1. Man vs. Society
Throughout Twain's narrative, Huck and Jim both find themselves at odds with the "sivilizing" of the society in which they live. On the raft, Jim and Huck are equals, the world seems less complicated, and there is a logic to what occurs and what happens. Once they are on land, Jim must fear recapture and a return to slavery. Likewise, Huck has the fear of his abusive Pap, a reprobate to whom the court has awarded the care of Huck.
Sheburn's speech in Chapter XXII to the lynch mob accurately depicts Twain's view of society as conspiratorial and weakly corrupt:
"Do I know you? I know you clear through. I was born and raised in the South, and I've lived in the North; so I know....The average man's a coward....Why don't your juries hang murderers? Because thy're afraid the man's friends will shoot them in the back....If any lynching's going to be done, it will be done in the dark, Southern fashion....
Time and time again, Huck is confused by the behavior of adults and the illogical rules of society. Especially regarding his relationship with Jim, Huck is very confused. When it appears that Jim will be returned to slavery, Huck reasons that it would be better for Jim to be a slave where he formerly was. But, then, Miss Watson and others would be cruel to Jim for having been an ungrateful n*****.
The more I studied about this, the more my conscience went to grinding me, and the more wicked and low-down and ornery I got to feeling.
2. The Hypocrisy of Society
When Huck and Jim are on the raft, life is without conflicts and as they float downstream, Huck learns to view Jim as truly human and love him. In fact, early on, Huck is amazed that Jim cries and displays other human feelings. But, when they are ashore, Huck must pretend to think of slaves in a much different way.
Of course, the King and the Duke epitomize hypocrisy as they trick innocent and unsuspecting people, taking their money.
3. The Hypocrisy of Religion
Miss Watson repeatedly talks to Huck of sin and the Bible's teachings, yet she owns a slave. With great pangs of conscience in Chapter XXXI, Huck wonders if he should write to Miss Watson about Jim; however, he then worries about what people will say,
...if I was to ever see anybody from that town again, I'd be ready to get down and lick his boots for shame....The more I studied about this, the more my conscience went to grinding me, and the more wicked and low-down and ornery I got to feeling.
Huck says that he feels the "hand of Providence" slapping him and letting him know his wickedness in stealing a poor woman's slave. Nevertheless, because he is "playing double," Huck decides "All right, then, I'll go to hell."
In his innocence, Huck does not at first realize that slaves have feelings like himself. When, for instance, he witnesses Jim crying because he misses his family, Huck is genuinely shocked. After he is with Jim for long periods, Huck comes to love Jim and Jim becomes more of a father to him that his Pap has ever been.
When he thinks that he should write to Miss Watson, he has pangs of conscience, but after he writes the letter, Huck rebels against the culture, "All right, then, I'll go to hell...and never thought no more about reforming."
During his "odyssey" on the raft with Jim, Huck learns much about frienship, love, and charity from Jim, honesty, and ethics from the counterpoints of the King and the Duke. He certainly learns that it is wrong to lie.