Doctorates are in demand all over the world, but Germany is where politicians seem to need them most. Of the members of the country's lower house, 114—or nearly one fifth—hold PhDs, and that includes the chancellor, Dr Angela Merkel. This strange love of doctorates helps explain why Germany's defence minister, Karl-Theodor zu Guttenberg, copied parts of his PhD thesis from others, leading ultimately to his resignation on March 1st. By comparison, far fewer American eggheads go into politics. A mere 18 members of the 112th Congress—around 3%—hold a doctoral degree; none of them senators. More than 100 had served in the armed forces. Still, plagiarism, if found out, does not always kill political careers. Joe Biden survived several incidents, before becoming America's vice-president. Russia's prime minister, Vladimir Putin, was accused of copying parts of his PhD thesis. So was Martin Luther King. Muammar Qaddafi's son, Saif, could soon be stripped of his PhD, too. But that is hardly his biggest worry.