In Part Two of Life of Pi by Yann Martel, Pi finds himself stranded on a lifeboat with a Bengal tiger named Richard Parker after their ship sinks. One key episode that reveals Pi's perceptions/reality is when Pi attempts to establish dominance over Richard Parker by using a whistle to train him to follow his commands.
The author uses various narrative techniques to reveal Pi's perceptions and reality. For example, Martel employs vivid imagery to create a sense of Pi's surroundings, such as the "intolerable heat and bitter cold" of the ocean and the "countless stars" that blanket the night sky. Through Pi's descriptions, we also get a sense of his emotional state as he struggles with fear and uncertainty.
Another technique Martel uses is the use of flashback to Pi's life before the shipwreck. By juxtaposing Pi's past experiences with his current situation, the author allows the reader to see how Pi's background informs his perception of the world. For instance, we learn that Pi was raised in a zoo and has a deep understanding and love for animals. This background influences his decision to try and train Richard Parker rather than simply viewing him as a dangerous predator.