Adam Smith began his public intellectual career with lectures in Edinburgh before becoming professor of logic at Glasgow in 1751 and professor of moral philosophy the following year. His teaching covered ethics, jurisprudence, political economy, and related subjects. The Theory of Moral Sentiments, published in 1759, explained moral judgment through sympathy, social observation, and the imagined impartial spectator. It established his reputation before the economic work for which he later became most famous.

From 1764 Smith traveled as tutor to the Duke of Buccleuch, meeting leading thinkers in France and Switzerland. The contacts widened his understanding of economic debate and allowed time for writing. Returning to Scotland, he worked for years on An Inquiry into the Nature and Causes of the Wealth of Nations, published in 1776. The book examined the division of labor, exchange, capital accumulation, public revenue, and the institutional conditions affecting national prosperity.

Smith criticized mercantilist restrictions and monopolies and argued that competition could coordinate economic activity without detailed central direction. He also recognized public responsibilities for defense, justice, infrastructure, and education and warned about the influence of merchants pursuing their own advantages. His account was not a blanket endorsement of every business interest or an argument that human behavior consisted only of selfishness.

In 1778 Smith became a commissioner of customs for Scotland, combining practical public administration with continuing revision of his books. He maintained friendships and correspondence with figures of the Scottish Enlightenment and revised The Theory of Moral Sentiments substantially before his death in 1790. At his request, much unfinished manuscript material was destroyed, limiting what can be reconstructed about some planned projects. His career created an influential framework for examining economic systems in relation to law, morality, and historical development. Later political traditions have claimed him in different ways, often extracting short phrases from a much broader argument. A balanced understanding considers his criticism of privilege and collusion, his concern with workers and education, and his account of social judgment as well as his support for commercial liberty. These features made his work foundational to political economy without reducing it to a single policy slogan.