 What could be wrong with lending at interest? Some of the more obscure arguments concern the nature of money (again): Aristotle argued that there is something unnatural with “money begetting money”. While he allowed that money is a useful means for facilitating commercial exchange, Aristotle thought that it has no productive use in itself and so receiving interest over and above the borrowed amount is unnatural and wrong (Politics, 1258b). A related argument can be found in Aquinas, who argued that money is a good that is consumed on use. Although a lender can legitimately demand repayment of an amount equivalent to the loan, it is illegitimate to demand payment for the use of the borrowed amount and so adding interest is unnatural and wrong (Summa Theologica, II–II, Q78).