Why does Antonio enter into the potentially fatal loan contract with Shylock?
On the surface, Antonio's willingness to borrow money from Shylock is an act of altruism. With his capital embodied in ventures abroad, Antonio can only help his friend and kinsman Bassanio by assuming a loan. Antonio is a "good" (Christian) man, but as we look deeper into the circumstances, both the nature of his favor to Bassanio and his dealings with Shylock raise questions. To begin, Bassanio is a spendthrift who has not repaid money he has borrowed in the past, a fact that he freely acknowledges by saying "That which I owe is lost" (I, i.). Moreover, the reason that Bassanio needs money is to finance his journey to Belmont and acquire the accoutrements of a worthy suitor. In Shakespeare's day and our own, heiress hunting is hardly an admirable pursuit. Second, Antonio displays a certain pride in the management of his financial affairs, asserting that he can sleep well in spite of the risks entailed in his investments because "my ventures are not in one bottom trusted" (I, i., l.42). This, of course, proves unsound. Third, Antonio knows Shylock, has cursed him and has refused to deal with him in the past. Nevertheless, it is to Shylock that Antonio turns. Near the outset of Act I, scene iii, Shylock acknowledges the bad blood between himself and Antonio and vows to catch him on the hip. But it is Antonio who encourages Shylock to impose the "pound of flesh" default clause, saying to the usurer, "But lend it rather to they enemy/Who if he break, thou may'st with better face/Exact the penalty" (I, iii, ll.135-137). What all of this suggests is that there is a certain hubris in Antonio's decision to deal with Shylock and that his acceptance of the moneylender's terms enables Antonio to show off.