People have been gambling, in one form or another, for as long as history itself. Why? Money, entertainment, escape and a desire to win are all traditional explanations. Arguably, however, these are secondary considerations to a higher order purpose: a craving for control. Gambling offers a means of gaining authority over the unknown, granting us a sense of control over uncertainty. A successful gambler provides confirmation that he is ‘somebody’, who has beaten the system, who has won with wits, and conquered the unknown. Whilst for the majority this sense of control is largely illusory – almost everything that happens in gambling, whether betting or stock market investing, is luck – it is no less rewarding. Merely feeling in control reduces anxiety and a sense of helplessness, and enhances motivation. The wonderful contradiction is that our craving for knowing, meaning and certainty is motivated by the very quality that makes gambling largely unknowable, unconquerable and uncontrollable: randomness. Science is teaching us that the uncertainty of rewards, rather than the rewards themselves, is what drives a curious mind. Gambling presents itself as a kind of elixir of knowledge; ultimately it disappoints but has us coming back for more. This is the addictive power of maybe.