In international law, unlike the other branches of legal science, positivism is still a determining influence. Positivist philosophy restricts the object of scientific knowledge to matters that can be verified by observation, and thus excludes from its domain all matters of an a priori, metaphysical nature. Positivism accepted the breakdown of the great metaphysical systems of the eighteenth and the early nineteenth centuries and the resulting decadence of metaphysical jurisprudence as an established fact. Positivism transplanted schematically the highly refined positivist method of formalist and conceptualist interpretation into the domain of international law. The legacy which positivism has left to the science of international law consists in the task of comprehending the international law of a given time as standing in a dual functional relationship with the social forces of this time. Positivism transplanted schematically the highly refined positivist method of formalist and conceptualist interpretation into the domain of international law.