Catholic Roots of International Law

Many of the modern political, governmental, educational and social structures throughout the world were founded upon principles developed by Catholic priests and laity and a terrific book which touches on all of these is How the Catholic Church Built Western Civilization.

International law is one such area developed by Catholic priests and in this excerpt from the book, the author focuses on the rights of Indians and other aboriginal people during the Spanish exploration in the New World.

“Among the most illustrious of these thinkers was Father Francisco de Vitoria [born 1483]. In the course of his own critique of Spanish policy, Vitoria laid the groundwork for modern international law theory, and for that reason is sometimes called “the father of international law,” ….

“Vitoria borrowed two important principles from Saint Thomas Aquinas: 1) the divine law, which proceeds from grace, does not annul human law, which proceeds from natural reason; and 2) those things which are natural to man are neither to be taken from nor given to him on account of sin. Surely no Catholic would argue that it is a less serious crime to murder a non-baptized person than a baptized one. This is what Vitoria meant: The treatment to which all human beings are entitled—e.g., not to be killed, expropriated, etc.—derives from their status as men rather than as members of the faithful in the state of grace. Father Domingo de Soto, Vitoria’s colleague at the University of Salamanca, stated the matter plainly” “Those who are in the grace of God are not a whit better off than the sinner or the pagan in what concerns natural rights.”

“From these principles adopted from Saint Thomas, Vitoria argued that man was not deprived of civil dominion by mortal sin, and that the right to appropriate the things of nature for one’s own use (i.e., the institution of private property) belonged to all men regardless of their paganism or whatever barbarian vices they might possess. The Indians of the New World, by virtue of being men, were therefore equal to the Spaniards in matters of natural rights. They owned their lands by the same principles that the Spaniards owned theirs. As Vitoria wrote, “The upshot of all the preceding is, then, that the aborigines undoubtedly had true dominion in both public and private matters, just like Christians, and that neither their princes nor private persons could be despoiled of their property on the ground of their not being true owners.” (pp. 137-139, italics in original)