This book investigates the historical transition in American legal thought from a reliance on natural law to the adoption of legal positivism. Stuart Banner, a professor of law, examines how the intellectual framework of the American legal system shifted during the nineteenth century. By analyzing judicial opinions, legal treatises, and public discourse, he argues that the decline of natural law was not a sudden event but a gradual process driven by changing social and economic conditions.

Legal scholars and historians recognize this work as a significant contribution to the understanding of American legal development. Readers frequently note the academic density of the prose, which provides a rigorous examination of the intellectual history of the American legal system.