Peter Drucker, who has died at the age of 95, hated being labelled as a “guru”. But that is what he was for thousands, probably millions, of managers. Never mind that the dictionary definitions of the word range from “venerable” and “weighty” to “mediator of divine truth.” To Drucker, guru was synonymous with “charlatan”. He preferred to be known, he often said, as “just an old journalist”.

As so often in his life, he was indulging not so much in false modesty as in good-humoured self-mockery. For he was manifestly very much more than that.