Investing with Keynes

John Maynard Keynes was a revolutionary economist and a wildly successful investor.

The world knows John Maynard Keynes as the influential economist whose then-radical theories rescued the world from the Great Depression. However, his investing success is less well-known. When he died in 1946, Keynes was worth £480,000, the equivalent of about $30 million now. He was paid well for some of his best-selling books, but he earned little from his work as an economist. Instead, he amassed his fortune largely by investing. He pioneered a brand of common sense trading, or value investing, used more recently by Warren Buffett. Keynes was the most unusual of dismal scientists: a brash economic theoretician who put his knowledge to practical use.

Keynes was born in 1883 in Cambridge, England, where he later studied mathematics and classics at Cambridge University. As a young man, he had little interest in money. He embarked on a career as a civil servant but soon became bored and returned to academia. At Cambridge, he led the Bloomsbury crowd of aesthetes and Bohemians. Called the “Bloomsberries,” this group was renowned for its complicated love triangles and disdain for...