The Big Questions series is designed to let renowned experts confront the 20 most fundamental and frequently asked questions of a major branch of science or philosophy. Each 3000-word essay simply and concisely examines a question that has eternally perplexed enquiring minds, and provides answers from history's great thinkers. This ambitious project is a unique distillation of humanity's best ideas. In Big Questions: Philosophy, bestselling author Simon Blackburn addresses 20 essential questions.