In most instances, the source material on which playwrights such as Shakespeare based their work clearly explained the causes of their character’s behaviour. But when he was working on Hamlet, Shakespeare decided to try artfully excising such neat and reassuring explanations. In previous versions of the play, Hamlet’s ‘madness’ had been tactical and fake, a ruse to buy time and foster the appearance of harm lessness. But in Shakespeare’s version, his suicidal madness is actually real and, writes Greenblatt, ‘nothing to do with the ghost’ that informed him of his father’s murder.