One would be forgiven for thinking that Robert Greene, author of The 48 Laws of Power, the international bestseller on how to shin up the greasy pole, must be an arrogant megalomaniac living behind security gates in one of Los Angeles’s smartest neighbourhoods. So I am surprised to be greeted by an affable bespectacled man, wearing slightly crumpled clothes, at the door of his Spanish-style bungalow off a busy street in Los Feliz, a bohemian area on LA’s west side.