What is law? This question has preoccupied philosophers from Plato to Thomas Hobbes to H. L. A. Hart, yet many others find it perplexing, even frivolous. Why do we need a general theory of what law is? What does it have to do with legal practice? In Legality, Scott Shapiro draws on current work in the theory of action to offer an original and compelling answer to this perennial philosophical question. Breaking with a long tradition in jurisprudence, Shapiro argues that legal systems are not defined by rules but by plans. He shows how thinking about laws as plans resolves many vexing puzzles about the nature of law and demonstrates its profound implications for the practice of legal interpretation.By introducing us to the Planning Theory, Shapiro not only develops a highly distinctive and promising answer to the question of what law is, but also vindicates the value of the question itself.

Through careful argumentation and analysis of current legal controversies, Shapiro shows that jurisprudence is not formal and arid, as some have alleged, but vitally important. In fact, many of the most pressing issues that confront lawyers demand that these grand philosophical questions be resolved first. Written in clear, jargon-free language, and presupposing no legal or philosophical background, Legality offers a ground-breaking new theory of law as well as an excellent introduction to, and defense of, classical jurisprudence.