WHAT, in general, is a good reason for decision by a court of law? This is the question of jurisprudence; it has been asked in an amazing number of forms, of which the classic What is Law? is only the briefest. I propose to consider, in this Comment, one recent answer to this question that supplied by Professor Richard Wasserstrom in his book, The Judicial Decision. I do so because Professor Wasserstrom's argument shares with much other recent jurisprudence some dubious and generally unrecognized assumptions about the logic of legal justification. My principal purpose is to expose these assumptions. Wasserstrom's book is distinguished from the bulk of the American literature of legal philosophy by its care and clarity. He writes with full control over his organization and so enables us to study his argument with some confidence that we understand what he is trying to prove and why. This is in refreshing contrast to other recent efforts along the same line much of American jurisprudence has consisted in nothing more rigorous than the translation of homilies into rhetoric, and back again. Wasserstrom's careful articulation of his purposes, and of the assumptions he intends to make, are indispensable aids in identifying and assessing the hidden more powerful assumptions which his argument also involves. Wasserstrom approaches the question, What is a good reason for a judicial decision, by attempting to construct the model of an ideal decisive procedure. His search for this ideal is conducted through a sort of tournament. Three principal candidates are introduced. The first two are the procedures of precedent (it prescribes that all particular cases are to be decided by an appeal to the relevant, extant legal rule, i.e., to precedent)2 and the procedure of equity (it insists that individual cases be decided by appealing to that which is just or equitable for the particular case).3 The third is Wasserstrom's own two-level procedure, modeled on the ethical doctrine of restricted utilitarianism. It counsels the judge faced with decision to proceed as follows. He must determine which of the rules of law that he might select to give in the situation, considered as a rule and not simply with respect to its present application, best promotes the function of the legal system. (It is assumed that each legal system ought to have such a function.) In making this determination, he must take *Previously printed, in slightly different form, under the title Wasserstrom:The Judicial Decision, 75 ETHIcs 47 (1964) -(University of Chicago Press) [Copyright 1964 by the University of Chicago]. tAssociate Professor of Law, Yale University. 1. WASSERSTROM, THE JUDIcIAL DEcISION (1961). 2. Id. at 6. 3. Id. at 7.