Modern capitalism ignores this truth as it operates under the illusion that earth has inexhaustible resources and an unlimited capacity to absorb waste.

A human society is an ecosystem. Like any other ecosystem, it depends for its existence on flows of energy, and as with any other ecosystem, the upper limit on its complexity depends ultimately on the difference in concentration between the energy that enters it and the background into which its waste heat disperses. (This last point is a corollary of White’s Law, one of the fundamental principles of human ecology, which holds that a society’s economic development is directly proportional to its consumption of energy per capita.) Until the beginning of the industrial revolution, that upper limit was not much higher than the upper limit of complexity in other ecosystems, since human ecosystems drew most of their energy from the same source as nonhuman ones: sunlight falling on green plants. As human societies figured out how to tap other flows of solar energy—wind power to drive windmills and send ships coursing over the seas, water power to turn mills, and so on—that upper limit crept higher, but not dramatically so.   The discoveries that made it possible to turn fossil fuels into mechanical energy transformed that equation completely. The geological processes that stockpiled half a billion years of sunlight into coal, oil, and natural gas boosted the concentration of the energy inputs available to industrial societies by an almost unimaginable factor, without warming the ambient temperature of the planet more than a few degrees, and the huge differentials in energy concentration that resulted drove an equally unimaginable increase in complexity. Choose any measure of complexity you wish—number of discrete occupational categories, average number of human beings involved in the production, distribution, and consumption of any given good or service, or what have you—and in the wake of the industrial revolution, it soared right off the charts. Thermodynamically, that’s exactly what you’d expect.   The difference in energy concentration between input and output, it bears repeating, defines the upper limit of complexity. Other variables determine whether or not the system in question will achieve that upper limit. In the ecosystems we call human societies, knowledge is one of those other variables. If you have a highly concentrated energy source and don’t yet know how to use it efficiently, your society isn’t going to become as complex as it otherwise could. Over the three centuries of industrialization, as a result, the production of useful knowledge was a winning strategy, since it allowed industrial societies to rise steadily toward the upper limit of complexity defined by the concentration differential. The limit was never reached—the law of diminishing returns saw to that—and so, inevitably, industrial societies ended up believing that knowledge all by itself was capable of increasing the complexity of the human ecosystem. Since there’s no upper limit to knowledge, in turn, that belief system drove what Catton called the cornucopian myth, the delusion that there would always be enough resources if only the stock of knowledge increased quickly enough.