XX.1 On commerce
The subjects which follow ought to be treated more extensively, but the nature of this book does not allow for that. I would like to float on a tranquil river, but am carried away by a torrent.
Commerce cures destructive prejudices, and it is almost a general rule that wherever there is benign behavior, there is commerce, and that everywhere there is commerce, there is benign behavior.
We should therefore not be surprised if our ways are less savage than they once were. Because of commerce, familiarity with the ways of all nations has spread everywhere ; we have compared them to each other, and much good has resulted from that.
One cannot say that the laws of commerce improve behavior for the same reason that those same laws degrade it. Commerce corrupts pure behavior  : that was the subject of Plato’s objections ; it polishes and attenuates barbaric behavior, as we see every day.