“Important on several levels—biographical, historical, and jurisprudential—Karl N. Llewellyn’s The Theory of Rules will immediately claim a place in the corpus of American legal theory.  Llewellyn’s prose here is less precious and idiosyncratic than in many of his other writings, and the remaining mysteries are dispelled by Frederick Schauer’s marvelously lucid introduction and detailed notes. As to several of the core problems of legal theory—the nature of rules, the differences between rules and standards, the roles of literalism and purpose in legal interpretation, the prediction theory of law—Llewellyn and Schauer have jointly produced an indispensable text.”

Adrian Vermeule | Harvard Law School

“With Frederick Schauer’s recovery and annotation of Karl Llewellyn’s unpublished manuscript, The Theory of Rules, an important statement of the jurisprudential perspective of one of the leading American Realist scholars is made available. Llewellyn’s contributions are enhanced and made accessible by Schauer’s valuable introduction and notes. The result is a fortunate interaction of the work of one of the great figures in American jurisprudence with that of one of the nation’s leading contemporary scholars.”

G. Edward White | University of Virginia School of Law

“Karl Llewellyn was one of the most creative and significant theorists of American law in the twentieth century, along with jurists and scholars like Benjamin Cardozo, Lon Fuller, and Richard Posner. The recovery of his never-before-published manuscript of The Theory of Rules is an important contribution to the intellectual history of twentieth-century legal thought. Frederick Schauer has done exemplary editorial work on the volume, both by supplying the missing scholarly apparatus the text required and through his substantial introduction, which expertly and lucidly surveys the main themes of The Theory of Rules, and locates them in terms of their jurisprudential significance today.”

Brian Leiter | University of Chicago Law School