In the Argument, Jonson summarizes the main conflict of the play in the form of an acrostic poem. (An acrostic is a poem in which the first letter of each line spells a word; in this case, the poem spells "Volpone.") Volpone, a miser who is close to no one but his servant Mosca, (referred to as "his Parasite") increases his wealth by pretending to be mortally ill, encouraging people to give him gifts in the hopes of becoming his heir. Mosca, however, plays these would-be heirs against each other ("weaves / Other cross-plots") until Volpone's scheme is nearly exposed by two informers. Volpone and Mosca then conspire to discredit these informers ("New tricks for safety are sought") to prevent their scheme from coming to light. In the end, Volpone and Mosca turn against each other and lead each other into ruin ("all are sold").
The Prologue expresses Jonson's hope that the play will be both entertaining and enlightening. Jonson claims that this is his greatest skill. Jonson responds to critics who accuse him of writing too slowly by boasting that he wrote Volpone in only five weeks and without the help of anyone (e.g., coadjutor, journeyman, novice, tutor). He then informs the audience that there is no slapstick in his play, but only refined comedy appropriate to his higher purpose. He points out that he observes the Classical laws of time, place, and persons. Finally, he informs the audience that they will laugh until they are red-faced and refreshed.
In the Argument, the two main characters of the play are first introduced. Volpone, which means "fox" in Italian, and Mosca, which means "fly" in Italian, are both appropriately named in keeping with the theme of Animalization. Right away, the reader or viewer is alerted to the characters' status as allegorical, which invites us to consider the play as much as a fable as an entertainment. This suits Jonson's stated moral intention.
The very existence of the Argument also reinforces this moral intention. Jonson describes the main action of the play before we see it; thus nothing that follows should come as much of a surprise. The Argument transforms a first reading (or viewing) of the play into a second reading. That is, we are freed from sorting out what is happening so that we can concentrate on why it is happening. This is Jonson's hope - as articulated in the Prologue: that his audience will focus on the moral lessons of the play, the "why," rather than simply on the plot, the "what."
As in the Epistle, Jonson's boasts in the Prologue can, for the most part, be interpreted as jabs at Shakespeare. When he brags that he wrote Volpone without the help of anyone, Jonson is attempting to set himself apart from Shakespeare, whose later works are believed to have been written with the help of an apprentice. Likewise, Jonson makes a point to say that he does not employ slapstick in his play, thus setting him apart from Shakespeare, who was known to make use of vulgar humor (e.g., sexual innuendo) as well as slapstick in his efforts to appeal to the groundlings (the lower-class audience members who could only afford to stand on the ground in front of the stage).
To conclude the Prologue, Jonson notes that he observes the laws of time, place, and persons. Here he is referring to the Classical Unities, three dramatic conventions which derive from Aristotle's Poetics. They are the unity of time, - the play's action begins and ends within 24 hours - the unity of place, - the play's action occurs in a single setting or a reasonably confined area - and the unity of action - the play's action centers around one main conflict or plotline. In Volpone, the title character's rise and fall take place during a single day in which he sees "clients" in the morning and stands trial in the late afternoon or evening. Although the courthouse, Volpone's house, and the streets are all designated as settings for different scenes, Volpone's action takes place exclusively within the city limits of Venice. Finally, the main conflict of Volpone, as summarized in the Argument, is the deceptive way in which Volpone makes his fortune. It is unclear why Jonson chose to call this last unity the "law of persons."
Whereas Jonson adhered strictly to Aristotle's Unities, Shakespeare took much greater liberty with them. In The Winter's Tale, for example, the passage of sixteen years is artificially introduced by a character named Father Time. In addition, the kingdoms of Sicilia and Bohemia, separated by several days' travel at sea, both represent settings of The Winter's Tale. While Jonson saw Aristotle's Unities as laws, Shakespeare saw them more as guidelines, to be bent or broken at the playwright's discretion.