Fundamental Themes in The Merchant of Venice

While there are many fundamental themes in The Merchant of Venice, only one seems to drive the play to its inevitable conclusion. There is a constant theme of self interest versus love. On the surface, this seems to be the dividing factor between the Christians and the Jew, as Shylock is supposed to only care about money, profits, and such, while the rest of the cast value human relationships more.
Men such as Antonio and Bassiano lend money without interest or even thought at times, and end up taking far more risks for those they care about. “He lends out money gratis, and brings down | The rate of usance here with us in Venice.”(1.3.45) Shylock complains to the audience in an aside. Antonio agrees to Shylock’s nasty terms simply because he loves Bassiano that much.
Further on in the play, Shylock reportedly runs through the streets crying “'My daughter! O my ducats!” (2.8.15). Through this statement he seems to value his money at least as much as his daughter and th...