200 HARVARD LAW REVIEW. such absolute demarcation is possible in a question depending on such varied circumstances. It is the duty of the judge to apply the law to such facts as come before him. He must perform his office with wisdom and justice, guided by a method of reasoning which the practice of English courts for centuries has made familiar. So far as this process, carried out as his predecessors have done before him, results in legislation, such legislation is legitimate and necessary. No more precise rule can be laid down to meet all cases. 3. How far may the judge in carrying on this process under- take to discard old doctrines and substitute new ones as society appears to require it? Here again no absolute rule can be laid down. It may happen that a change of customs makes a change in the law so plainly necessary that it is mere good sense for the court to give effect to it, as was done, for example, in a branch of the law depending preeminently upon custom, by the American decisions which recognized the negotiability of bonds. 1 In gen- eral the maxim cessante ratione cessat ipsa lex might well have been given a far wider application. The history of our law shows repeated instances where courts have failed, through an unreason- ing conservatism, to cut away technicalities utterly meaningless and having their origin in conceptions long since passed away; and the law as a science has suffered accordingly. A certain amount of judicial legislation of this kind might properly be regarded as incidental to the mere wise and just administration of the law. But no such step should be taken without great caution and a knowledge of all its bearings. The proper tendency for modern courts is not to be found by considering the acts of great judges in the past, whatever their services to the law, who were acting under other surroundings and influences; it depends on the conditions of our own time. We live under a government where access to the legislature is easy. Since the abolition of the old forms of action legal reasoning, formerly confined, as it were, to so many separate circles, is carried on in one broad field. In our twofold system of law and eqi' : ty we have a body of rules and principles which, properly understood, can do much ; and the true means to the more perfect development of this system does not 1 See White v. R. R. Co., 21 How. 575. In England a similar result is apparently reached by the more indirect method of estoppel. See In re Romford Canal Co., 24 Ch. D.85.
