The NS Interview: Robert Skidelsky

You lived in Keynes's house for 20 years. Has he always loomed large in your life?
He started to loom large when I was working on my thesis, which became Politicians and the Slump. He seemed to have very good answers to the slump that were never adopted.

What has driven the current financial crisis?
Faith in risk-management models, and the belief that you could reduce all uncertainty to risk. In risk, you have numbers; in uncertainty, you don't. The bankers believed you could work out the odds on anything, like a game of dice or roulette. The pervasiveness of uncertainty seems to be Keynes's central point: those wedded to the efficient market don't take sufficient account of it. It's right at the root of his economics. He rejected probability as a statistical concept and thought of it instead as a logical concept. This was key. If you have probabilities without numbers, you open the barrier to uncertainty: you have knowledge, but it's not precise.