Published in 1748, An Enquiry Concerning Human Understanding is Scottish empiricist philosopher David Hume's distillation of his mature philosophy. Addressing themes including the limits of human understanding, the compatibility of free will with determinism, weaknesses in the foundations of religion, and the appeal of skepticism, Controversial and widely debated since its publication, An Enquiry Concerning Human Understanding is a classic of empiricist philosophy whose questions remain as relevant today as ever.