Last week I had the pleasure of meeting Peter Turchin* and Peter Richerson, among others. Many things were discussed, but one the conversation brought me back to the results of Peter Turchin’s paper from last year, War, space, and the evolution of Old World complex societies. If you haven’t checked out the paper the figure to the right shows the major result: a model with only a few simple parameters was incredibly good at fitting the genuine growth and evolution of complex societies over 3,000 years. More quantitatively about two thirds of the variation spatially in ‘imperial density’ can be accounted for by the spread and emergence of military technology and the ruggedness of the landscape. Of course there are many objections you could make, and when Peter Turchin presented the map to the audience many people brought up areas where the model didn’t seem to be predicting very well. But, the very obvious take-home is that somehow a model with only a few parameters ended up doing a reasonable job predicting the distribution of the rise of empire in agricultural societies, and that’s something. You can have all the verbal models you want, but all that leads to in most cases is more argument, as you don’t have transparent access to the internal logic of someone else’s mind.
A second broader issue that Turchin has promoted is the idea of inter-group competition driving the rise of ultrasociality. In other words, cooperative societies stocked with highly social and altruistic individuals simply eliminated earlier forms of social organization which relied more on individual self interest. He is keen to not allow the argument to reduce down to ‘group selection,’ but rather to focus on the abstraction of multi-level selection more generally. Conflict and warfare are obviously key drivers of this culturally Darwinian process. But I wonder where that leaves us at the end of history? Perhaps without an external threat imposing cohesion and inducing norms to regulate and punish selfish strategies anomie will reign?
* At least in person