Othello

     The theme of jealousy really begins becoming apparent in Act III of Othello by William Shakespeare.  Iago is very smart and begins to make Othello feel a spark of jealousy at the moment he sees Cassio leave Desdemona.  Iago says that Cassio was the one to leave but he was not sure because he did not think "that he would steal away so guilty-like. . . " (III.iii.40).  He needed this moment to stir Othello's feelings about whether his wife was being faithful or not.  Othello gets even more jealous when Iago lies to him telling him that Cassio had a dream about Desdemona.  His jealously becomes so huge that even when he does not have factual proof, he still believes Iago.  Jealously and doubt begin to fill Othello's mind even though he has no reason to think like that because Desdemona has done nothing to him.  Jealously will end up being the cause of all of the other events that are to come.  Othello already said that he wants Cassio dead.  He is so angry that he believes Iago's lies.  All Iago had to do was make Othello a little jealous.