Iago's Manipulation of Othello

Iago has a truly evil form of manipulation that he uses on specifically Othello.  He follows the old phrase "keep your friends close and your enemies closer."  Throughout the whole novel, he has acted as a kindhearted individual to Othello, but it was just that: acting.  By being a different character in his presence, Iago manipulates Othello without Othello even noticing.  For example, when Othello asks if Cassio was just talking to Desdemona, Iago says, "No, sure, I cannot think it that he would steal away so guiltylike, seeing your coming" (III.iii.41-43).  His saying this implies that Cassio did something wrong without explicitly stating so, which Othello sees as reassuring and eventually influences him.  He does this act several times, convincing Othello to believe what Iago wants him to believe by implying it subtly or pretending to avoid the subject.  Othello believes him so much to be his friend that he even says, "I am bound to thee forever," because he truly thinks that Iago is genuinely trying to help him, which further adds to the magnitude of manipulation (III.iii.249).  His meticulously planned out revenge plot and manipulation is often compared to the devil, and the trust that he creates throughout the play only strengthens that comparison.