"The Life of Reason: The Phases of Human Progress" by George Santayana is a five-volume philosophical work published between 1905 and 1906. This sweeping examination of human progress explores reason's role in common sense, society, religion, art, and science. Blending materialist philosophy with Aristotelian ethics, Santayana charts how humans naturally develop ideal ends. He advocates for natural aristocracy over democracy, champions love and family while lamenting industrialism's rise, and treats religion as "splendid error"—beautiful mythology that reveals profound truths about humanity. (This is an automatically generated summary.)