Why does Iago hate the Moor? That has always been the great question in Othello and one for which Shakespeare provides no definitive answer. Yes, he feels slighted when Othello promotes Cassio over him but is that enough reason to plot the general’s demise? Is it because he believes that Othello has slept with his wife, or because of the color of his skin? Or are Iago’s actions fueled by something deeper like self-loathing?
Shakespeare purposely doesn’t answer the question because he is more interested in prompting the audience to draw its own conclusions. The ambiguity is essential to the play although productions will at times highlight one line of reasoning over another in an attempt to give Iago clearer motivation. But that decision robs the play of its mystery and limits the unsettling horror of what happens on stage. More