LitCharts assigns a color and icon to each theme in Life of Pi, which you can use to track the themes throughout the work.
Survival
Religion and Faith
Storytelling
Boundaries
Summary
Analysis
On some nights Pi thinks he sees light in the distance, and he sends up a flare, but nothing ever comes of it. He recognizes that the area he can see is only a five-mile circle, so he has little hope of being rescued in the vast Pacific. The flares always smell like cumin to Pi, and they make him dream of Pondicherry.
Pi puts all his hope into reaching land instead of looking for a ship. In the brain smells can be closely related to strong memories, so the flares (which smell of cumin, a spice often used in Indian food) conjure up Pi’s childhood at Pondicherry.