Sociologist Geoffrey Ingham presents two grand theories of money – the commodity theory and the credit (or claim) theory. He follows the great economist Joseph Schumpeter in seeing these theories as incompatible. Money is either a commodity or a claim. According to the first, money evolved from barter. It gains value from the material that it consists of or is tied to (eg, gold or silver). According to the second, its value derives from the debts He follows the great economist Joseph Schumpeter in seeing these theories as incompatible. Money is either a commodity or a claim. According to the first, money evolved from barter. It gains value from the material that it consists of or is tied to (eg, gold or silver).