In Sir Philip Sidney's Defence of Poetry (1580), the author argues that poets have a responsibility to make learning more palatable through their art. Shakespeare fulfills Sidney's requirement by using his plays to explore complex ideas and issues, and thus, he makes learning more palatable for the audience. Prospero does the same thing when he uses his art to make Caliban's learning more palatable. Caliban is never harmed through Prospero's magic, and Prospero prevents Caliban from injuring anyone else. But Caliban does learn, through the use of Prospero's magic, that Trinculo and Stefano are not gods, nor are they honorable men who can be trusted. Trinculo and Stefano are really the dregs of society, useless opportunists, who think only of pleasure and greed. The ending of the play does not suggest their redemption. But the ending does suggest Caliban's. He is finally able to see Trinculo and Stefano for what they are, and he is able to reconcile with Prospero.
Rather than view the relationship between Prospero and Caliban as that of master and victim, consider instead that Prospero uses force to control Caliban not because he wants to dominate or enslave this natural man but because this is the traditional means to subdue a beast. Caliban's behavior is more closely aligned to the beast than to man, and thus, he must be controlled in a similar manner. By the play's conclusion, Prospero must forgive his enemies; this is, after all, a romantic comedy. But if Prospero is to fulfill Sidney's mandate, Caliban must also learn from his master how to be more human. His final speech (V.1, 298–301) indicates he has learned some valuable lessons.
