How markets fail

John Cassidy describes the rising influence of what he calls utopian economics--thinking that is blind to how real people act and that denies the many ways an unregulated free market can produce disastrous unintended consequences. He then looks to the leading edge of economic theory, including behavioral economics, to offer a new understanding of the economy--one that casts aside the old assumption that people and firms make decisions purely on the basis of rational self-interest.