Prejudice and Intolerance
The Venetians in The Merchant of Venice almost uniformly express extreme intolerance of Shylock and the other Jews in Venice. In fact, the exclusion of these "others" seems to be a fundamental part of the social bonds that cement the Venetian Christians together. How otherwise would the ridiculous clown Launcelot ingratiate himself with the suave Bassanio? Or why would the sensitive Antonio tolerate someone as crass as Gratiano? It is possible to argue that Shakespeare himself shares his characters' certainty that the Jews are naturally malicious and inferior to Christians because of Shylock's ultimate refusal to show any mercy at all and, as a result, his pitiful end.
Yet there are also reasons to think that Shakespeare may be subtly criticizing the prejudices of his characters. Shylock's fury comes not from some malicious "Jewishness" but as a result of years of abuse. For example, though he is criticized by Antonio for practicing usury (charging interest on borrowed money) Jews were actually barred from most other professions. In other words, the Christians basically forced Shylock to work in a profession that the Christians then condemned as immoral. Shylock insists that he "learned" his hatred from the Christians, and it is Shylock alone who argues that all of the characters are the same, in terms of biology and under the law. Viewed this way, The Merchant of Venice offers a critique of the same prejudices that it seemingly endorses?
Human and Animal
Closely related to the theme of prejudice and intolerance is the theme of humanity—and the inhumanity of which various characters accuse one another. In insulting and abusing Shylock, the Venetians frequently denigrate him as an animal or devil. Shylock, in turn, seeks to reduce his debtor Antonio to the status of an animal whose body can be bought or sold. In the courtroom scene, he justifies his purchasing of a pound of Antonio's flesh as being fundamentally similar to the way in which other Venetians might buy slaves or livestock.
Shakespeare was writing The Merchant of Venice as a philosophical movement called "Renaissance humanism" became prominent. This philosophy defined humans as exceptional beings, existing outside of the chain of being of God's other creatures. Yet, The Merchant of Venice shows how this type of humanism can be used to abuse outsiders. After all, if being "human" ceases to be based on biology, then exactly who is human and who isn't becomes a matter of interpretation. The play's Christian characters clearly believe that being Christian is a primary requirement for being human, as both the insults aimed at Shylock and the Prince of Morocco suggest. In his famous speech justifying his desire for revenge in 3.1, Shylock explicitly rejects the humanist definition of "humanity," describing his similarity to the Venetians in terms of biological functions that all human beings share: tickling, eating, bleeding, dying. Constant references in the play to "flesh and blood" further highlight humans' biological, "animal" origins..
Law, Mercy, and Revenge
Both the central action of The Merchant of Venice—Shylock's attempt to revenge himself on the Christian Antonio—and the romantic subplot—between Bassanio and Portia—explore the relationship between law, mercy, and revenge.
Shakespeare's contemporary, the philosopher Francis Bacon, defined revenge as a "kind of wild justice." When one private individual decides to revenge himself on another, he is going outside the official justice system. And yet, as the phrase "wild justice" suggests, the revenger is responding to what he sees as a "higher law." The revenger takes the law into his own hands when he feels that the state is not capable of or refuses to enforce justice. Therefore, while law and revenge are technically opposed to each other, since revenge is illegal, they also overlap. Shylock, pursuing Antonio's "pound of flesh," exposes the intimate connection between law and revenge. He seeks vengeance against Antonio precisely by sticking to the letter of the law within the Venetian justice system.
In the courtroom scene of Act 4, scene 1, both the Duke and Portia present mercy as a better alternative to the pursuit of either law or revenge. Shylock explicitly refuses to show mercy, while the Christians, in sparing Shylock's life in the end, claim that they have. Yet, when they do, Shylock himself asks to be killed. He says that, having had all of his possessions confiscated and his religious identity revoked (which would also make it impossible for him to work as a money-lender, since Christians were not allowed to practice usury), he has nothing left to live for. The question of who is or is not merciful, therefore remains open.
Greed vs. Generosity
The primary grievance that Antonio has against Shylock is that he is greedy—for charging interest to those who borrow money from him when they are in need. The Venetians implicitly contrast Shylock's greed with the generosity that they show one another. For instance, Antonio is willing to place his whole "purse and person" at Bassanio's disposal and regularly saves other Christians from having to pay interest to Shylock by paying off their debts for them.
It seems that, like love or mercy, generosity is limitless, unbounded. However, The Merchant of Venice also frequently begs the question of whether friends aren't using friends, or lovers their lovers, for materialistic reasons. For instance, why is the perpetually indebted Bassanio so intent on wooing the rich Portia? And as Portia's and Nerissa's anger over the rings that their husbands give away in the final scene reflects, even the freest gift-giving comes with strings attached, like the rules governing Shylock's more frankly capitalistic contracts.
Reading and Interpretation
Instances of reading and interpretation occur many times in The Merchant of Venice. An early scene in which Shylock and Antonio bicker over the meaning of Biblical scripture shows that the all-important distinction between Jews and Christians basically boils down to interpretive differences—different ways of reading and understanding a shared heritage of texts.
The play also stages "scenes of interpretation"—in which the act of reading becomes a dramatic event. The first major instance, connected to the themes of both law and love, is when the Prince of Morocco becomes the first suitor to try to solve the riddle of the caskets, with major consequences for both Portia and himself depending on whether he interprets it correctly. This scenario repeats with both the Prince of Aragon and Bassanio. The courtroom scene, in which Portia must find an alternative way to read and understand the law in order to save Antonio's life, similarly turns an act of interpretation into a highly dramatic game with very high stakes. The Merchant of Venice shows how the practice of reading (and not just reading literature) is woven into the structures of prejudice and intolerance, love, law, and justice—how it is central to everyday life.
Love and Friendship
In connection with mercy and generosity, The Merchant of Venice also explores love and friendship between its characters. The central romantic relationship of the play is that between Bassanio and Portia. Their marriage is paralleled by several others: the elopement of Shylock's daughter, Jessica, with the Christian, Lorenzo; and the marriage of Portia's servant, Nerissa, to Bassanio's companion, Gratiano. In addition, numerous critics have suggested that the strongest friendship in the play—between Antonio and Bassanio—also approaches romantic love. In addition, the play shows how strong the amicable ties are that connect all the various Venetian characters.
Given the generosity that they motivate between characters, love and friendship might seem to offer alternatives to the ugly emotions of prejudice, greed, and revenge on display in The Merchant of Venice. However, beginning with Bassanio's borrowing money from his friend Antonio in order to woo Portia, the play also demonstrates that the apparent purity of love and friendship can be tainted by selfish economic concerns. In addition, love and friendship are also at the mercy of the law, as seen in Portia's being subject to the terms of her father's riddle of the caskets.