Jealousy is presented as a tragic flaw in Othello—a destructive emotion that brings down an otherwise good man.
Iago, ever on the lookout for people's weaknesses, realizes that Othello—a strong, brave, and honest commander, supremely confident in his career—is insecure in the arena of love. A black man in a racist society and a middle-aged man in an ageist society, he worries that his lovely young wife doesn't truly love him. Iago ruthlessly exploits this fear. He manipulates events to suggest (though he pretends to do so reluctantly) that the handsome Cassio is sleeping with Desdemona. Othello falls for it and "honor kills" his wife as a result.
Shakespeare shows that jealousy is a "monster," a destructive emotion that grows out of all proportion to any reality and destroys lives. It clouds our judgment and becomes a form of madness.
Iago, too, can be seen as a jealous character. It appears as if Iago is so filled with anger and bile that he is looking for any excuse to hurt...
(The entire section contains 3 answers and 712 words.)