Answer:
Caliban does make a number of regretful decisions, after all. For example, he puts his trust in Stefano and makes a fool of himself with drink. He is also rather savage in devising his plot to kill Prospero (though no more savage than Prospero is in setting the hounds upon him).
Caliban attempts to further motivate Stephano to make the attack by telling him that when he has killed Prospero, he will have all Prospero's "brave utensils," that is, his splendid household goods.
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