Capitalism needs to be defined!
Capital = currency (fiat curency) The currency used by every country on earth. A Currency that is backed by a promis of a government, not by goods.
Currency comes into existance through debt.
Debt has intrest tied to it.
When currency is created it also carrys with it its intrest burden.
So more curency than is created is needed to repay the debt.
The answer create more currency.