An Elon Musk biographer has sounded the alarm that the world’s richest man may be losing his mind. The Harvard Law-educated biographer Seth Abramson speculated Monday that Musk might be “going mad” in a setting for all to see—brought on by his growing stress,

Since George Washington, presidents have trusted Wall Street and Main Street leaders to put the nation’s books in order, juice the economy or bring efficiency to a lumbering bureaucracy.

European leaders expressed growing frustration with tech billionaire Elon Musk on Monday, as a major row escalated between members of Britain’s government and US President-elect Donald Trump’s key ally.