Why was money a problem for Antonio?
Without some more specific information as to what part of the play this question is referring to, the answer could be drastically different. For example, based on the play's opening scene, a reader could argue that Antonio does not have any problems with money. In that opening scene Solarino and Solanio are trying to figure out why Antonio is so melancholy. They suggest it is because he stands to lose a lot of money if the ships he is dealing with sink.
"I know AntonioIs sad to think upon his merchandise."
"Believe me, no. I thank my fortune for it—My ventures are not in one bottom trusted,Nor to one place, nor is my whole estateUpon the fortune of this present year.Therefore my merchandise makes me not sad."
I think a more abstract money problem that Antonio has is his cavalier attitude about it. He has a lot of money, and he freely lends it out. Not only does he lend it out, but Antonio also lends it out interest free. On one hand, this could be considered generous; however, if Antonio isn't taking enough precautions to cover himself, then his generosity is a problem for him.
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