What makes “Hamlet” different from Shakespeare’s previous work is the way it brings out a complete inner life. Before Hamlet, soliloquy is mostly just exposition of motive. (“Why am I acting this way? Well you may ask. I’m doing it because . . .”—as in “Richard III.”) With Hamlet, as Greenblatt very neatly puts it, we get “an intense representation of inwardness called forth by a new technique of radical excision.” In the original story that Shakespeare drew on, Hamlet’s madness and his delay make complete narrative sense: he feigns madness because he is still a child when his father’s murder by his uncle becomes publicly known; he waits for years, acting like an idiot, until the moment is right for him to strike and claim the throne. Shakespeare, by compressing the plot into a matter of days, making Hamlet full-grown, and having the murder a secret known only to Hamlet, through the Ghost, makes Hamlet’s show of madness not just superfluous but truly self-destructive—it does nothing but draw suspicious attention to him. In any case, Shakespeare’s Hamlet is half-crazy and suicidal before he even sees the Ghost, and most of his soliloquies, instead of furthering our understanding of the action, are at direct cross-purposes to it. (Hamlet knows very well that a traveller has returned from that bourne from which no traveller returns.) What Hamlet says replaces the clear exposition of motive with a kind of chattering, compulsive, image-chasing interior monologue of dreads and desires.

Greenblatt shows that this device is key to the mature tragedies that follow, including “Othello” and “King Lear.” In the original stories, the motives of each of the key characters were perfectly clear: Iago, in the source, is in love with Desdemona; Cordelia refuses to speak because she has been quarrelling with her father about the man she is going to marry. Their behavior is as transparently motivated as that of people in melodramas. Shakespeare, in each case, eliminates the motive in ways that make a mess of the story, and allows it to become something more than a story. His characters have drives that are rooted in who they are, not motives generated by a plot. “What you know you know,” Iago says at last to the man whose life he has destroyed, and there is no more he can say.