In 1994, John Forbes Nash Jr received the Nobel Prize in Economics for a one-page note published in 1950. It introduced what today is called the Nash equilibrium, arguably the most basic concept, not just for game theory, but for every model of a social situation where the consequences, for each agent involved, depend not only on their own actions but also on those of the others. In a Nash equilibrium, none of the 'players' has an incentive to change strategy as long as the other players keep to theirs...