I think many of those systems were created by elites who dominated the use of violence and fed off the work of the subordinate classes. Their use of violence wa

I think many of those systems were created by elites who dominated the use of violence and fed off the work of the subordinate classes. Their use of violence was a skill that was crucial for them to learn to be good at but only had to be used intermittently, so they had a relatively large amount of free time to spend on governing and thinking. This explanation is only partial, of course.