As you read, look for the themes and elements described below:
Contrasts: Animals, animal instincts vs. the divine or “higher” nature:
Iago plays on other characters' emotions by suggesting that Othello is more animal than human. Pay special attention to any mention of animals, beasts, and hunting.
Desdemona is often called “divine” by Othello and others. Note the contrast between high and low, and between heaven and hell, both within the play and within individual characters. What makes a person's “baser” nature come out?
Where does Iago's nature fit in this scheme?
Racial elements also provide a point of contrast and conflict that the characters are quick to use to exploit when it is convenient for them to use it to denigrate Othello.
Soldiers and civilians:
Othello admits that he knows little of the “civilized” world; his place is in battle. He considers himself unrefined. Who else brings up the different worlds of war and peace, rude and polite? Do these worlds ever intersect?
Self-knowledge: Until he begins to suspect Desdemona, Othello is able to remain calm in the midst of chaotic situations (when he is dragged before Brabantio, for instance, or when he comes upon the brawl in Cyprus).
Once he has been infected by doubt, however, he cannot go back to his previous beliefs, no matter how much he would like to. His rage skews his judgment and colors everything he sees-–notice how the handkerchief, a cherished token of his courtship and marriage, takes on new symbolism when his faith begins to unravel. How clearly does Othello see his own fall?
Dramatic irony: Iago makes his plans known to the audience through asides— addresses to the audience that the other characters cannot hear, or when alone on stage. The tension between the ignorance of Othello, Desdemona, Cassio, and Roderigo and our knowledge of what is going to happen to them heightens the drama of the play.
Double entendre: A double entendre is a play on words, especially one having sexual overtones. Iago uses many of these, especially when he wishes to poison the mind of Othello with doubts.
Language: Follow Othello's language as he falls apart, remembering that, in Shakespeare's time, “You” was used for polite address, while “Thee” and “thou” indicated a lack of formality.