Symbols are objects, characters, figures, or colors used to represent abstract ideas or concepts.
As the seat of greed, corruption, and decadence, at least according to the prevailing prejudices, Venice was the beneficiary of years of stereotype in English drama. Italians in general were seen as sensuous, decadent beings, thanks to their extremely sophisticated culture, history of Machiavellian politicians (Lorenzo de Medici, Cesare Borgia, Machiavelli himself) and beautiful (and often erotic) love poetry. Though not things considered particularly awful today, this type of decadence made English people wary of being infected with immorality, and Venetians were seen as the worst of the bunch. The direct influence of the "power of Venice" to corrupt can best be seen in the Sir Politic Would-be subplot, where the English knight Sir Politic "goes Venetian" and becomes a lying would-be thief. But the Venetian setting probably made the story more believable for most English audiences, signifying the fascination of the play with disguise and deceit, though also, perhaps against Jonson's intentions, distancing them from the play's moral message, by placing the greed in a historic far away place traditionally associated with greed, instead of right in the heart of London.
There is a "fable" running throughout the play, through the associations the characters' names create with animals. It is very simple and tells the tale of a cunning "Fox" (Volpone in Italian), circled by a mischievous "Fly" ( Mosca in Italian), who helps the Fox trick several carrion-birds—a vulture (Voltore), a crow (Corvino) and a raven (Corbaccio) into losing their feathers (their wealth). The animal imagery emphasizes the theme of "parasitism" in the play, where one life form feeds off of another. And it should also be remembered that fables are tales with simple moral messages, told for a didactic purpose. Though much more complex, Volpone, at its heart shares the same purpose, making the use of "fable-like" symbolism appropriate and helpful in understanding the meaning of the play.