Othello: Cassio vs. Iago

Othello's two most influential comrades, Cassio and Iago, are very different from one another.  Cassio is obviously a man of good character.  He is respectful and polite and gives his commander, Othello, the utmost respect.  Iago, on the other hand, is malicious and rude.  He is manipulative of everyone for his own selfish purposes, and while he is not unctuously trying to promote his disguise of an honest reputation, he is mean and rude to everyone.  For example, because he has no reason in particular to impress his wife because she has nothing that he wished to attain, he is incredibly inconsiderate to her. He tells Cassio, "In faith, too much. I find it still, when I have leave to sleep. Marry, before your ladyship, I grant, She puts her tongue a little in her heart And chides with thinking."  In this passage Iago is criticizing his wife for essentially talking to much.  This is how he greeted her.  Cassio on the contrary greets Emilia with, "Good ancient, you are welcome.—Welcome, mistress. (kisses EMILIA) Let it not gall your patience, good Iago, That I extend my manners. 'Tis my breeding That gives me this bold show of courtesy."  Clearly Cassio is the man of better character, though he may not be the man of better wit.