Notions of gods arise in all human societies, from all powerful and all-knowing deities to simple forest spirits. A recent method of examining religious thought and behaviour links their ubiquity and the similarity of our beliefs to the ways in which human mental processes were adapted for survival in prehistoric times.
It rests on a couple of observations about human psychology. First, when an event happens, we tend to assume that a living thing caused it. In other words, we assume agency behind that event. If you think of the sorts of events that might have happened in prehistoric times, it’s easy to see why a bias towards agency would be useful. A rustling of a bush or the snapping of a twig could be due to wind. But far better to assume it’s a lion and run away.
The survivors who had this tendency to more readily ascribe agency to an event passed their genes down the generations, increasingly hard-wiring this way of making snap decisions into the brain. This is not something that people need to learn. It occurs quickly and automatically.
The second trait is about how we view others. While living together in a tribe would have had many advantages for survival in prehistoric times, getting along with everyone would not always have been easy. Comprehending others’ behaviour requires you to understand their thoughts and beliefs, especially where these may be incorrect due to someone not knowing the full facts of a situation.
This is known as “theory of mind”. This idea says that we automatically assume that there are reasons behind others’ behaviour which we try to work out in order to better understand why they behave the way they do. Not having this ability has been proposed to underlie developmental disorders such as autism.