Turchin believes that history can indeed be a science, with laws as inexorable as the law of gravity. He claims to have found the general mechanisms that cause empires to wax and wane - laws as true today as they were during the Roman or Ottoman Empires. According to this view, the world order is in a state of perpetual change and the global powers today will inevitably be replaced in the coming centuries.
For example, Turchin argues that the fluctuations in population of pre-industrial societies can be linked to periods of political instability and civil war. His theory shows how population growth caused by increased prosperity can itself trigger such social instability, thus sowing the seeds of its own decline. This, says Turchin, is how civilisations and empires collapse.
Fascinating stuff, if only for giving a new statistical gloss to some old ideas of cyclic or mechanical history, but I suspect cliodynamics will remain a reductionist oddity, much like the other areas of 'social physics' explored by Ball in his book Critical Mass. Still, it's nice to see that in this new article, Ball finally gives credit to that notable fictional precedent for the field, the psychohistory of Asimov's Foundation novels.