The political theory of the seventeenth century, therefore, showed but little objectivity. As in metaphysics, so in political philosophy, whereas the form was often subjected to the mathematical method so valued for its success in the physical sciences, this form was little but a disguise for a more practical purpose, conscious or unconscious. The growth of nationalism also divided the commonwealth of Europe. Bursting the bonds of the old Roman imperial tradition, great national states arose, animated by an intense patriotism, and acknowledging no law but that of force. Machiavelli was their prophet, and the “reason of state” their gospel—a maxim of policy expressing the idea that the public interest is justice and humanity, that might makes right, and that the safety of the people is the highest law. A more thorough and successful attempt firmly to found and clearly to formulate international law was made by Hugo Grotius, commonly regarded as the father of this branch of jurisprudence.