If Iago is detestable enough when he has business on his hands and all his engines at work, he is still worse when he has nothing to do, and we only see into the hollowness of his heart. His indifference when Othello falls into a swoon, is perfectly diabolical.
"Iago. How is it, General? Have you not hurt your head?
Othello. Dost thou mock me?
Iago. I mock you not, by Heaven," &c.
The part indeed would hardly be tolerated, even as a foil to the virtue and generosity of the other characters in the play, but for its indefatigable industry and inexhaustible resources, which divert the attention of the spectator (as well as his own) from the end he has in view to the means by which it must be accomplished.—Edmund the Bastard in Lear is something of the same character, placed in less prominent circumstances. Zanga is a vulgar caricature of it.
