredients that helps explain the success of religious ideas. Of course, it's only one little fragment of a kind of complex picture.
Like most anthropologists, Sperber does not "believe in" religion. What he knows, though, is that religion is found in all cultures, at all times. It's panhuman.
What this suggests is, we need religion as much as we need food, water, love and sex. It suggests we all "have" religion. Even ardent atheists. Even serial killers. Even mass murderers. We might not recognize their deities, but they're there, nevertheless.