In Act 2, Scene 2, Trinculo sees Caliban and perceives him like a monster. People in England would pay good money to see such a freak, says he. Then, when Stephano enters, he also notices Caliban's weird looks, and thinks that he would be a gift worthy of an emperor. Stephano gives him alcohol in order to tame him, reckoning that he would cost even more if he were tame.
Answer:
Valid evidence is based on facts or sound reasoning; invalid evidence is based on incorrect facts or faulty reasoning.
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Valid evidence is based on information that is closely related to the point being made; invalid evidence is based on contradictory or unconnected information.