Let the money lent be money had in the first place rather than something made from nothing.
Paying real interest on something worth nothing is infinite usary.
Discussion
Money (cash) is supposed to be worth nothing .. the only purpose of money is to exchange assets .. and pay taxes .. for example I can't buy Google stock with Apple's .. not even #bitcoin .. I first need to convert in cash - pay tax - and then acquire another asset .. in essence it is something that we are expected to get rid off as quickly as possible..