Several themes run quietly through the Adventures of Huckleberry Finn, a book often thought to be simply a carefree children's novel. Though the book may certainly be read on this level, it's also important to recognize Twain's less obvious motives for writing his epic American novel. Twain's introductory warning about the dangers of finding motives, morals, or plots in his novel ironically proves the existence of each.
The central theme, of course, is the constant struggle between freedom and slavery. This struggle exists for both Jim and Huck. Jim fears the physical slavery of the 1840's South while Huck fears the captivity of thought and behavior he so despises about Miss Watson and the Widow Douglas. He also, obviously, wants to escape the tyranny of his father. Both Jim and Huck turn to nature itself to escape the bondage of civilization. The raft enables them to find their escape from the barbarism of their society. The idea that Americans can find liberty by moving to the frontier was very real for those of Twain's generation. Often the American West proved to be a testing ground, not only for American individualism, but also for the pioneering ideas of equality and freedom.
More subtly, Twain indicts the American South for its phony romanticism and hypocritical Christianity. In Huck Finn , Twain suggests that the Christianity of the South is a living contradiction in that it accepts slavery yet ignores the Biblical notion of the equality of all believers. Though Twain often uses the "N-word" to reflect the realism of the times, a closer examination of the work as a whole, particularly the way in which he depicts Jim as a real person, proves that Twain was no racist, but actually an opponent of slavery.