Who can predict what he will do next? Back in 1987, one of the world’s most celebrated experts opined: “Sad to say, the poor fellow has incurable emotional problems. At times he feels euphoric and can see only the favorable factors?.?.?.?At other times he is depressed and can see nothing but trouble ahead.”

It might seem like an armchair diagnosis of the ever volatile Donald Trump, whose first inauguration speech conjured a vision of “American carnage”, while his second was “confident and optimistic that we are at the start of a thrilling new era of national success”.

“[He] has another endearing characteristic,” the diagnosis went on. “He doesn’t mind being ignored.” Not Trump, then. No, the psychotherapist was the world’s most celebrated investor, Warren Buffett. Lying on Mr Buffett’s couch for psychoanalysis was a hapless gentleman named Mr Market.