Adam Smith (1723-1790) was a Scottish professor, economist, and philosopher and a key figure of the Scottish Enlightenment. Smith wrote two major works, The Theory of Moral Sentiments and An Inquiry into the Nature and Causes of the Wealth of Nations. The latter, often abbreviated as The Wealth of Nations, is the first theoretical work of economics. Smith laid the foundations of classical free market economic theory. He developed the concept of division of labour and theorized that rational self-interest and competition leads to economic prosperity.