The key argument of this book is that laws and customs are not sufficient in themselves to enable large groups of humans to live together effectively in community. Nation states and empires which worshipped “Big Gods” had strong evolutionary advantages compared to those that depended on small local or natural gods. This is because “Big Gods” outside the Earth would be constantly watching everything people did; because of this the fear of “hell” or divine punishment was a powerful force ensuring “good” behaviour.
Norenzayan sets out 8 principles which support his argument:
1. Watched people are nice people
2. Religion is more in the situation than in the person
3. Hell is stronger than heaven
4. You can trust people who trust God
5. In religions actions speak louder than words
6. Unworshipped gods are impotent gods
7. Big Gods are needed for big groups
8. Religious groups co-operate in order to compete.
Despite the rise of the secular consumer world, most of the world's population are still extremely religious. The dominant religions of today are those that evolutionary forces have selected from the thousands of outlier religions which have arisen over the centuries. New religions are constantly being invented – perhaps 2 or 3 each day. In a research study of 200 19th century utopian groups Richard Sosis found that a very strong pattern emerged. The average lifespan of religious groups was 25 years – in 80 years 9 out of 10 had disappeared. For secular groups the lifespan was much shorter – a mere 6.4 years and 9 our of 10 had disappeared in 20 years.
AN says that humans are the only species which has been able to live together in large groups where individuals show sustained cooperative behaviour towards strangers. This has only happened in the last 12000 years since settled agriculture appeared. Prior to the existence of police forces it was Big Gods that enabled these behaviours to work effectively.