In Iago’s deception of Othello, Roderigo, who loves Desdemona, is one of Iago’s stepping stones for his treacherous scheme. Iago was able to grasp the circumstances and maneuver Roderigo’s desires and emotions to work for him. He knows Roderigo is obsessively in love with Desdemona and jealous of her husband, Othello. As Roderigo says, “It is silliness to live when to live is torment,” he is plagued by love and this weakness is discovered by Iago (1.3, 350). With his mastermind, Iago gains an ally for his wicked plan by deceitfully assuring Roderigo that he will help him attain Desdemona. Also, Iago successfully convinces Roderigo that “Desdemona is directly in love with Cassio”, subsequently manipulating Roderigo’s jealousy and resentment toward Cassio (2.1, 240). Roderigo, who unaware of Iago’s purpose, consents to join Iago’s plot and helps Iago removes Cassio from the lieutenant position by provoking a fight with him. Thus, Cassio’s demission progresses Iago’s plan of fabricating the affair between Cassio and Desdemona. Iago effectively manipulated Roderigo to both provide streams of wealth and discredit Cassio. On the other hand, Cassio is playing an important part in Iago’s deception of Othello as well. In Cyprus, when Cassio states that “I have a very poor and unhappy brain for drinking.” (2.3, 34), Iago realizes his vulnerability and devises a situation that “may offend the isle.”(2.3, 59) for Cassio. Although Cassio resists, he is convinced by Iago that drinking is appropriate under certain circumstances and get drunk. Iago now asks Roderigo to provoke Cassio to fight, which finally results in Cassio being demoted. At this moment, by reinforcing Cassio’s fear of “lost reputation” (2.3, 281) with lies and innuendo, Iago drives Cassio in a position to “confess yourself to [Desdemona]; importune her help to put you in your place again.”(2.3, 318) Due to Iago’s advice, Cassio’s approaching to Desdemona then enhances Iago’s deception of Othello. Also, by stealing Desdemona’s handkerchief, Iago is able to plant it on Cassio and use it as evidence for his lies. Iago’s thorough schemes to disgrace Cassio at first and then concoct the affair between Desdemona and Cassio makes him unknowingly serve in Iago’s vengeance on Othello.
Finally, Iago’s manipulation of Othello himself is the main part of his deception. First, Iago uses Othello’s race to create doubt in his mind: “Whereto we see in all things nature tends.” (3.3, 232) and mentions the women of Venice that “their best conscience is not leave’t undone, but kept unknown.”(3.3, 203). Moreover, Iago arranged for Othello to overhear a conversation between himself and Cassio so that Othello believes he is hearing a confession. Knowing the doubt in Othello, Iago begins lying and providing hints like “in sleep I heard [Cassio] say, ‘Sweet Desdemona, Let us be wary, let us hide our loves!’…the Moor” (3.3, 416) He uses Cassio’s youth, good looks, and friendship with Desdemona to play on Othello’s insecurities about Desdemona’s fidelity. Thus, because Iago is able to exploit Othello’s jealousy and insecurities, he successfully deceives Othello and finally accomplishes his revenge.
Although Roderigo, Cassio, and Othello have different weaknesses, Iago successfully utilizes the weaknesses to ultimately gain vengeance with an impression of honesty and sincerity. Iago’s elaborate scheme is full of skills and thoughts, assisted by some opportunistic circumstances like Desdemona’s loss of handkerchief, which becomes a significant instrument in Iago’s plan.