Themes in "Life of Pi" include religion, spirituality, the will to live, man versus nature, suffering, death, psychological madness and fear, according to SparkNotes and Shmoop. Another theme is the importance of storytelling. The novel follows a teenager named "Pi," who loses his family to a shipwreck off the coast of Japan. He then survives on a lifeboat for weeks with a ferocious Bengal tiger.
Religion is a theme of the novel from the beginning when an old man tells a story that intends to "make you believe in God." Pi grows up studying various faiths, including Christianity, Islam and his native Hinduism. After he dabbles in several religions, the protagonist admires atheists the most.
The will to live is a theme that takes up the bulk of the plot. Pi survives on a lifeboat that originally contained the teenager, a Bengal tiger, a zebra, a hyena and an orangutan. The tiger eats every creature on the boat except Pi. The two remaining castaways survive together at sea for weeks until they reach land in western Mexico.
Psychological madness during the quest for survival reveals itself as a plot twist at the end of story. Pi recounts his ordeal to two Japanese men, who do not believe that there were animals on the boat. Instead, the protagonist says that the animals were actually humans. The orangutan is Pi's mother, the hyena is the irascible ship's cook, the zebra is a crewman and the Bengal tiger stands in for Pi. The Japanese men and the audience are left to decide to accept either the animal version or the human version of the story.