A great force of Nature, the Mississippi River cuts through the middle of the vast United States. It transports food and goods from the Northern states down to New Orleans, Louisiana. From there many a product is exported as well as imported to make its voyage north. Thus, the river possesses a life of its own; it is apart from society. While Huck and Jim are on the raft, traveling down the river, they are suspended from the rules of man and commune with Nature, instead. After escaping the carnage of the battle between the Grangerfords and the Shepherdsons, Huck lies with relief upon the raft,
I was powerful glad to get away from the feuds, and so was Jim to get away from the swamp...We said there warn't no home like a raft, after all. Other places do seem so cramped up and smothery, but a raft don't.
Out on the raft with only the open sky for a roof, Jim is a free man, and Huck is relieved of the "white man's burden" which dictates that he must treat Jim as property and an inferior creature. Instead, free of the restraints of society, Huck becomes aware that Jim is a man with emotions, a man who loves Huck as though he were his child, and a man with much common sense: "He had an uncommon level head, for a n****," Huck acknowledges. It is, indeed, the lessons of life learned upon the raft which floats on the life-giving river that teaches Huck true morality, a morality that leads Huck to refuse to turn Jim over to Miss Watson. "All right. I'll go to hell," Huck resolves his moral crisis, for he cannot subject Jim to the dehumanizing conditions of slavery.
Thus, the river represents freedom of body and soul. On the river there is freedom from the rules of society and its conflicts; on the river there is a clarity given to the conscience that is no longer tethered by the restrictions of man-made laws. Indeed, on the river rightful moral decisions can be made without the physical and civil the bindings of society's rules. On the river, Huck and Jim develop--to use the words of Mark Twain himself-- "sounder hearts."