War must be conducted for the sake of peace, and hence not in such a way as to make peace impossible. It is through this principle that Grotius became the founder of the modern theory of popular sovereignty. 2. When the individual declares war against the state it is an act of rebellion, and, in evident opposition to Althaus, Grotius denies the right of the people to revolt. 3. War between individuals, in a well-regulated state, is limited to justifiable self-defense. 4. War of the state against the individual takes the form of punishment. The state's right to punish must not be construed as the right of expiation. Punishment is justified only in case the pain imposed on the individual contains the possibility of greater good both to the individual himself and to the community.—In all of these various contingencies the authority of the law is independent of theological grounds. It proceeds from human nature (ex principiis homini internis). Human beings congregate and are led to organize societies under the influence of a native social impulse (appetitus societatis); but the constitution of society presupposes certain principles of government—above all the inviolability of every promise—and the people therefore pledge themselves to the observance of these rules either by expressed or tacit contract. The obligation to keep promises, according to Grotius, rests upon a primitive promise. In direct opposition to Althaus, Grotius holds that the people—i. e. after they have constituted society on the basis of the primitive contract—can renounce its sovereignty absolutely because it confers it on a prince or corporation. His theory of the relation of the state to religion, on the other hand, is more liberal than that of the strictly confessional Althaus: The only requirement which the state can make
