Act 4 Scene 4
Antipholus E. is still awaiting the money from Adriana which will buy him out of jail. Dromio E. enters, bringing the rope's end that his master had earlier asked for. He knows nothing about any money. Antipholus E. is furious and beats him. Adriana, Luciana, and the Courtesan enter, bringing Dr Pinch, a schoolmaster who has the reputation of a conjurer. Adriana has engaged Pinch to restore her husband (whom she believes to be mad) to his senses, presumably by exorcism. However, when Pinch tries to feel Antipholus E.'s pulse to diagnose his disease, Antipholus E. hits him. Pinch begins to try to conjure the devils out of Antipholus E, who silences him.
Antipholus E. contemptuously addresses his wife as if she were a prostitute, asking if those with her are her "customers". He asks whether the Courtesan dined at his house today. She replies that he himself dined at home, not knowing that this was the other Antipholus. Antipholus protests that he was locked out of his house, which Dromio E. confirms. Pinch concludes that both Antipholus E. and Dromio E. are mad, and that they must be tied up and laid in a dark room. Antipholus moves as if to attack Adriana (though not stated in the stage directions, this can be inferred from the reaction of the others), accusing her of conspiring with her companions to humiliate him. Frightened, she asks for him to be tied up. As Pinch's assistants try to bind him, he struggles, only confirming Pinch's theory that he is possessed by the devil. Adriana promises the Officer that she will pay off his debts. Pinch and his assistants carry off the bound Antipholus E. and Dromio E.
The Officer tells Adriana that her husband owes Angelo two hundred ducats for the gold chain. The Courtesan testifies that she saw Antipholus with the chain. But Adriana says he never received the chain and that she has not seen it. She asks the Officer to take her to Angelo so that she can ascertain the truth.
Antipholus S. and Dromio S. enter, frightened and with swords drawn. Luciana and Adriana think that they are Antipholus E. and Dromio E., escaped from capture, and they flee with the Officer. Antipholus S. tells Dromio S. that even witches are afraid of swords, and orders him to load their belongings on board ship so that they can leave.
Antipholus E. angrily asks his wife whether the Courtesan dined at his house today, and accuses her of being as much of a strumpet as the Courtesan. The irony is that Adriana was innocently entertaining his twin brother, whereas he was not-so-innocently dining with the Courtesan.
He loses our sympathy further in his violent attack on his wife. Though he is not mad for the reasons Adriana and Pinch believe, he has succumbed to a more dangerous form of madness - unwarranted jealousy.
The foolishness of Antipholus S.'s fear of magic, witches and sorcerers is demonstrated in the ludicrous character of Pinch, who is both a schoolmaster and a hobbyist conjurer. Pinch's incantations are absurd rather than sinister.
As we shall see again in the next act, in the character of the Abbess, Shakespeare mistrusted those who set themselves up to diagnose and 'cure' others, including quacks, mountebanks, purveyors of trite wisdom (such as Polonius in Hamlet), and physicians, and often satirized them. In particular, Thus Antipholus E.'s struggling against being bound confirms Pinch's ridiculous diagnosis of possession by the devil, yet if he did not struggle, he would still be bound. There is a strong sense that one cannot win against such self-appointed authorities, since everything one says is taken as confirmation of their prejudices.