From Shapiro, Scott J., Legality, Harvard University Press (2013):
[M]ost legal academics and practitioners find the question “What is law?” distinctly unmoving. Unlike philosophers, they simply don’t see the point of worrying or speculating about the nature of law and frequently dismiss such questions as formal and arid, far too scholastic to be of any real interest or value. Richard Posner captured this sentiment well in his Clarendon Lectures: “I have nothing against philosophical speculation. But one would like it to have some pay-off; something ought to turn on the answer to the question ‘What is law?’ if the question is to be worth asking by people who could use their time in other socially valuable ways. Nothing does turn on it.”
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Complaints about the “irrelevance” of jurisprudence are of course neither new nor surprising. In 1879 the great British constitutional scholar A. V. Dicey proclaimed that “[j]urisprudence is a word that stinks in the nostrils of a practicing barrister.” Lawyers are pragmatic both by temperament and necessity—their job, after all, is to help their clients, and if they repeatedly fail in this regard, their livelihood is at risk. Why should lawyers care about a discipline that studies their practice without telling them anything that will affect how they engage in it? Those who study, teach, and write about tort law can arguably be said to contribute to the practice of tort law. But those who inquire into the nature of law seem to have no discernible effect on the practice of law of any kind. What, then, is the point of jurisprudence? To many members of the bar, and legions of law students, the answer is by no means obvious.
My aim in what follows is to show that, contrary to these venerable jurists, a great deal does turn on the question of “What is Law?” In fact, I will argue that it is not possible to address many of the most pressing practical matters that concern lawyers—including who has the legal authority to regulate which conduct and how to interpret legal texts—without addressing the analytical questions that have traditionally preoccupied philosophers of law as well. One of the main goals of this book will thus be to show that analytical jurisprudence has profound practical implications for the practice of law—or, in other words, that the answer to what the law is in any particular case depends crucially on the answer to what law is in general.
