Example: Act 1 Scene 1 Lines 94-95
The way Iago described Othello and Desdemona’s marriage to Brabantio made it sound as if Desdemona did not want to marry Othello, and it made Brabantio hate Othello even more.
1a. Iago’s anger is based off of Cassio being promoted higher than him. He promises to betray Othello the first chance he gets (because of his anger) Act 1 Scene 1 Line 67
Iago was also able to manipulate Roderigo. In Act 1 Scene 1 Lines 329-351, Roderigo is being “tormented” by his love for Desdemona, but Iago talks him out of drowning himself and talks him into going to Cyprus and assures him that everything will work out. But really all Iago wants to do is use Roderigo in his plan to kill Othello.
2. Jealousy is much more likely to motivate a person to action. In Act 3 Scene 3 Lines 170-172 Iago says that jealousy is “the green-eyed monster”. He knows how much jealousy can affect people, so he uses it to his advantage.
In Act 3 Scene 3 Lines 331-334, Iago shares with the audience his plan to trick Othello with the handerchief. He knows that Othello is already suspicious of Desdemona cheating on him, so he knows that something as simple as the handkerchief is seen as a big hint to Othello.
3. I think that race played a part in Othello and Desdemona’s marriage. From the beginning, many people were against their marriage (Roderigo and especially Babantio). (Act 1 Scene 2 Lines 283-301). Brabantio expresses his disapproval of Othello and Desdemona’s marriage.
Iago was a relatively high-ranked officer, but he thought that he was more qualified for the lieutenant position than Cassio, and that jealousy motivated his anger/actions toward Othello.
Act 1 Scene 1 Lines 20-33- this passage displays Iago’s jealousy/reasoning.