Medici Money: Banking, metaphysics and art in fifteenth-century Florence

It is King Agamemnon who rules the mad round of exchanges that begins the Iliad, and it is the king whose head, in centuries to come, would always appear on coinage. Divinely appointed, the monarch sanctions and governs the practice of exchange, which is to say the economic relationships among the subjects he rules. The process was much speeded up now, of course, for money enables us to sell to one person, store our wealth, then buy from another. We don’t have to cast about for that unlikely individual who has exactly what we want and wants exactly what we have. All the same, as long as money is made up of a precious metal that has value in itself as a commodity, then nothing fundamental has changed. We sweat to produce, as God told us we must when He threw us out of paradise; we sell our wares for a certain weight of gold or silver or copper, then use that, or part of it, to buy what someone else has sweated to produce. True, some perverse parallels arise: We can now compare the unit cost of a whore with that of a flask of wine, or a copied manuscript, or a prayer for the dead. But everything is still more or less in order and everyone in his place.

Usury alters things. With interest rates, money is no longer a simple and stable metal commodity that just happens to have been chosen as a means of exchange. Projected through time, it multiplies, and this without any toil on the part of the usurer. Everything becomes more fluid. A man can borrow money, buy a loom, sell his wool at a high price, change his station in life. Another man can borrow money, buy the first man’s wool, ship it abroad, and sell it at an even higher price. He moves up the social scale. Or if he is unlucky, or foolish, he is ruined. Meanwhile, the usurer, the banker, grows richer and richer. We can’t even know how rich, because money can be moved and hidden, and gains on financial transactions are hard to trace. It’s pointless to count his sheep and cattle or to measure how much land he owns. Who will make him pay his tithe? Who will make him pay his taxes? Who will persuade him to pay some attention to his soul when life has become so interesting? Things are getting out of hand.

Contro natura! thunders the Church — against nature. Usury is unnatural and God punishes it with the plague, warns the preacher Bernardino of Feltre. To defend themselves from the plague, the merchants of Florence pay for an expensive bronze door showing one of the strangest exchanges ever made, or at least proposed: Abraham’s sacrifice of Isaac. Ghiberti’s doors were so beautiful they were “fit to be the gates of paradise,” said Michelangelo. And he was gay. Contro natura, thunders the Church. In Dante’s hell, sodomites and usurers are punished in the same place, the third ditch of the seventh circle where flakes of burning ash sift for all eternity on an unnatural landscape of scorching sand. The sodomites are forced to exist (how can we say live?) in an unnatural perpetual motion. The usurers are forced to sit unnaturally still, as they did at their accounts. Only their hands move rapidly and unnaturally, as once they moved counting coins or writing bills that have no currency beyond the grave. Their faces are disfigured. Grief bursts from the eyes they ruined over their registers. Unaided by Giotto’s frescoes, Reginaldo degli Scrovegni is down there: “He twisted his mouth and stuck out his tongue like an ox that licks its nose.” Contro natura!

The other inmates of that infernal ditch are the blasphemers. It is unnatural to curse your creator. None of these three sins is considered such today. If a man, today, negotiates a mortgage with a client in the afternoon, has sex with his male lover in the evening, and blurts out, “Christ Almighty,” when the alarm starts him from sleep in the morning, we have no difficulty thinking of him as a decent bloke. Or not in the West. In an Islamic state, all three actions are punishable. For the Koran will no more permit the lending of money at an interest than it will allow Salman Rushdie to deride the name of Muhammad, or two consenting males to make love. Usury makes money “copulate,” said the theologians, quoting Aristotle. Which is unnatural.

If you still find this hard to grasp, you’re in good company. “Go back a little way,” Dante’s pilgrim poet begs his guide Virgil as they hurry through hell, “to where you told me that usury offends God’s goodness, and untie that knot for me.” He can’t quite see it. Summarizing Thomas Aquinas, Virgil explains that “nature takes its course from heavenly intellect,” and that “human toil, as far as it is able, follows nature, as the pupil does his master, so that it is God’s grandchild, as it were.” In short, God creates work to complete man’s nature. Refusing work, the usurer rejects nature, rejects the way God has chosen for him, insults God’s grandchild.