Iago's brazen assertions and Roderigo's timorous apologies for awakening Brabantio are finally effective. Brabantio comprehends what Iago and Roderigo are saying and, in fact, recalls a dream that foretold of just such a calamity. Dreams and omens of this sort are common in literature of this time and create the sense that fate somehow has a hand in the tragic events about to follow.
As Brabantio moves into action, calling for more lights and arousing members of his household, Iago steals away, but not before explaining his reasons for doing so: It must not be public knowledge that Iago himself is an enemy of Othello; if Iago's machinations are to be successful, he must outwardly "show out a flag and sign of love, / Which is indeed but sign" (157–158). Thus he will manage to stay in Othello's good graces. For this reason, he must go and rejoin his general.
In addition to this speech reminding us of Iago's dangerous, diabolical treachery, it also serves to inform us about Othello's significance to Venice. Othello is a superior public figure, one who will soon be summoned to end the Cyprian wars and a man upon whom the Venetian state depends for its safety. This fact is contained in Iago's comment that "another of his fathom they have none / To lead their business" (153–154). Othello is a man of high position, as well as one of high honor and one who is, therefore, worthy of being considered a tragic hero.
