In a prior post, I noted the developments in American legal education over the last 150 years that have led to the central place of economics, psychology, and history, among other disciplines, to the study of law. One discipline I did not say much about, however, was my own: philosophy. And yet the philosophical study of law has been central to legal education in both the European and Anglophone traditions, and for a much longer time than the other important disciplines that now loom so large.

My own institution, the University of Chicago, invented in the 1960s and 1970s the economic analysis of law that has taken over legal education in the last generation, yet in its very first year as a law school more than a century ago, "Jurisprudence" (the philosophy of law) was one of the dozen or so courses offered to the very first student. Indeed, Chicago was the first law school to appoint a PhD philosopher, without a law degree, to its faculty, back in the 1930s! Why would that be?

The explanation has partly to do with the nature of philosophy as a discipline and partly to do with the deep affinities between law and philosophy.

Law is, first and foremost, a discursive discipline: lawyers and judges live in the domain of reasons and meanings. We interpret statutes and cases, articulate rules to guide behavior, and then argue about their import in particular cases. Judges write opinions, in which they give reasons for their conclusions. Lawyers offer arguments to persuade judges. Even lawyers who never argue cases in court still deal continuously with rules, their meanings and entailments.

Philosophy is, of course, the discursive discipline par excellence. The English philosopher John Campbell (who now teaches at Berkeley) famously and quite perceptively described philosophy as "thinking in slow motion." Lawyering, especially in an oral argument before an appellate court, is often "thinking in fast motion," but the key fact is that both disciplines are concerned with rational and logical thought. Lawyering typically demands more attention to rhetoric than has philosophy, at least since the time of the Sophists in the 5th-century B.C.. But the pejorative connotation of "sophistry" that has come down to us from Plato's successful defamation of the Sophistic philosophers should not mislead us: there is an art to persuasion, and that art is only partly exhausted by the rules of formal and informal logic. As the U.S. Supreme Court put it in Old Chief v. U.S. (1997), "A syllogism is not a story, and a naked proposition in a courtroom may be no match for the robust evidence that would be used to prove it."

Even allowing for that very real difference between legal and philosophical argument, the affinity is clear enough, so much so that American legal education takes its most famous pedagogical approach ("the Socratic method") from philosophy. Law teachers question students, much as Socrates questioned citizens of Athens about the nature of knowledge and justice. The method is supposed to illustrate and teach the kind of dialectical skill that lawyering, as a discursive discipline, requires.

It is equally important, however, that philosophy as a discipline concerns itself with literally everything, whether science or art or morality or law. We can always ask of any of these domains of human activity, "What is its nature? What makes it what it is?" Philosophers have asked this about science, about art and also about law. This is why "Jurisprudence" -- philosophical theorizing about the nature of law and legal reasoning, and the differences between law and morality -- has been a staple of the curriculum wherever law is taught at the university level. Indeed, it is a required subject for all law students at Oxford, as it is for most law students in Europe and South America. (Law is an undergraduate subject in almost all these jurisdictions, unlike in the U.S.)

As with many areas of philosophical inquiry, philosophical inquiry into law simply brings to light and makes explicit what is often implicit and unargued. We have all heard someone criticize a Supreme Court decision as "politically motivated, rather than following the law." But that already presupposes we know where the boundaries of law and politics are located, precisely what jurisprudential inquiry tries to illuminate! So, too, when commentators criticize a judge's reasoning in support of her conclusion, they invariably presuppose claims about the nature of law, legal interpretation and the character of legal reasoning. It is the task of jurisprudence to brings those presuppositions out in the open and subject them to scrutiny.

Philosophical inquiry has also played an important role in the development of the law. The two greatest legal philosophers of the past hundred years, the Austrian Hans Kelsen and the Englishman H.L.A. Hart, both had profound impacts on the law. Kelsen's jurisprudential work informed his influential contributions to the development of international law, including the creation of a "Constitutional Court" charged with judicial review of legislation for its constitutionality, a model adopted throughout the civil law countries of the world. Hart, through his influential extension of John Stuart Mill's utilitarian philosophy, was the driving intellectual force behind the decriminalization of homosexuality in Britain in the 1960s.

Within the academy, the influence of philosophers on legal scholarship has been substantial. When the "Chicago School" of economic analysis of law took over the legal academy starting in the 1970s, it was philosophers like the late Ronald Dworkin and my Chicago colleague Martha Nussbaum who articulated an alternative to "wealth maximization" as the goal of legal regulation. Some of my own philosophical work has vindicated the jurisprudential insights of the American Legal Realists--whose profound impact on American law and legal education I discussed previously--by offering a philosophical reconstruction of their position and defending it against critics like Hart. In twenty years of teaching jurisprudence, including American Legal Realism, I have been struck by how many students find it to be one of the most "practical" of courses, not because it taught them legal rules, but because it helped them understand legal reasoning and how judges decide cases, as well as bringing out into the open the implicit jurisprudential premises of both jurists and scholars.

David Hills, a philosopher at Stanford, famously said that philosophy is "the ungainly attempt to tackle questions that come naturally to children, using methods that come naturally to lawyers." Children typically do not wonder what the difference is between legal and moral obligation, or between justification and excuse in criminal law, but lawyers and law students do! And here the methods of philosophers -- so familiar to lawyers -- do come quite naturally, and will no doubt continue to do so wherever law is taught.