As wicked dew as e’er my mother brushed
With raven’s feature from unwholesome fen
Drop on you both! A southwest blow on ye
And blister you all o’er! (I.ii.)

Caliban’s first words in the play express his deep hatred for Prospero and Miranda. He curses them in two ways here. First he references the witchcraft of his mother, Sycorax, calling for her “wicked dew” to drop on them. Then he references the southwesterly winds, which were humid and thought to carry disease. Here, Caliban may be implying a kind of venereal disease that would cover his masters in painful blisters.

All the charms
Of Sycorax—toads, beetles, bats—light on you,
For I am all the subjects that you have,
Which was first mine own king. And here you sty me
In this hard rock, whiles you do keep from me
The rest o’ the island. (I.ii.)

Once again, Caliban calls on the wicked charms of his mother, Sycorax, in order to curse his captors. In these lines from Act I, Caliban also indicates the source of his hatred for Prospero and Miranda. Prior to their arrival he had been his “own king.” But they have since taken his power and agency away, confining him to one small corner of the island. Caliban’s use of the phrase “sty me / In this hard rock” suggests that he may even be imprisoned in some kind of cave. Caliban also retaliates against Prospero when he claims that he is “all the subjects that you have.” This claim is cutting, since it implies that Prospero has less power than he imagines.

You taught me language, and my profit on ’t
Is I know how to curse. The red plague rid you
For learning me your language! (I.ii.)

Caliban spits out these angry words in response to Miranda’s self-satisfied claim in Act I that as a “savage,” he should be grateful for the education she gave him. Caliban implies that he has, in fact, gained nothing of real value from this education. Given that he has been stripped of all meaningful agency, the only thing he can do with his captors’ language is express just how much he despises them.

I’ll show thee the best springs. I’ll pluck thee berries.
I’ll fish for thee and get thee wood enough.
A plague upon the tyrant that I serve!
I’ll bear him no more sticks, but follow thee,
Thou wondrous man. (II.ii.)

In these lines from Act II, Caliban curses Prospero and pledges his allegiance to Stephano. Caliban’s evident gullibility lends this scene a deep sense of irony. When he mistakes the two bumbling drunkards, Stephano and Trinculo, for gods, Caliban effectively repeats the mistake he originally made with Prospero. Just as Caliban offered to show Prospero around the island when he first arrived, he now makes the same offer to these strangers. And just as he ended up Prospero’s slave, it seems obvious that Caliban will receive equally cruel treatment under the rule of Stephano, who insists on Caliban being a hideous monster.

Be not afeard. This isle is full of noises,
Sounds and sweet airs that give delight and hurt not.
Sometimes a thousand twangling instruments
Will hum about mine ears, and sometime voices
That, if I then had waked after long sleep,
Will make me sleep again; and then, in dreaming,
The clouds methought would open and show riches
Ready to drop upon me, that when I waked
I cried to dream again. (III.ii.)

Caliban, a longtime inhabitant of the island, understands that the island’s ever-present illusions are ultimately harmless. He says as much to Stephano and Trinculo, declaring, “This isle is full of noises, / Sounds and sweet airs that give delight and hurt not” (III.ii.). That said, even though the island’s illusions do not pose a physical threat, they are certainly manipulative on a psychological level. Caliban indicates that he prefers the comforts of sleep to the challenges of waking life. That he would prefer to spend his days dreaming may indicate just how powerless he feels under Prospero’s command.