Having said this, the genre that Ben Jonson's The Alchemist is analyzed under is that of farce. Critics consider that his characters, which are similar to the types in Chaucer's The Canterbury Tales, are farcical rather than allegorical. Jonson is using farce, with a whole catalog of "typical" characters, to mock the social element of swindlers and victims, a prevalent aspect of Jacobean society. "Typical" characters are those drawn from established literary types as opposed to fully realized individual characters. In farce (as in fable and allegory) this technique works rather well because audience members are familiar with these established literary types and can therefore all the more easily understand and appreciate the farce set before them, indeed, they may have on occasion been one of those types (e.g., victim or swindler) themselves.
In considering The Alchemist, it is important to note that as a critic and analyst, the reader may choose to read The Alchemist as an allegory if allegorical representations strike your perception of the story. Furthermore, a work of prose or poetry may be in whole an allegory or in part an allegory or have isolated passages or lines that are allegorical. Dr. Wheeler elaborates on this point more fully. When a reader gives an analysis or critical opinion of a work not typically considered allegory (e.g., The Alchemist) as being allegorical in whole, in part or even in one sentence, this sort of allegorical reading is called allegoresis. So in summary,