Economist, philosopher, civil servant, and politician, John Stuart Mill (1806-1873) made his mark as a liberal in Victorian society. His major works--System of Logic and Principles--as well as his famous essays--"On Liberty" and "Women"--reveal his extraordinary skill at clarifying difficult political and philosophical problems. Based on a detailed assessment of the influences on Mill's life, William Thomas traces the main ethical, economic, and psychological doctrines explored in his work and offers an unusual interpretation of the origins and development of Mill's philosophy.