I've argued before that scientific method is applicable to much more than the subjects of the traditional hard and soft sciences. At least some aspects of history, human geography, social policy and morality are susceptible to empirical research. If you doubt this I suggest you look at the way that Steven Pinker uses data to test Kant's theories in Better Angels of our Nature.
One of the approaches used by would-be theorists is to look for cycles in history. Hegel, Marx and Toynbee all did so with decidedly mixed results. Now Peter Turchin, professor of Ecology and Evolutionary Biology at the University of Connecticut, has joined their ranks. Turchin claims that societies show 2-300 year cycles and that just three factors - economic output per head, the balance of labour supply and demand and attitudes to wealth redistribution - are enough to explain social evolution. Indeed, he says that his equations exactly match real wage rates since 1930.
I don't know if Turchin is right but his predictions are quantitative and can be tested. That's science.