A flat tax is roughly the same as a sales tax.

The upshot is that to send its children to a school of even average quality, a family must outbid half of other similar families who are pursuing the same goal. And that's become dramatically more expensive because of the growth in median house size, which was in turn caused by higher spending at the top.

Virtually all families in the middle of the earnings distribution aspire to send their children to a school of at least average quality. (We'd think ill of any parent whose aspirations were lower.) The rub is that the best schools tend to be located in more expensive neighborhoods.

In almost every instance, air and water quality goals were met more cheaply and quickly when we taxed pollution than when we tried to regulate it directly.

As the great naturalist Charles Darwin saw clearly, individual and collective interests often coincide, as in the invisible hand narrative. But he also saw that in many other cases, interests at the two levels are squarely in conflict, and that in those cases, individual interests generally trump. That simple observation suggests that market failure is often the result not of insufficient competition (the traditional charge from social critics on the Left), but of the very logic of competition itself.

Prescriptive regulations, such as telling electric utilities what kinds of coal to burn or what kinds of scrubbers to install on their smokestacks, were not only intrusive, they were also grossly inefficient.

Once firms had to pay to pollute, they became incredibly inventive at figuring out cheaper ways to eliminate their SO2 emissions.