The core theses of this book are straightforward:
1. Some societies face multiethnic frontiers, and they respond by developing higher levels of cooperation. You have to bind together to clear out and kill those Indians.
2. Eventually the result is empire.
3. Empires decay. They wallow in luxury and the preconditions behind their previously high levels of cooperation go away.
4. The ability to cooperate is the key variable in human history.
So argues Peter Turchin — a professor of ecology — in his recent War & Peace & War: The Life Cycles of Imperial Nations. Imagine Jared Diamond’s method extended into the formation of empires and the origins of war, with a dose of Hari Seldon, and you have this book.
In addition to the broader theses, Turchin takes on why Europe stayed disunited after the collapse of the Carolingian Empire (disunity was the default setting), why the eastern and western parts of the Roman Empire took such different courses (the Eastern Empire was largely a new creation), why the fall of the Roman Empire has earlier roots than you think (the frontier changed in nature), and why the Russians have been so obedient to tyrannical rulers (egalitarian structures, combined with a frontier). The author does not shy away from bold claims, nor does he give much attention to possible counterexamples; try his other books for further support but don’t expect your doubts to be resolved.
Some of the sentences scare me: "Cliodynamics predicts complex dynamical behavior for historical empires, with shorter cycles embedded within longer cycles, and so on [sic]."
If you judge a book by its vulnerability to criticism, this one makes for easy pickings. But Tolstoy wasn’t crazy, Ibn Khaldun is more important than you think, and Turchin will tell you why. Recommended, especially for those who like fearless and speculative minds.