THE HISTORY OF INTERNATIONAL LAW AND RELATIONS SINCE THE PEACE OF WESTPHALIA
54. The Main Factors in the Growth of the Science of International Law. -- As already pointed out, the Peace of Westphalia gave to Europe a sort of international constitution which remained the basis of its public law down to the French Revolution. But it would be a serious error to assume that the International Community of States as revealed to the world in 1648 implied the recognition of the science of International Law as understood and practiced by the Society of Nations at the present time. The science of International Law as it exists to-day is a result of slow historical growth and is the product of two main factors, viz. certain theories or principles on the one hand, and international practice or custom recognized as obligatory on the other. The relative value and influence of the contributions of each of these factors is so difficult to determine that they have never been thoroughly sifted or separated -- a task left for the future historians of International Law.
55. The Importance of Jurists and Publicists . -- It is clear that during its formative period International Law was mainly developed by great thinkers and jurists who were forced to rely upon the weight of general ideas or theoretical considerations rather than upon any satisfactory body of accumulated custom, if they desired to ameliorate conditions or improve international relations. The fundamental principles of the science once firmly established and recognized in international practice, there was less need for theoretical discussion. It then became the main function of the jurist and publicist to apply and interpret the law in conformity with the best and most authoritative precedents or usages.
56. Grotius the Founder of the Science of International Law. -- The founder of the Science of International Law was Hugo Grotius, whose main work, entitled De jure belli ac