2. “It cannot be/ long that Desdemona should continue her
 love to the Moor,” 1.3.339 – 1.3.340

“These Moors are changeable in
 their wills” 1.3.344 

3. This shows that Iago is also a character with racist beliefs. He uses the fact that Othello is a black man to convince Roderigo that a young attractive woman like Desdemona will not stay with him for a long time. He also justifies his argument by stating that black people are often moody and inconsistent in their desires. 

2. "The wealthy curled darlings of our nation,
 Would ever have, to incur a general mock,
 Run from her guardage to the sooty bosom
 Of such a thing as thou, to fear, not to delight.” 1.2.70 – 1.2.73

3. This demonstrates Brabantio’s racist attitude towards Othello. He believes that it would be impossible for a woman as beautiful as her daughter to be in love with a black man, therefore, accuses Othello to have used black magic on her. 

2.      “'I have already chose my officer.'
 And what was he?
 Forsooth, a great arithmetician,” (1.1.18 – 1.1.20)

"As masterly as he: mere prattle, without practise,
Is all his soldiership. But he, sir, had the election:
And I, of whom his eyes had seen the proof
At Rhodes, at Cyprus and on other grounds
Christian and heathen, must be be-lee'd and calm'd
By debitor and creditor:"
(1.1.27 - 1.1.32)

3.      Iago is jealous towards Cassio. He feels as if he had been betrayed by his own friend, who's fought by his side for years. He thinks he deserves the job more than him, since he’s a better swordfighter, and doesn’t understand why he did not get the promotion. His jealousy is the source of his anger towards Othello.

2.      “For that I do suspect the lusty Moor
 Hath leap'd into my seat; the thought whereof
 Doth, like a poisonous mineral, gnaw my inwards;” (2.1.289 – 2.1.291)

3.      This quote proves that jealousy is Iago’s main motivation. He’s awfully jealous that his wife would dare to have sexual encounter with any other men. He feels as if he had been betrayed by his wife, and by Othello, who gave his promotion to someone else, which builds up his anger. This intense feeling is what troubles him and pushes him to manipulate everyone around him. 

2.       “O, I have lost my / reputation! I have lost the immortal part of myself, and /
what remains is bestial. My reputation, Iago, /my 
reputation! » (Shakespeare, 2.3.250 - 2.3.253)

 This quote demonstrates how important a reputation is to someone, especially if they are a man. Cassio even affirms that it’s the most important, truest part of himself. He’d rather lose anything but his honour because people tend to make decision based on others’ reputation. Cassio feels deeply ashamed to be drunk and fighting another man when he’s known to be calm and collected. 

2.      “Though I do hate him as I do hell-pains./
 Yet, for necessity of present life,/
 I must show out a flag and sign of love,” (1.1.157 – 1.1.159)

3.      This quote illustrates Iago’s inconsistency in the way he acts around different people. Whenever Othello’s around, he always acts as if he was a noble and honest man, yet he gives him a stab in the back by informing Brabantio about the secret wedding. He manipulates Othello, and most of the characters, into thinking that he’s a good man willing to help, but in truth, he does everything selfishly to get whatever he wants.

2. “And nothing can or shall content my soul
 Till I am even'd with him, wife for wife,
 Or failing so, yet that I put the Moor
 At least into a jealousy so strong
 That judgment cannot cure.” (Shakespeare, 2.1.293 – 2.1.296)

3. Iago feels as if his ego had been attacked. His wife possibly having an affair is something to be shameful for. His manhood and honour are so attacked by this thought that he doesn’t even consider asking his wife about it. Getting revenge seems like the most manly thing to do and the only way to get his ego back up to normal is to make another man suffer.

2.      “Come on, come on; you are pictures out of doors,
 Bells in your parlors, wild-cats in your kitchens,
 Saints in your injuries, devils being offended,
 Players in your housewifery, and housewives' in your beds.” (Shakespeare, 2.1.118 – 2.1.121)

3.      This comment helps portray how misogynistic Iago is. He keeps demonstrating his hatred for women through insults and rude and sexist comments. He overgeneralizes them by asserting that they’re all loud and rude as soon as they’re not in public. He calls them out by saying that they’re untrustworthy and perverted, but in truth, he’s the one who constantly uses his loved ones.

Act 2, Scene 1: A Sea-port in Cyprus. An open place near the quay.
Act 2, Scene 2: A street.
Act 2, Scene 3: A hall in the castle.

Iago : “If she be fair and wise, fairness and wit,
 The one's for use, the other useth it.” (Shakespeare, 2.1.139 – 2.1.140)

Roderigo : "What a full fortune does the thicklips owe/
If he can carry't thus!" (1.1.68 - 1.1.69)

Iago to Brabantio : "Even now, now, very now, an old black ram/
Is topping your white ewe. Arise, arise;/
Awake the snorting citizens with the bell,/
Or else the devil will make a grandsire of you:" (1.1.90 - 1.1.93)

Brabantio to the Duke : "I therefore vouch again/ that with some mixtures powerful o'er the blood,/
Or with some dram conjured to this effect, /he wrought upon her." (1.3.105 - 1.3.108)

Desdemona to Brabantio : "I am hitherto your daughter: but here's my husband, /And so much duty as my mother show'd /To you, preferring you before her father,/
So much I challenge that I may profess / due to the Moor my lord." (1.3.185 - 1.3.189)