This series of lectures were prepared by the author for delivery at Harvard University Law School, but he died before he had the opportunity to present them. They are an illuminating and thought-provoking exposition of the nature of law and legislation, expounding on the differences between the written and unwritten law. The entire field of human conduct is explored, starting with conduct and its regulation in primitive society. The exposition commences with the search for the answer to the question: What is law? It ventures into the areas of government and politics.