Though Antonio and Shylock are pitted against each other, they still serve as foils for each other, defining each other by contrast and, in the end, commonality. The lenders come from different religions and approach their business differently: Antonio lends to his friends without interest, while Shylock makes a financial profit from usury. Each sees the other as a villain and both are correct, as Antonio and Shylock are both capable of cruelty. But in their antagonism and opposition—Antonio attacking Shylock in the streets, Shylock going to court to cut into Antonio’s flesh—each man proves something about the other, and about every man.
Although Antonio shows limitless generosity to his beloved Bassanio, his exchanges with Shylock prove that he is not simply a good Christian. When Shylock points out his cruelty, Antonio declares that “I am as like to call thee [dog] again, / To spet on thee again, to spurn thee, too." He wears his animosity like a badge of honor, proving himself far less than he purports to be. But Shylock is also guilty of what he chastises Antonio for: he acknowledges his own mistreatment and yet goes on to say “the villainy you teach me I will execute.” The similarities between the men—though they believe they have nothing in common—show how Merchant is acutely aware of the universality of hate. As Portia (disguised as Balthazar) asks, “Which is the merchant here? And which the Jew?” She speaks for all the characters, as it turns out they are not so easily distinguished, but are more like two men with different goals who ended up on the same path.