He is much less of an Imperialist than Dante, and even his Papalism is not very Imperial. He is very fond of phrases like “a mob of free men” as the essential material of a city; and he is emphatic upon the fact that law, when it ceases to be justice, ceases even to be law.
If this work were controversial, whole chapters could be given to the economics as well as the ethics of the Thomist system. It would be easy to show that, in this matter, he was a prophet as well as a philosopher. He foresaw from the first the peril of that mere reliance on trade and exchange, which was beginning about his time; and which has culminated in a universal commercial collapse in our time. He did not merely assert that Usury is unnatural, though in saying that he only followed Aristotle and obvious common sense, which was never contradicted by anybody until the time of the commercialists, who have involved us in the collapse. The modern world began by Bentham writing the Defence of Usury, and it has ended after a hundred years in even the vulgar newspaper opinion finding Finance indefensible. But St. Thomas struck much deeper than that. He even mentioned the truth, ignored during the long idolatry of trade, that things which men produce only to sell are likely to be worse in quality than the things they produce in order to consume. Something of our difficulty about the fine shades of Latin will be felt when we come to his statement that there is always a certain inhonestas about trade. For inhonestas does not exactly mean dishonesty. It means approximately “something unworthy,” or, more nearly perhaps, “something not quite handsome.” And he was right; for trade, in the modern sense, does mean selling something for a little more than it is worth, nor would the nineteenth century economists have denied it. They would only have said that he was not practical; and this seemed sound while their view led to practical prosperity. Things are a little different now that it has led to universal bankruptcy.
— G. K. Chesterton