Many C.E.O.s receive a lot of stock and stock options. Over time, they and other rich people earn a lot of money from the capital they have accumulated: it comes in the form of dividends, capital gains, interest payments, profits from private businesses, and rents. Income from capital has always played a key role in capitalism. Piketty claims that its role is growing even larger, and that this helps explain why inequality is rising so fast. Indeed, he argues that modern capitalism has an internal law of motion that leads, not inexorably but generally, toward less equal outcomes. The law is simple. When the rate of return on capital—the annual income it generates divided by its market value—is higher than the economy’s growth rate, capital income will tend to rise faster than wages and salaries, which rarely grow faster than G.D.P.
Another piece on Piketty, more balanced than the Guardian interview and with some additional interesting insights into the emergence of “supermanagers” and the important point that economics and politics must be studied together.