Joseph Tainter

American archaeologist whose The Collapse of Complex Societies (1988) provides the leading theoretical account of why complex societies collapse — through the diminishing returns on complexity.

The diminishing returns theory of collapse: Tainter argues that complex societies (Roman Empire, Maya, Chaco Canyon) collapse not primarily due to external shocks, climate, or invasion but because complexity itself has diminishing marginal returns. Each additional layer of administration, military infrastructure, or bureaucracy initially solves problems but eventually costs more than it produces. When the cost-benefit ratio of complexity goes negative and the population can no longer sustain it, the 'solution' is simplification — collapse. Influential across archaeology, political science, and systems thinking.