Today there are three brackets, but since various deductions are phased out as people make more money, the system is more progressive than it looks. Because the rates are progressive, it is necessarily true that a general cut will save higher-income people more both in absolute and relative terms. Look at this example, showing how much different people save in taxes after a 10 percent cut in tax rates. Thus a cut in rates lets the richer Smith keep more money than the poorer Jones, both in absolute and relative terms. There's no injustice here.
Any disparity is merely the result of the partial removal of a prior injustice.
The implications of progressivity are stunning and sadly unappreciated. People with higher incomes pay most of the taxes. According to the IRS, in 1996 the top 50 percent of earners paid more than 95 percent of the income taxes. Frank Levy, an economist at M.I.T., and Iris J. Lav, deputy director of the Center on Budget and Policy Priorities, think they have an answer. Levy and Lav look at free exchange through the eyes of primitives, assuming it is a zero-sum game in which one man's gain is another's loss.