While on my trip I decided to tackle Joseph Tainter’s The Collapse of Complex Societies. I learned of this book from Thomas Homer-Dixon’s excellent The Upside of Down. Since we were once again headed to see some ruins, I thought this an appropriate time to approach this book, although in the case of the Incas, we can easily identify “Guns, Germs, and Steel” (and perhaps horses) as the proximate causes of collapse. But other cases, like the Maya, the Western Roman Empire, and Easter Island, are among those situations that do not provide easy explanations. Tainter reviews virtually all of the prevailing theories. He identifies the prevailing theory in popular thinking and among some historians (Toynbee, for instance) as “mystical” explanations, a poor choice of words to my mind. Toynbee, following a long pedigree, thinks in terms of biological analogies, with birth, youth, maturity, decline, and death the pattern for “civilizations” as well as individuals. This, Tainter argues, provides a false and rather misleading or unhelpful analogy. The other theory, of “decadence”, seems more literary and moral than causative. So what is Tainter’s alternative? Declining marginal returns on complexity (complexity being a term of art in this instance). In short, he bases his theory upon a fundamental economic law (if you will suffer the dubious term here). His analysis and application of his theory to the Western Roman Empire argues that it was not barbarians, Christians, or plagues that brought down Rome, but a limitation on the value of complexity. He applies a similar analysis to the Mayans and to the Chaco Canyon civilization in North America. If he’s right, and I think that he makes a very strong argument (but see Peter Turchin’s War and Peace and War for an excellent competing theory), it has to be taken quite seriously, and if he’s right, then we have to think very carefully about our current predicament. Can we innovate our way out of the inevitable decline of petroleum? Can we get out from under excessive demands for complexity?
I highly recommend this book, and I count it an excellent part of my Big History reading project.