Who hadst deserved more than a prison.
Caliban isn't seen as a man. Because of his different race native language, Miranda and Propero view him as an animal and that justifies their control over him as they lock him away in the cave because he doesn't even deserve a prison cell. It's really interesting how similar but different certain characters are veiwed as throughout Shakespeare's plays. For instance, Caliban reminds me of Othello not only because they're both colored and used for others' advantages, but because of how differentyl they're veiwed. Othello is seen as a noble man in a power position thst he has earned and is disliked by other characters becaue of that. While Caliban is viewed as an ungrateful orphaned slave who is essetially useless becaue of his back-talk to the people who "taught him eveyrthing." This doesn't necissarily mean the audience sees them as this but that's how they're supposed to be portrayed.