d Othello, are military men; trained and accustomed to a society of rank, where a superior's judgment can determine the success or failure and/or death of his men, and who's judgement is taken at blind faith. As Othello's ensign, Iago is bound to accept and follow his commander's judgement, but by judging Cassio fitter for the job of Lieutenant than Iago, Othello has not taken into account what he has seen with his own eyes, 'Tis the curse of service;/ Preferment goes by letter and affection, Not by the old gradation, where each second/ Stood heir to the first." According to Iago, Othello has made a gross misjudgement that is reason enough for Iago's hate, "Now sir, be judge yourself/ Whether I in any just term am affin'd/ To love the Moor," and justifies Iago's resulting treachery that brings about his general's destruction.
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