What motivated Iago to follow through with his schemes? Do you think Iago is a madman, the devil incarnate, or a rational human being?
Iago is a well-rounded character who has complex motivations for his actions. First, he is a racist who dislikes Othello, and, in fact, everyone not of an old Venetian family. He has a great sense of entitlement and is bitter when the world does not give him the advantages he thinks he deserves. He is especially angered by Othello choosing Cassio rather than himself for promotion, and then he plots revenge against Othello.
He is definitely an angry, embittered, and nasty man and the villain of the play. On the other hand, he is not insane, and once he has decided to obtain his revenge is capable of executing complex long-term plots in a cool and rational fashion. He also is not the devil incarnate but rather shows the corrosive effects of jealousy on human beings. In this way, he is parallel to Othello, whose character flaw is also jealousy.
In Shakespeare's classic play Othello, Iago is the antagonist, who expresses his resentment and motivation to destroy Othello in the first scene of the play. In the opening scene of the play, Iago tells Roderigo that he hates Othello for choosing the intelligent yet inexperienced Florentine, Michael Cassio, to be his lieutenant and second-in-command. Iago raves that he is much more qualified to be Othello's lieutenant and believes that he deserves the high-ranking position more than Cassio. He goes on to tell Roderigo that his military career has been unceremoniously cut short by Othello and expresses his deep resentment towards the general. In addition to feeling humiliated for not being appointed lieutenant, Iago also seems to have always disliked the idea of Othello, a foreigner, being his superior. Iago also suspects that Othello slept with his wife, Emilia, which strengthens his desire for revenge.
One could argue that Iago is a rational human being who is motivated for revenge by common human emotions. Iago is fueled by jealousy, resentment, and bitterness, which are typical emotions that influence individuals to seek revenge. Iago further proves that he is a rational, callous person by cleverly manipulating Othello, Cassio, Roderigo, and Desdemona in order to attain his goal of destroying Othello's happiness. Despite Iago's vindictive, crafty personality and cruel intentions, he has plausible reasons to seek revenge and is not some madman who randomly slaughters innocent people.
Shakespeare does not releal Iago's motivation until the end of the play. In Act V Iago states that he can't stand Cassio having anything beautiful in his life as it makes him (Iago) ugly by comparisson. Iago contrives reasons throughout the play to justify his "schmes." All of these reasons only serve to ultimately show how "small" Iago really is. His only true motivation is envy. He is smart though as he seizes every opportunity to exploit a situation.
In my opinion, Iago is not mad, not the "devil incarnate" and completly rational. Iago is motivated by the all-too-human propensity for envy. He is envious of Othello's station in life and all that that positon brings: political power, money, even beautiful women.
Iago is far too organized to be mad, his schemes too well planned. He is the one to inform Othello's father, the Duke, of Othello and Desdemona's elopement, knowing full well the havoc the news will create. He is there, behind the scenes, til his (and Othello's) bitter end.
Other critics have called Iago "a machiavellian villan without conscience," and indeed, Shakepeare describes Iago in the play as a "viper" and an "inhuman dog." And he does seem to be so.
However, what continues to make Shakespeare's plays so universally appealing is that their themes are still easily identifiable. Yes, evil exists in the world, often cold, calculated evil. It seems that backstabbing and political manuevering is nothing new. Just look at any number of headlines today.