The War on Crap Heuristics
Well, Lenin links to this piece of nonsense by Michael Rosen. First off, the conflicting ways of getting money in the play are not between finance and mercantile capital (which are basically the same thing anyway, both occuring in the sphere of circulation: financial capital being about the circulation of a special kind of commodity anyway, neitehr creates value, but merely transfers it from one place in the market to anotehr) but between trade and property. i.e. Antonio, who gets into his terrible scrape with Shylock is saved in the end by Bassiano marrying money - MARRIAGE is the sound way to wealth.
The division is between alienable wealth in commodities and inalienable wealth of privilige and aristocracy (hence why the happy ending comes about as part of discriminatory laws against Jews, rather than this dangerous equality before the law nonsense Shylock was exploiting).
Rosen is perhaps right in seeing Shakespeare identifying the mercantile class with Jewry - especially as, if I recall, Italian bankers were quite heavilly invested in England at that time. You play the game of merchandise, you have to deal with and become like these heathens.
It should be remembered that this play is supposed to be a comedy, and I have half an inkling that Shylock's powerful appeals for equality were meant to give rise to ironic howls of derrision, specifically when we compare how he is of the same Shakesperean pantomime villain mould as Iago et al in being bad for badness sake.
If it is a comedy, then we have a way out. Don't laugh. That is the power we mortals have over comedy, that destroys it's corrosive force, when Shylock is brought to heal by the majesty of state and law, feel sorry, don't luagh, bu remember, you're not not laughing with Shakespeare.