according to the philosopher.  Now “slavery belongs to the law of nations,” as Isidore states.  Therefore the right of nations is a natural right.’[1] In answer to this objection St. Thomas draws the distinction between what is natural absolutely, and what is natural secundum quid, the passage which we have quoted in treating of property rights.[2] He then goes on to apply this distinction to the case of slavery.  ’Considered absolutely, the fact that this particular man should be a slave rather than another man, is based, not on natural reason, but on some resultant utility, in that it is useful to this man to be ruled by a wise man, and to the latter to be helped by the former, as the philosopher states.  Wherefore slavery which belongs to the law of nations is natural in the second way, but not in the first.’[3] It will be noted from this passage that St. Thomas partly admits, though not entirely, the opinion of Aristotle.  In the De Regimine Principum he goes much further in the direction of adopting the full Aristotelian theory:  ’Nature decrees that there should be grades in men as in other things.  We see this in the elements, a superior and an inferior; we see in every mixture that some one element predominates....  For we see this also in the relation of the body and the mind, and in the powers of the mind compared with one another; because some are ordained towards ordering and moving, such as the understanding and the will; others to serving.  So should it be among men; and thus it is proved that some are slaves according to nature.  Some lack reason through some defect of nature; and such ought to be subjected to servile works because they cannot use their reason, and this is called the natural law.’[4] In the same chapter the right of conquerors to enslave their conquered is referred to without comment, and therefore implicitly approved by the author.

[Footnote 1:  II. ii. 57, 3.]

[Footnote 2:  Supra, p. 64.]

[Footnote 3:  II. ii 57, ad. 2.]

[Footnote 4:  De Reg.  Prin., ii. 10.]

‘Thus,’ according to Janet, ’St. Thomas admits slavery as far as one can admit it, and for all the reasons for which one can admit it.  He admits with Aristotle that there is a natural slavery; with St. Augustine that slavery is the result of sin; with the jurisconsult that slavery is the result of war and convention.’[1] ’The author justifies slavery,’ says Franck, ’in the name of St. Augustine, and in that of Aristotle; in the name of the latter by showing that there are two races of men, one born to command, and the other to obey; in the name of the former in affirming that slavery had its origin in original sin; that by sin man has forfeited his right to liberty.  Further, we must admit slavery as an institution not only of nature and one of the consequences of the fall, we must admit a third principle of slavery which appears to St. Thomas as legitimate as the other two.  War is necessary; therefore it is just; and if it is just we must accept its consequences.  One of these consequences is the absolute right of the conqueror over the life, person, and goods of the conquered.’[2]