Love
A theme in a literary work is a recurring, unifying subject or idea, a motif that allows us to understand more deeply the character and their world. In Othello, the major themes reflect the values and the motivations of the characters.
In Othello, love is a force that overcomes large obstacles and is tripped up by small ones. It is eternal, yet derailable. It provides Othello with intensity but not direction and gives Desdemona access to his heart but not his mind.
Othello takes Desdemona to Cyprus, the ancient dwelling place of Aphrodite, the Greek goddess of love. But Othello's Cyprus is fortified and dedicated to war, and love has lost its supremacy. Othello believes he is now devoted to love, but by consistently putting war first, he has slighted Aphrodite, and so, although he is victorious in battle, he is defeated in love.
Othello finds that love in marriage needs time to build trust, and his enemy works too quickly for him to take that time. The immediate attraction between the couple works on passion, and Desdemona builds on that passion a steadfast devotion whose speed and strength Othello cannot equal. Yet even his secret enemy, Iago, sees his constant and noble nature and judges that he will "prove to Desdemona a most dear husband." Hating Othello, Iago sets out to prevent that happening.
Iago often falsely professes love in friendship for Roderigo and Cassio and betrays them both. Desdemona's love in friendship for Cassio is real but is misinterpreted by the jealous Othello as adulterous love. The true love in friendship was Emilia's for Desdemona, shown when she stood up to witness for the honor of her dead mistress, against Iago, her lying husband, and was killed for it.
Iago uses the word "love" in a wider and falser manner than the other characters. He tells Roderigo he loves him at moments when he is deceiving him, getting at his money, or persuading him to a course of action from which Iago, not Roderigo, will benefit. Iago tells Othello he loves him at moments when he is whispering the cruelest words into his ear. Iago even says he loves Desdemona, meaning he could feel some sexual desire for her. Iago cannot say "love" honestly: For Iago, love is leverage.
Prejudice/Jealousy
Iago's scheme would not have worked without the underlying atmosphere of racial prejudice in Venetian society, a prejudice of which both Desdemona and Othello are very aware. Shakespeare's Desdemona copes with prejudice by denying it access to her own life: Her relationship with Othello is one of love, and she is deliberately loyal only to that.
Othello, however, is not aware how deeply prejudice has penetrated into his own personality. This absorbed prejudice undermines him with thoughts akin to "I am not attractive," "I am not worthy of Desdemona," "It cannot be true that she really loves me," and "If she loves me, then there must be something wrong with her." These thoughts, inflamed by Iago's hints and lies, prevent Othello from discussing his concerns and fears directly with Desdemona, and so he acts on panicked assumption. In order to survive the combined onslaught of internalized prejudice and the directed venom of Iago, Othello would have had to be near perfect in strength and self-knowledge, and that is not a fair demand for anyone.
Jealousy is what appears to destroy Othello. It is the emotion suggested to him by Iago, when he says, "O beware jealousy; / It is the green ey'd monster, which doth mock / That meat it feeds on" (III.3, 169–170). Iago thinks he knows jealousy, having rehearsed it in his relationship with Emilia to the extent that Emilia believes jealousy is part of the personality of men, but Iago's jealousy is a poor, weak thing compared to the storm of jealousy he stirs up in Othello.
Iago has noticed Othello's tendency to insecurity and overreaction, but not even Iago imagined Othello would go as far into jealousy as he did. Jealousy focuses Othello's mind so tightly on one idea, the idea that Desdemona has betrayed him with Cassio, that no other assurance or explanation can penetrate. Such an obsession eclipses Othello's reason, his common sense, and his respect for justice.
Up to the moment he kills Desdemona, Othello's growing jealousy maddens him past the recall of reason. Upon seeing that she was innocent and that he killed her unjustly, Othello recovers. He can again see his life in proportion and grieve at the terrible thing he has done. Once again, he speaks with calm rationality, judging and condemning and finally executing himself.
Appearance/Reality
Appearance and reality are important aspects in Othello. For Othello, seeing is believing, and proof of the truth is visual. To "prove" something is to investigate it to the point where its true nature is revealed. Othello demands of Iago "Villain, be sure thou prove my love a whore, be sure of it, give me the ocular proof" (III.3, 365–366).
What Iago gives him instead is imaginary pictures of Cassio and Desdemona to feed his jealousy. As Othello loses control of his mind, these pictures dominate his thoughts. He looks at Desdemona's whiteness and is swept up in the traditional symbolism of white for purity and black for evil. Whenever he is in doubt, that symbolism returns to haunt him, and despite his experience, he cannot help but believe it.
The significance of red is love, red strawberries like red hearts on the love token handkerchief, and like the red stains from Othello and Desdemona's first night of love on the marriage sheets. Such red on white is private and dear to the heart of Othello, and he expects it to be similarly dear to his wife. It is the belief that Desdemona gave away his handkerchief that drives him to kill her.
Honesty, Falseness, Christian Values
All the characters in Othello work within a context of background assumptions of traditional Christian values, which center on the concepts of honesty and sexual morality. In the world of Othello, an honest person is straightforward and reliable, tells the truth when it is appropriate to speak, and keeps silent on occasion. Honesty involves keeping one's word about what one will do or say and remaining constant to one's loyalties. An honest person is reliable in social and business matters, is a loyal friend, and can be trusted to keep a secret. Furthermore, an honest person is assumed to be reliable in terms of sexual morality. Sexual morality involves fidelity in marriage and abstinence outside marriage. Human nature being as it is, such an ideal is not always reached, and there is wide room in Shakespeare's society, thought, and language for adultery, prostitution, and impulsive words and actions later regretted.
The opposite of "honest," meaning either "reliable" or "sexually correct," is "false," with its connotations of counterfeit, unreliable, bad, and rotten. Sexually correct behavior is "chaste," incorrect behavior is "unchaste." Othello kills Desdemona because he thinks she is false, and Iago kills Emilia because she is honest.
In the world of Othello, these values are upheld as the basis for acceptable social interaction, and although the play is built around values founded in Christianity, there is very little religious awareness and concern in the dialogue, the exception being in the murder scene, where Othello proposes giving Desdemona time to pray for forgiveness of her sins before she dies. Desdemona, however, is far more concerned with talking Othello out of killing her and says only a very general "Lord have mercy on me." Iago never shows any concern for the values he abuses, but treats his life as a matter for cunning, maneuvering within his immediate environment only.
