Appearance vs. reality
Relevant to Iago's character; for although he is called "honest" by almost everyone in the play, he is treacherous, deceitful, and manipulative. Also applies to Desdemona, as Othello believes that she is deceitful and impure, although she is really blameless and innocent. Throughout history there has been a general understanding that appearances can be deceiving. Characters use this manipulative tactic to deceive others into believing things that are not true, in order to obtain their desires. the theme of appearance versus reality emerges in the play as Iago who is manipulating appearances works to deceive Othello who has difficulty distinguishing between what seems to be true and what really is true. The tragic plot of Othello hinges on the ability of the villain, Iago, to mislead other characters, particularly Roderigo and Othello by encouraging them to misinterpret what they see. Othello is susceptible to Iago’s ploys because he himself is so honest and straight forward. In this play Shakespeare plays with the idea of unreliable reality in a number of ways. They language of the play, which time and again refers to dreams, trances, and vision, constantly highlight the way in which what seems to be real may actually be fake.
Race is an extremely important theme; it has a great amount of influence on how people regard Othello for those who distrust black people merely on looks never like Othello, like Iago. Race also determines how Othello perceives himself as a rough outsider, though he is nothing of the sort. Othello's race sets him apart, and makes him very self-conscious; it makes him work hard and look carefully after his reputation, so he is regarded as equal to the white people that surround him.
Especially important with regards to Othello; Othello is defensively proud of himself and his achievements, and especially proud of the honourable appearance he presents. The allegations of Desdemona's affair hurt his pride even more than they inflame his vanity and jealousy; he wants to appear powerful, accomplished, and moral at every possible instance, and when this is almost denied to him, his wounded pride becomes especially powerful.
Othello's lack of self-knowledge makes him easy prey for Iago. Once Iago inflames Othello's jealousy and gets the darker aspects of Othello's nature into action, there is nothing Othello can do to stop it, since he cannot even admit that he has these darker traits.
Although the word "honest" is usually used in an ironic way throughout the text, most characters in the play go through a crisis of learning who and