In Rome, Posthumus tells Philario he is sure of Imogen's honor, but has less confidence that he will win over the King. He is leaving it to time. In his exiled state, he regrets he cannot repay Philario for his generosity. But Philario says that Posthumus's goodness and company are payment enough. Besides, he is confident that Lucius, Augustus Caesar's ambassador, will by now have extracted the tribute arrears that he went to collect from Cymbeline. If Cymbeline does not pay up, he will face a Roman invasion.
Posthumus believes that Cymbeline will not pay and that there will be war. He points out that the Britons are more skilled in war than they were in Julius Caesar's day, when the Roman invaders defeated them.
Iachimo enters, commends Imogen's beauty to Posthumus, and gives him letters from her. Posthumus asks Iachimo whether his diamond still sparkles as brightly, or is dimmed by Imogen's betrayal. Iachimo replies that he has won the ring, for he enjoyed a night with the "easy" Imogen. Posthumus, reluctant to believe Iachimo, warns him not to joke about his losing the bet, and reminds him that they shall not remain friends. Iachimo answers that they will remain friends, since he has defeated Imogen's honor and not wronged her or Posthumus-both were willing participants.
Posthumus asks for proof that he has "tasted her in bed" (line 57). Iachimo describes the furnishings of Imogen's bedroom, the carvings over the fireplace, and even the fire-irons, but Posthumus says he could have heard this from someone else.
Finally, Iachimo shows Posthumus Imogen's bracelet that he stole from her as she slept. He says it matches the diamond, so both must be his. He claims that Imogen gave it to him, saying "she priz'd it once" (line 104). Posthumus suggests that maybe she took it off to send it to him, but Iachimo asks if she says that in her letter, which, of course, she does not.
Posthumus now believes Iachimo. He takes off his ring, which he says has become a basilisk to his eye (a basilisk was a mythical reptile whose glance was thought to be fatal). He rails against the falseness of women underneath their outward beauty, and the worthlessness of their vows.
Philario counsels him to be patient and take back his ring, as there is no proof that Imogen is unfaithful. It could be that she lost the bracelet, or that one of her ladies stole it.
Posthumus agrees, and asks for his ring back from Iachimo. He now wants Iachimo to cite some distinguishing feature on Imogen's body as proof. Iachimo swears by Jupiter that he had it from her arm, which again convinces Posthumus that his wife is unfaithful. He is sure she would not lose it, and her ladies are honorable. Posthumus is once more convinced that she has been unfaithful, and gives the ring back to Iachimo. Philario warns him again that the evidence is not strong enough to convince. But Iachimo describes the mole under Imogen's breast, which he says he kissed. Posthumus says that this "stain" confirms another-on her character-"as big as hell can hold" (line 140).
Posthumus erupts in fury and threatens to tear Imogen limb from limb in front of her father. Philario and Iachimo follow him out to prevent him from harming himself.
Posthumus re-enters and delivers a soliloquy against women. He regrets that men need them at all, and says all men are bastards: even he does not know where his father was when he was conceived. His mother seemed chaste, but then so does his wife. He attributes all vices in men to the feminine aspect or "woman's part" (line 174): lying, deceiving, ambition, and so on. Even to vice, he says, they are not constant, but ever changing.
Posthumus uses the imagery of the seasons in his hope that the King will be won over to his marriage. Now, he quakes in the wintry cold of the King's displeasure, but wishes for warmer days (lines 5-6).
Having failed to persuade Imogen to betray her marriage to Posthumus, Iachimo attempts to persuade Posthumus to betray Imogen, by believing that she is faithless.
Once again, Iachimo chooses his words for maximum emotional impact. He describes the hangings in Imogen's room as telling the story of Antony and Cleopatra (line 70). Just as Antony was Cleopatra's Roman, hints Iachimo, so was he Imogen's.
Posthumus's surrender to Iachimo's slanders is marked by his sudden inability to distinguish between appearance and reality. He believes that he is at last seeing the truth when he paints Imogen as being outwardly beautiful but inwardly deceitful. In fact, we know that she is beautiful both inside and out, as was Posthumus prior to his corruption by Iachimo. Posthumus's vision has become delusional.
There is a contrast between Posthumus's delusion and Cymbeline's. Posthumus's wife is honest but he thinks her false; and Cymbeline's wife is deceitful but he chooses to assume that she is honest. Imogen is the only major character who sees everyone as they are. Yet she suffers cruelly as the victim of others' delusions and dishonesty.
While Posthumus is undoubtedly a victim of Iachimo's evil, it is clear that he is also a flawed character whose one weakness-an insecurity over his wife's fidelity-is exploited. It is ironic that he is more ready to believe in the incorruptible honor of Imogen's ladies (line 125) than in that of his wife.
Posthumus takes on board Iachimo's imagery of hell (Act 2, scene 3, line 50) when he refers to Imogen's mole being a stain "as big as hell can hold" (Act 2, scene 4, line 140). His final soliloquy against women is as shocking as it is unjust, and must strain the audience's sympathy with him.