It is heartbreaking how much trouble Pi has killing his first flying fish. He cries. He compares himself to Cain. He wraps the fish in a blanket so he doesn't have to see it. But Pi changes drastically. In later chapters he drinks hawksbill blood, eats human flesh, and throws a shark to Richard Parker.

"You may be astonished that in such a short period of time I could go from weeping over the muffled killing of a flying fish to gleefully bludgeoning to death a dorado. I could explain it by arguing that profiting from a pitiful flying fish's navigational mistake made me shy and sorrowful, while the excitement of actively capturing a great dorado made me sanguinary and self-assured. But in point of fact the explanation lies elsewhere. It is simple and brutal: a person can get used to anything, even killing."