In at least one hundred words, how does mark twain use his characters to readers understand universal themes?

Twain investigates numerous American writing topics in his composition. Three subjects that show up much of the time all through the novel are opportunity, nature, and individual inner voice. Opportunity assumes a critical job in the story since Huck is attempting to free himself from Widow Douglas and his dad and Jim is getting away from servitude.  

One of the essential topics in Mark Twain's The Adventures of Huckleberry Finn is opportunity - and its absence. Jim is a slave who actually does not have his opportunity. He escapes so as to abstain from being sold down the stream, and he is urgent for his opportunity. The other significant topic in this novel is, obviously, race.

not concrete, existing in thought or as an idea but not having a physical or concrete existence

there purpose is to entertain