Adam Smith considered his first major book, The Theory of Moral Sentiments, his most important work. Indeed, the tome was a wild success upon its publication, selling out immediately. It has not lost popularity since. In this legendary work, Smith discusses the nature of morality, and the motives behind and origins of these “sentiments.” This work provides the philosophical underpinnings for his later works, as well as elucidating the psychological and moral foundations of the workings of a complex society. Smith parses many important concepts in this book, with the central questions perhaps being: Where do our moral principles come from? Are they divine and inborn, reflection of man-made laws, or rational, based on their usefulness to society? Smith’s answers to these questions and more, and his explanation of how such sentiments, however derived, influence society’s self-coordination, have interested lay and scholar alike for hundreds of years.