Shakespeare, 'Othello', title - 'Act 3 begins in love and ends in jealousy. Account for the shift in Othello's feelings towards Desdemona'

Both scenes 1 and 2 in Act 3 are very brief, and do not give us any insight into shifts in feelings. Scene 3 is crucial, however, because it is the pivotal scene where Iago convinces Othello that both his wife and Cassio have committed adultery. At the end of the scene, Othello decides to take revenge by murdering them both with Iago's help. Iago is also promoted to lieutenant and pledges his loyalty to Othello. Iago is the …

…violent jealousy to the extreme of wanting death as his revenge. Her ignorance to the situation is working against her, as she continues to plea for Cassio's case, which, to Othello, is stronger evidence of their affair. Iago's clever manipulations of Othello, and situations as they arise, have led to him being in complete control. The path, which the play is to take from here, is most definitely going to be one of ironic tragedy.