How does Caliban reveal himself to be more eloquent than Stephano and Trinculo? What does this quality suggest about his character?

In scene 2, Caliban is still regarded as a "servant-monster," despite being revealed as a human. Stephano and Trinculo, though arguably less intelligent than Caliban, still treat him like he is hardly human because of his native status and skin color; and the fact that Caliban tolerates this treatment and name-calling shows that he accepts this inferiority and Stephano's tenuous authority as well. As characters' intelligence, nobility, and feelings become apparent through their language, Caliban's intelligence, though completely contradicted by his actions, is clear in the words he speaks to Trinculo and Stephano. At line 40, Caliban begins to speak in lines that approximate the rhythms of blank verse; and his speech, in lines 132-141, show a great descriptive power and poetic potential in this allegedly savage man. However, it must be noted that Ariel also appears right before line 40, and that means that Caliban could merely be voicing words that Prospero had already written for him.