In Shakespeare's Othello, Iago successfully manipulates others through treachery. Iago uses not only his impeccable ability to appear as something he is not, but he also finds clever ways to abuse the trust of others in order to achieve his goals. Iago uses his knowledge of Roderigo's love for Desdemona in order to manipulate Roderigo into following his every order. Iago exploits Cassio's weakness against alcohol in order to remove him from the role of lieutenant, and Iago subtly insights suspicion within Othello through insinuating lies about the person Othello cares most about. .
Iago leads Roderigo to believe that he will assist him in winning Desdemona's heart. Iago initially convinces Roderigo not to commit suicide for love "is merely a lust of the blood and a permission of the will" (1.3.377-378). Iago uses his belief that love is nothing more than a longing for physical pleasure in order to convince Roderigo that it would be ridiculous to commit suicide over an uncontrollable human instinct. In preventing Roderigo from killing himself, Iago can use Roderigo's money for his own personal gain as well as his trust in order to manipulate Roderigo into committing acts that will help Iago achieve his overall plan. Throughout the play, Roderigo also has his doubts about Iago's plan, but Iago continues to use his manipulative abilities to keep Roderigo's faith. At one point, Iago persuades Roderigo to continue with his plan through the falsehood that Cassio has replaced Othello as commander and chief of the Venetian army. Iago lies to Roderigo, claiming that Othello is being sent to Africa, and that the only way to prevent Othello from taking Desdemona to Africa along with him is to eliminate Cassio. Of course the death of Cassio will greatly satisfy Iago's thirst for revenge, for Iago claims that "if Cassio do remain, he hath a daily beauty in his life that makes me ugly" (5.1.19-21).