Bardfilm and I are currently having a heated debate about sympathy for Caliban. He basically commits one sin (attempts to, at least), and for that he is cast out from his adopted family and turned into their slave, treated like something less than human.
His sin, for those unfamiliar with the story, is that Prospero walked on him trying to "violate the honor" of his daughter Miranda. Rape her, to put it bluntly.
Wait wait wait, don't get out your pitchforks yet, it's more complicated than that.
While recounting the story, Caliban tells us that he wanted to "people the isle with Calibans." So presumably he understood what he was trying to do, and that Miranda had to be old enough to do it with. That suggests that maybe ten years or so have gone by, making Miranda maybe twelve or thirteen, but making Caliban closer to twenty.
We can also assume that this was a single incident. Miranda clearly wasn't a willing participant, so it's not like she had any urges of her own that she was exploring behind her father's back.
So then we arrive at the critical moment. What do you think of Caliban's state of mind at that point? What was his capacity for understanding right from wrong? He certainly understood the general idea behind sex and the purpose of it, probably from having seen animals on the island. Do you think that Prospero ever sat down to tell him about the birds and the bees? I don't. I expect that the thought never occurred to Prospero until he literally walked in on them. Why would he? He taught Caliban language so that Caliban could tell him about the island, not to better Caliban's existence.
The other important part of the story, not to be too graphic about it, is that we don't really know what he walked in on. Was Caliban chasing her around the cave with a lusty look? Or did he have her on the ground and half out of her clothes? Prospero is the very definition of an overprotective father, so it's easy to imagine Caliban doing little more than giving her the eye and Prospero seeing that as over the line.
Whatever happened, it was enough to cast him out as a slave. I suppose it could be worse, I suppose Prospero could have just killed him outright. But then who would bring them their firewood?
The play is about forgiveness. Prospero brings his enemies to his island to forgive them. Do you think he forgives Caliban? Would you?