The project of applying general systems theory to social sciences is crucial in today’s crisis when social and ecological systems clash. This book concretely demonstrates the necessity of a Marxist approach to this challenge, notably in asserting agency (struggle) as against determinism. It similarly shows how Marxism can be reinvigorated from a systems perspective. Drawing on his experience in both international systems and low-input agriculture, Biel explores the interaction of social and physical systems, using the conceptual tools of thermodynamics and information. He reveals the early twenty-first century as a period when capitalism starts parasitising on the chaos it itself creates, notably in the link between the two sides of imperialism: militarism (the ‘war on terror’) and speculative finance capital.