The science of international law is just as little as any other science an end in itself; it is merely a means to certain ends outside itself. Just as international law, so its science has to keep these ends always in view, and the task of the science stands in the service of these ends. This chapter discusses the tasks of the science of international law and its method. The seven tasks are exposition of the existing rules of law, historical research, criticism of the existing law, preparation of codification, distinction between the old customary and the new conventional law, fostering of arbitration, and popularization of international law. The chapter defines the standpoint from which the science of international law can make use of municipal case-law bearing upon questions of international law. The task of criticism is somewhat connected with another task of the science of international law, namely, that of preparing codification.