Some persons regard all Justice as thus conventional.

They say--'What exists by nature is unchangeable, and has everywhere the same power; for example, fire burns alike in Persia and here; but we see regulations of justice often varied--differing here and there.' This, however, is not exactly the fact, though to a certain extent it is the fact.

Among the gods indeed, it perhaps is not the fact at all: but among men, it is true that there exists something by nature changeable, though everything is not so.

Nevertheless, there are some things existing by nature, other things not by nature.

And we can plainly see, among those matters that admit of opposite arrangement, which of them belong to nature and which to law and convention; and the same distinction will fit in other cases also.