say that justice exists by nature, and not because of any definition or principle; just as law does, or right reason, as Chrysippus tells us in his treatise on the Beautiful; and they think that one ought not to abandon philosophy on account of the different opinions prevailing among philosophers, since on this principle one would wholly quit life, as Posidonius argues in his Exhortatory Essays. Another doctrine of Chrysippus is, that general learning is very useful.
And the School in general maintain that there are no obligations of justice binding on us with reference to other animals, on account of their dissimilarity to us, as Chrysippus asserts in the first book of his treatise on Justice, and the same opinion is maintained by Posidonius in the first book of his treatise on Duty. They say too, that the wise man will love those young men, who by their outward appearance, show a natural aptitude for virtue; and this opinion is advanced by Zeno, in his