 According to Molina, moreover, the ius gentium was not entirely a part of natural law, since it affirmed natural principles but also embodied positive laws, including private property and slavery. Generally, it was in the period between Vitoria and Suárez that natural law was separated from the ius gentium, further divided by Suárez into the ius supra gentes (the law above nations) and the ius inter gentes (the law among nations), which eventually became international law in the strict sense. Natural law and ius gentium were quite close to each other in Roman Law and in Thomas Aquinas; but Vitoria, in his commentary on quaestio 57 in the Secunda secundae of the Summa theologiae, already maintained that, for Thomas, the ius gentium was part of positive law. Suárez makes it clear that, in contrast to natural law, which is inscribed in the heart of human beings and is immutably valid for all of them, the ius gentium is a positive convention among peoples or nations, which is valid for all or nearly for all of them; it includes the right to punish those who are defeated in a just war and, therefore, also the right of enslavement (De legibus II xviii 8).