Marx's Greatest Error

This was Marx’s greatest error. He assumed the myth that the rich can only get rich at the expense of the poor. One man’s gain must spell another man’s loss. That may be true in a poker game, but not in the real world of business. With the increase of production by better tools, the cost per unit of goods declines (through the law of supply and demand). This makes it easier for people to receive the goods and services, and it raises the poor person’s standard of living. No economic system has been as effective as capitalism in raising the human standard of living.

R. C. Sproul, The Consequences of Ideas p. 144.