How do quotations illustrate the theme of loss in Othello?
Othello loses everything in Shakespeare's Othello. It is interesting to note that it is the loss of a handkerchief which allows Iago to create a situation which belies the truth but which will only be discovered when it is too late to change anything. Furthermore, the physical loss of life is significant, with Iago ensuring that everything that is dear to Othello is destroyed, whether it be real (such as Desdemona) or intangible (such as his honor).
Even Cassio cannot escape losing his honor because of Iago. Cassio berates himself for ruining (losing) his own reputation. In Act II, scene iii, he realizes that he has disappointed Othello through his actions (which were incited by Iago) and which were out of character. He cannot regain Othello's trust and this drives the plot forward as Iago weakens Othello's resolve, making him easier to manipulate.
Othello therefore loses his friends, his honor, his wife and eventually his life. He has been misled by "honest Iago" into believing that he has the "ocular-proof" he demands if he is to believe that Desdemona has been unfaithful to him with Cassio. He thinks that the handkerchief is sufficient proof. Othello has lost the ability to think rationally when it comes to his jealousy and he feels duty-bound to kill Desdemona or "she'll betray more men" as he says in Act V.ii.6. Othello admits that loving Desdemona is both "so sweet" and "n'er so fatal" (20).
Othello loses his credibility, his reputation and the respect of others to the point that, just before his death, he begs that his contribution to Venice be recognized despite everything. He would hate for others to think that he is nothing more than "a malignant and a turbaned Turk" as he says in Act V, scene ii. Iago has rendered Othello powerless and Othello suggests that he is "an honorable murderer" (298) and that "...I have done the state some service and they know't...Speak of me as I am...one that loved not wisely..." (342-347).