The comic sub-plot has various uses for the play. It brings light relief&ndash without it, it would be a very dramatic play, if not boring.As because Prospero controls the whole island we know that nothing can really happen that he doesn&rsquot want to, so the play is lacking tension and the comic sub-plot prevents it from being a very boring play. Drunkness is amusing anyway, they fall about and say stupid things which is entertaining for us, plus this is Caliban's first drink and we recognise the feelings he expresses for this&lsquo celestial liquor&rsquo and makes it all the more funny. That Caliban sees these two fools as kings also makes it amusing&ndash&lsquo I prithee, be my God&rsquo asTrinculo says&lsquo A most ridiculous monster, to make a wonder of a poor drunkard!&rsquo. When he sees what they are later he is disgusted with himself&ndash&lsquo What a thrice-double ass Was I, to take this drunkard for a god, And worship this dull fool!&rsquo
As well as providing humour, this trust of Caliban&rsquos echoes hisformer trust for Prospero. He hasn&rsquot learned from when Prospero turned on him, his naïvety shows through his trust and adoration of the wine. Through the&lsquo aside&rsquo comments of Trinculo and Stephano we know they are using and teasing him. Its in this situation we feel almost sorry for Caliban, this&lsquo abhorred slave&rsquo, this&lsquo demi-devil&rsquo is still very trusting and doesn&rsquot he have reason to hate Prospero? He is an animal, with animal instincts and cannot be trained otherwise. Though Prospero is understandably angry that he tried&lsquo to violate the honour&rsquo of Miranda, but he is overly harsh with him. The sub-plot shows us how Caliban is trusting yet again, and we can see how affectionate he would have been to Prospero when he first arrived on the island, and how understandably bitter he would be when his master turned on him. This is an echo of the