A lot of things that we cannot buy and sell in markets used to be totally legal objects of market exchange - human beings when we had slavery, child labour, human organs, and so on. So there is no economic theory that actually says that you shouldn't have slavery or child labour because all these are political, ethical judgments.

The invention of the printing press was one of the most important events in human history.

Contrary to what professional economists will typically tell you, economics is not a science. All economic theories have underlying political and ethical assumptions, which make it impossible to prove them right or wrong in the way we can with theories in physics or chemistry.

Gone are the days when the upper classes were terrified of the angry mob wanting to smash their skulls and confiscate their properties. Now their biggest enemy is the army of lazy bums, whose lifestyle of indolence and hedonism, financed by crippling taxes on the rich, is sucking the lifeblood out of the economy.

Why do tax havens exist? Because rich countries allow them to. If the U.S. came down on tax havens in the same way they come down on countries that trade with Iran and Cuba, we'd have no tax havens in the world.

I used to joke that I came to England - not to the U.S. where most Koreans go - because I like Arthur Conan Doyle and Agatha Christie.