Please consider the idea that Huck Finn is a terrific example of a defender
metaphysical morality!  The whole novel leads to the point where Huck must
make a decision about Jim.  He is "lobbied" by the notion that it would be
a "sin" to allow Jim to escape being returned to his  owners because that
would be equivalent to stealing property legally owned.  Huck was told that
he be damned if he let Jim go. One would think that this would be pretty
powerful stuff for a young fellow such as Huck. ( I never have known how
old he was supposed to be.}  But, even at his young age, he was able to
make the correct moral choice in the face of everything that he had been
taught, and say
I guess I will just have to go to hell and let Jim go.
I vote in favor of teaching this book to young people for this very reason.
By the way, I think that Ernest Hemingway may have had similar comments
about Huckleberry Finn, saying that the actual end of the novel was tha
point where Jim was let go.  The rest was a continuation of a "travelogue"
that was usually a part of many of Twain's writings because his audience
did enjoy his ability to take them to places that they would never go!