Again, the uncertainty in the estimate pales into insignificance when we look at the overall trend. Over the 11,000 years separating Gobekli Tepe from the International Space Station, the scale of cooperation, when measured by the labor costs of the most impressive building project, went up by four orders of magnitude--from 300 to 3,000,000. This is a huge--indeed, an astronomic--increase. And, of course, it was paralleled by an equally enormous increase in the scale of human societies. ***