Iago is the devil
Iago has no conscience, he thinks about himself all through out the play. He tries to ruin everyone's lives just to help his own. A normal person would feel bad about doing these things but not Iago because he is "the devil". But I think none of the things Iago did could of happened if the other characters faults hadn't came into play. If Othello wasn't so insecure, Cassio wasn't hung up on his reputation and Desdemona wasn't so innocent. If these faults wouldn't have came into play on this play I think Iago's plan would have been ruined. So is he the devil? Or maybe he is a smart, manipulative and lucky man.
Iago lies to people through out the play. He tells them what they want to hear. He tells people these things so that they well help him in his big plan.
He doesn't care about anybody but himself, and he would do anything to get his way. Iago is mad at Othello for not picking him to be his lieutenant, so he lies and manipulates people to try and get this position he seeks. First off he goes to Brabantio and tells him about Desdemona's and Othello's marriage. This makes Brabantio extremely mad. He hunts Othello down and they go in front of the senate to sort things out. After Desdemona is fetched and she tells everybody that her marriage to Othello is of her choice so they leave Othello alone. But after this Iago starts to try and break up Desdemona and Othello.
Iago has a good way of making people do what he wants them to do. After Cassio was stripped of his rank he moved in and proposed a plan for Cassio to break up Desdemona...