L'evoluzione del concetto di giustizia nella teoria giusnaturalistica di Ugo Grozio

Grotius writes the De Jure belli ac pacis (1625) almost twenty years after his first treaty of natural law, the De Jure praedae (1604-06). In this lapse of time he directly experiences prison and exile, due to his adherence to Arminianism. A comparative reading of these two works of Ugo Grotius allows us to highlight the internal evolution of the author’s thought on a central theme of his philosophical-political doctrine, which is that of justice. For this reason, a parallel between these two works about jus naturae and jus gentium allows us to fully understand how much the author’s adhesion to Arminianism has affected Grozian reflection on natural law. After this adhesion —as it is known— Grotius distances himself from orthodox Calvinism, hence he rejects its most extreme theses, which denied any merit to human action and indicated only the will of the Lord expressed in the Holy Scriptures as the source of morality. Consequently, the Dutch natural lawyer in his maturity adopts a rationalistic ontology. Therefore, he identifies the origin of natural law no longer in the divine creative will, but in the metaphysical values of good and evil, which were conceived as pure rational essences, independent of the voluntas Dei. Thus, it is evident that the two international Grotian treaties express a different ontological conception. On the basis of these assumptions, the present essay aims to highlight how interesting a comparison between these two works is in terms of justice. As a matter of fact, they start from a different definition of the justum, even though both of them connect the justice with the guarantee of enjoyment by each one of what he owns. More specifically, in the De Jure praedae the author still shares the Aristotelian conception of justum as a medium. In De Jure belli ac pacis, instead, he adopts a purely negative notion of justice, which, in his opinion, would consist in abstaining from the ‘suum’ of others. With the Latin word ‘suum’ Grotius means especially what belongs to the sphere of the individual’s moral personality, which no one can harm without doing an injustice. The doctine of suum then becomes central in Grotius’s mature juridical doctrine.