Did your brain evolve in order to understand God?

A couple of weeks back there was an intriguing article in New Scientist on how religion came to be by the Evolutionary Psychologist Robin Dunbar. He started from the assumption that originally religion didn’t exist, so sometime in our past it came to be invented. His argument is that religion requires a complicated brain to make sense, so it was a relatively recent invention. It’s all to do with orders of intentionality.

Animals don’t have religion because they only have first order intentionality. They think purely from their own position. An exception are some great apes. Chimpanzees for example can deceive. They can pretend not to notice something they want, and so not draw other chimps’ attention to it, returning to retrieve the item when the area is quieter. If I think to leave the banana to you won’t know about it, that’s second order intentionality. It means that chimpanzees have a theory of mind and have more social behaviours than your average animal. Things get more interesting when you have three orders of intentionality. The example Dunbar uses is “I believe God wants me to act in a righteous manner.” I think that God thinks I should think about what I’m doing. Three steps and you have a capacity for personal religion.

Dunbar adds in your mind to create fourth order intentionality. In his words “I want you to believe that God wants us to act righteously.” This makes what he calls social religion possible. But he says that still doesn’t commit you anything, so a fifth order “I want you to know that we both believe that God wants us to act righteously,” is necessary for communal religion.

I think that confirms my sub-human status as I’m still having trouble following that. If I deconstruct that correctly then fourth-order intentionality is I know that you know that God knows what I’m thinking. That’s four steps and I’m happy with that. The fifth-order is I know that you know that we know that God knows what I’m thinking. Dunbar argues elsewhere that Shakespeare was doing well because he wrote in the fifth order and because that was his intention he must have been operating at sixth-order [Word Doc / HTML]. But that’s rare.

The effort in reaching these higher levels is difficult. The Social Brain Hypothesis [PDF / HTML] is that the brain had to develop the complexity to manipulate information in a social arms race. Except with more brains and fewer arms. This has advantages for the individual, but sophisticated thinkers also have an advantage as a group. Group intentionality as ordered by religion becomes possible and this may have been an advantage that archaic Homo Sapiens had over its contemporaries. He’s even got nice graphs to show it.

Graphs showing orders of intentionality in primates from New Scientist.

The graph on the left shows a linear correlation between the size of a primate’s frontal lobes in the brain and their achievable order of intentionality. The graph on the right shows (lets ignore Neanderthals for now) how increasing orders of intentionality came through evolution. Australopithecines, like apes, had second-order thought while Homo Erectus had third-order. It looks neat and I’m not convinced. Nearly every data point is interpolated rather than measured. The order of intentionality is directly proportional to measurements of cranial capacity. If the correlation is proven then that’s sound, but all we have are the three data points on the left graph to support this. What the right graph really tells us is that cranial capacity has tended to increase in species of Homo over time and that’s not huge news. It’s also a problem when we do think about Neanderthals.

Neanderthal brains were on average around 10% bigger than modern humans. That would place them slightly above us on the graph and the sheer spread of Neanderthal points compared to the one for modern humans is a bit misleading. It would suggest that Neanderthals were capable of deeper thinking than us, and that’s a difficulty because we don’t know if – or to what degree – Neanderthals were capable of symbolic thought. I have a suspicion that, like modern humans, they were capable of symbolic but like contemporary Homo sapiens they didn’t have much symbolic thought. A lot of symbolism, like cave paintings or figurines, doesn’t date till after the Neanderthals are gone. It could be that Neanderthals were victims of a Great Leap Forward in archaic humans, but it’s not certain. However much I’m willing to credit to Neanderthals, I couldn’t seriously argue they were more sophisticated thinkers than Homo sapiens. The flints found at sites are also an indicator of a degree of brain power and while they were good, they weren’t Homo sapiens. So I’m far from convinced that the linear correlation holds for Neanderthals and, if that’s the case, why should it also hold for other hominids? This objection has implications for the timing of how complex thought arose, but I don’t think it undermines his central thesis, that religion is a result of increasing complexity in the mind brought on to deal with societal stresses.

It’s an explanation that has spooky poetic qualities if you want to get mystical. The idea of being given a land to conquer by the will of the Gods is common in ancient texts, and perhaps easier if the people you’re killing don’t have the mental capacity to have Gods. If you want to follow Catholic doctrine you could argue that this was when God chose to ensoul a species. If you prefer an atheistic view you could take the view that the Neanderthals were the first victims of religion.

His recent book The Human Story expands on this in more detail and it’s been available surprisingly cheaply recently from Amazon’s marketplace thing and Abebooks. —–