The Greek discovery of practical reason, as the skilled performance of strategic thinking in public and private affairs, was an intellectual breakthrough that remains both a feature of and a bug in our modern world. Countering arguments that rational choice-making is a contingent product of modernity, 'The Greeks and the Rational' traces the long history of theorising rationality back to ancient Greece. In this book, Josiah Ober explores how ancient Greek sophists, historians, and philosophers developed sophisticated and systematic ideas about practical reason. At the same time, they recognised its limits - that not every decision can be reduced to mechanistic calculations of optimal outcomes. Ober finds contemporary echoes of this tradition in the application of game theory to political science, economics, and business management.