Iago begins to echo Othello, which makes Othello even more uneasy. He asks questions that are related to the issues at hand, such as whether Desdemona and Cassio have known each other for a while. Othello believes Iago's statements of nothing to be a real attempt to hide the truth about what is going on; he does not that Iago is trying to make him jealous. "Thou echoest me, as if there was some monster in thy thought, too hideous to be shown". Here, Othello creates this simile based on Iago's echoing and unrelated questions, showing how Othello begins to listen to Iago's words.
Iago says that he believes Cassio is "honest"; yet again, this word sets Othello off, and Iago's false uncertainty in his tone makes Othello think that Cassio is a liar. Iago then asks "who has that breast so pure that some uncleanly apprehensions keep leets and law days." In the context in which it is spoken, Othello wants it to mean that Cassio is unfaithful, which is true but we notice how Iago says no names, and doesn't refer the statement to any one. Iago's fakery reaches a point when he speaks of how "good name is the immediate jewel" that people possess. Othello takes the statement to mean that Iago is protecting Cassio's good name by not telling Othello the whole story. Iago here is not saying more than his statements suggest, and all the connections are done by Othello's common sense.
In this scene, we notice jealousy is a major theme; especially with Othello. Specifically Iago soon addresses this. "It is the green-eyed monster," Iago tells him, in that now-famous statement; the "green-eyed monster" becomes a symbol representing Othello's dark feelings, a thought in his mind and beginning to make him think differently. Othello has no idea if there is any truth in these statements, and doesn’t choose to believe them. Othello then begins to say that he believes his wife is not an adulterer.
Othello here uses his black skin as a symbol for how poorly spoken and unattractive he thinks he is. His words are actually more complex and beautiful than those spoken by any other character in the play. Othello doubts that Desdemona could love him, because of his interpretation of himself as being crude, poorly spoken, and old; and because he begins to believe that Desdemona cannot love him, he starts to think she is cheating on him.
Othello begins to use the black/ white imagery found throughout the play, to express his rage at Desdemona's act of adultery. "My name, that was as fresh as Dian's visage, is now begrimed and black as mine own face," Othello says. Iago's "proof" also relies on the animal imagery, which has run throughout the play. He makes Desdemona and Cassio seem like lustful lovers, by describing them as "prime as goats, as hot as monkeys". He says this to make Othello think again about Desdemona.
The handkerchief we now see here is the most crucial symbol and object in the play. To Desdemona, it symbolizes Othello's love, since it was his first gift to her. Othello thinks that the handkerchief, quite literally, is Desdemona's love towards him and when he finds out she has lost it, it must clearly mean that she does not love him anymore.
“Proof” is a key word in this scene; Othello demands that Iago prove Desdemona unfaithful by actually seeing evidence of her guilt. But Iago, who is very clever and persuasive, manages to work around this completely. Othello trusts Iago's words as proof, and is doesn’t know that Iago is being dishonest yet in the play.
Until this point in the play, Othello has spoken with beautiful images, convincing rhetoric, and used his language to express the beauty in his soul. From this point forward, we notice how Othello's use of imagery and story become less and less frequent, and how he begins to rely upon Iago for explanation. Othello is reduced by Iago and his own jealousy to single lines of speech, monosyllabic utterings of "O!" also. Othello begins to lose his power over himself, and over others, when he loses his beautiful language and this marks a huge shift in the balance of power between Othello and Iago, as Iago becomes control the turn taking and begins to steer Othello.
Iago's assumption of Othello's image-filled powers of language, and the beginning of being in control of Othello, is shown by the story he tells of Cassio talking in his sleep. He describes in detail Cassio's actions, making them all too graphic for Othello to forget.
