Say, Mill, and the Marxist Critique

Jean-Baptiste Say (1767-1832), a French economist, set out in his Treatise on Political Economy (1803) what became known as Say's Law of markets, often summarized as "supply creates its own demand." Say argued that the very act of producing goods generates income, in the form of wages, rents, and profits, that is then spent on other goods, so that a general glut, or economy-wide overproduction, could not persist, even though particular sectors might temporarily overproduce relative to others. This proposition became a central pillar of classical economics and would later be directly challenged by John Maynard Keynes in the twentieth century.