This section is from the book "Science Of Legal Method", by Ernest Bruncken. Also available from Amazon: Science of Legal Method.
The formal sources of positive private law (which I have tried to explain [in the preceding chapter]la according to their proper scope and their legitimate use), certainly furnish the best guide, in their peculiar field, for the administration of the law. We cannot conceal from ourselves, however, that even the subtlest and most penetrating interpretation of the positive manifestations of the law will not by itself satisfy all the needs of legal life. Especially - speaking now only of the source of law which at the present day is of all sources the most perfect and fertile, the written law - it is clear that we shall find, if we consider it as we ought, as an act of human intelligence and will, and therefore limited in its outlook and even more limited in its actual effect, that we cannot derive from it the full solution of all the infinite number of questions that clamor for answers in the complexities of social life, no matter how deeply we may dig into the meaning of the statutes, and how ingeniously we may construe them.
There comes a point, accordingly, where the Court can no longer rest secure on a formal rule but must trust to his own skill in finding the proper decision which he is not permitted to refuse.2 Moreover, as long as a lawyer merely searches the statutes for rules that do not depend on his own judgment, he plays no more than la[Not translated.] a receptive or mechanical part. His own skill enters upon the scene when it becomes a matter of discovering and using the underlying principles of every mere statutory rule, which alone make the rule valuable and pregnant. Consequently, if we take the organized body of the positive law as a whole, we may say that the central and normal part to be played by the judge consists in a personal mental activity. The manner in which this activity should be employed it is important to understand.
2 See section 4, French Civil Code.
In the old days, when statutes, and especially statutes relating to private law, were few, fragmentary, and very incomplete, and when even customary law appeared still shifting, loosely fixed, and uncertain, the decision of the judge had a vast field before it, and almost entire freedom of exercising itself. It was immaterial, in this respect, whether the judgment was supposed to be a sort of revelation by the Deity, or based on the less archaic conception that it was an authorized expression of the public conscience.
According as customs have become more firmly established, and especially as statutes have multiplied and extended their application over constantly growing portions of private law, the part played by the personal inspiration of the judge has become narrower and at the same time more accurately defined. It has never disappeared entirely, for the reason that the formal sources have always been incapable, taken by themselves, of covering the whole field of the law. Whenever rules are made by some authority other than the courts, the discretionary functions of the latter invariably become more accentuated although within a more circumscribed sphere. But, at the same time, discretion becomes less arbitrary and subjective. Discretion always remains because it is inherent in the very nature of the judicial function; it has a broader sweep where it can be exercised outside of all formal legal sources, and becomes less complete where it is called upon merely to give effect to such sources of law.
 
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