Antipholus of Syracuse is the younger half of a set of long-separated twins. He was raised with his father, Egeon, in Syracuse, and separated from his mother, Aemilia, and brother, Antipholus. S. Antipholus’s only traveling companion is his "bondsman," S. Dromio, a servant boy his father purchased to be his companion and attendant when both were newborn babies.
The conceit of the play rests on S. Antipholus’s decision to leave home. We learn from Egeon that as soon as S. Antipholus turned eighteen, he became "inquisitive" about his missing twin brother, and, along with S. Dromio, left his father to go find their respective other halves. S. Antipholus seems to have a wandering and inquisitive spirit. In addition to his wanderlust, he’s characterized by a grave loneliness. The first scene we meet S. Antipholus in he proclaims that he’ll go lose himself in the strange Ephesian city – which seems the habit of people that are used to being alone or anonymous. Then, S. Antipholus explains his loneliness to us almost immediately. He describes his lack of fulfillment when he says he feels like a drop of water that’s fallen into the ocean to look for one other drop of water. He feels alone without knowing his mother and brother, but he seems to seek them to form some part of his identity. He admits that in his search for them, he’s lost his own identity, but we also get the feeling the boy never really felt complete (or he might not have set out looking for his twin in the first place).
These traits are particularly interesting given S. Antipholus’s interaction with Luciana. He’s convinced that she’s unearthly, but rather than being wary or afraid of her, he pleads with her to teach him about himself. Just as he wanders geographically, he also wanders emotionally; it seems that in his love for Luciana he sees a chance to be grounded in a way that truly matters to him. It’s also important that he concedes that Luciana might herself be an enchantment. S. Antipholus’s explanation for much of the strangeness that occurs in Ephesus is magic. He’s willing to assume that explanation always lies outside of himself, either in dreams or in witches, because he has no true knowledge of himself.