If it’s the same one, or any one that belongs to her, then together with the other evidence it’s pretty strong. (III.iii.448-449)
Oh, I’d kill that bastard Cassio forty thousand times if I could! Killing him once is not enough revenge. Now I see it’s true. Oh, Iago, all the love I felt is gone, vanished in the wind. Welcome, hatred and vengeance! Get out of my heart, love! My heart feels like it’s full of poisonous snakes! (III.iii.450-458)
I could, sir. But i don't want to now. This is just a trick to take my mind off what I'm asking you for. Please hire Cassio again. (III.iv.83-85)
Bring me the handkerchief-- My mind is full of doubt. (III.iv.86)
This Iago is extremely honest and good, and he knows a lot about human behavior. If it turns out that she really is running around on me, I’ll send her away, even though it’ll break my heart. Maybe because I’m black, and I don’t have nice manners like courtiers do, or because I’m getting old—but that’s not much—She’s gone, and I’ve been cheated on. I have no choice but to hate her. Oh what a curse marriage is! We think our beautiful wives belong to us, but their desires are free! I’d rather be a toad in a moldy basement than to have only a part of someone I love, sharing the rest of her with others. This is the plague of important men—our wives betray us more than those of poor men. It’s our destiny, like death. We are destined to be betrayed when we are born. Oh, here she comes.
The conflict that is portrayed above is an external person vs. person conflict. Iago is manipulating Othello into thinking that Desdemona cheated on him by providing proof of how Cassio was "using" the handkerchief that Othello gave Desdemona as a first keepsake. This then makes Othello furious and trust Iago. This scene impacts the drama because it shows that now Iago is in control of everything that happens to Othello and Desdemona's relationship since Othello is 100% sure he is telling the truth and thinks that Desdemona is an unloyal "whore" who walks around sleeping with men.
This is an external person vs. person conflict. After hearing Iago's proof and thoughts on Desdemona, Othello needed to see it for himself so he went and asked Desdemona to show him the handkerchief. When Desdemona started asking him questions on why it was necessary at this moment he got angry because for him the handkerchief symbolized their love and without it it meant that their love will fall apart. As they started arguing Othello was screaming at her telling her to show him the handkerchief while Desdemona was talking about Cassio and how Othello should hire him back as his lieutenant which worsened the situation because Othello already thinks that Desdemona is cheating on him with Cassio but now that she can't stop talking about him and is trying to help him makes it seem that Iago is telling the truth and Desdemona is a liar. This scene impacts the tragedy because this scene was when Othello was going to prove it for himself whether or not Desdemona was cheating on him, however, Desdemona failed to shows him otherwise which led him to finally distrusting Desdemona.
The conflict portrayed in Othello's monologue is an internal, person vs. self conflict. As one can see he is doubting Desdemona and other wives of their loyalty to their husbands based on what Iago has shown him. Othello also doubts himself stating that the reason Desdemona might have cheated on him might be because of his skin color or his age. This monologue, therefore, illustrates how he is completely brainwashed and does not see that Desdemona is an innocent, loyal wife, and Iago is the bad guy. This scene impacts the play because it shows how he feels about Iago and Desdemona which foreshadows the way he might act with these characters and the situation they are in.