Introduction
realm of causality is likely to assert too much. It is entirely clear to us now that there was an important element of truth in the theory of an unconscious development of law; it is equally apparent that the principle of purpose is also true. The error lies only in claiming an exclusive operation for either theory of law. It is, however, one of the most interesting phases of historical study to trace out the actions and reactions of ideas, and Jhering was a man who was able to do this with a lofty and inspired outlook on the manifold complication in the restless flow of life. The ascending spiral of evolution of juristic thought is plainly visible, to speak only of recent centuries, in the age of rationalism with its revolutionary by-product which gave way to an era of reactionary conservatism in the Historical School, and which later is supplanted by the epoch of legislation and socialization of the law. But, now, to attempt a simple generalization of causality in history, even with our better fortified knowledge, and in the light of an
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