The Economics of Thomas Aquinas
The degree of manipulation and usury in the farm and food economy is a constant trouble.
Thomas Aquinas on Economics (around 1260):
Thomas Aquinas addressed most economic questions within the framework of justice, which he contended was the highest of the moral virtues. He says that justice is "a habit whereby man renders to each his due by a constant and perpetual will. He argued that this concept of justice has its roots in natural law. Joseph Schumpeter, in his History of Economic Analysis, concluded that "All the economic questions put together matters less to him than did the smallest point of theological or philosophical doctrine, and it is only where economic phenomena raise questions of moral theology that he touches upon them at all."
Thomas Aquinas was careful to distinguish the just, or natural, price of a good from that price which manipulates another party. He determines the just price from a number of things. First, the just price must be relative to the worth of the good. Thomas held that the price of a good measures its quality - "the quality of a thing that comes into human use is measured by the price given for itβ. He goes on to say that the price of a good, measured by its worth, is determined by its usefulness to man. This worth is subjective because each good has a different level of usefulness to every man. Thomas argued, then, that the price should reflect the current value of a good according to its usefulness to man. He continues: "Gold and silver are costly not only on account of the usefulness of the vessels and other like things made from them, but also on account of the excellence and purity of their substance.β
Thomas Aquinas also wrote extensively on usury, that is, the lending of money with interest. He condemned its practice: "to take usury for money lent is unjust in itself, because this is to sell what does not exist, and this evidently leads to inequality which is contrary to justice." Money, and other similar goods, are consumed only when they are used. Charging a premium for money lent is a charge for more than the use of the good. Thus, Thomas Aquinas concluded that the lender is charging for something not his own, in other words, not rendering to each his due.
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Engraving by Cornelis Boel