As Huck Finn fools the perceptions of those around him, he leaves them with a false perception of reality: the perception that he wanted them to perceive.
Fitzgerald presents a character with the same ability in The Great Gatsby: Jay Gatsby, the titular character himself. Gatsby's past is a mystery for the majority of the novel. The narrator, Nick Carraway pursues Gatsby's history, only to be lied to. Even the reader is knocked off of the right path; the novel has multiple, yet all equally convincing, depictions of Gatsby's past. Most of these depictions are told by Gatsby himself, making them that much more convincing. By the end of the novel, only a few characters actually learn of Gatsby's true origins. Even then, this is only when he tells them directly. This is because Jay Gatsby is shrouded with an aura of mystery that only falls when he allows it to. There could be an even deeper story shrouding Gatsby, one that is not revealed by his untimely demise. This is because, for characters like Jay Gatsby and Huck Finn, reality is only as they present it to be. Just like a magician, the truth of the situation is only as these clever people want you to believe.
While some people can manipulate the perceptions of those around them, most do not have this talent. They must obediently follow the flow of the river of reality, as they have no control over the stimuli around them. Jim, Huck's black companion on the Mississippi River, is of this category. He is a slave at the start of Clemens' novel: both to his white owner and to his crushing reality. Jim is black in a time period where it was better to be anything but black. Because of this, Huck and Jim have vastly disparate realities. Huck can weasel his way out of a situation, whereas Jim cannot, "because if he set [sic] up, people could tell he was a nigger a good ways off." [Chapter 9, Clemens] In this way, he is never truly free from his reality, even after his escapades on the river.