foil: a character who, by his contrast with the main character(protagonist) or other character, serves to accentuate that character's distinctive qualities or characteristics is known as a foil.
Jim assumes a fatherly role to Huck at the end of chapter nine. Huck realizes that he also needs to take care of Jim, similar to the way he took care of his father. Jim is a foil to pap because Jim is caring, strong, and powerful,while pap is week and selfish. Both men are stubborn, though. Pap is stobborn because of acohal, Jim is stubborn because he wants to be in charge. Both men play an important role in Huck's life; pap shows that you don't always get what you want, while Jim shows that there is always someone there for you.
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