Man vs. Self
Throughout the novel Pi is at a constant struggle with himself. He must decide what is more important to him, surviving or staying true to himself. To face this inner conflict with himself he creates a scapegoat to do what he cannot make himself do, that is Richard Parker. When he is forced to kill the chef in order to survive he forces himself to think that it is Richard Parker that does it and not him. Even though Pi is becoming Physically weak he refuses to become mentally weak as that would cause him to lose faith in God. This is because if he mentally stops believing he will survive he is subconsciously thinking God is not there.
Man vs. Society
Pi is forced to fight society at a very young age when he begins to practice multiple religions. He must practice at time when others wont see him because he is often harassed and kicked out of temples when the priests see him. He must face all this discrimination simply because he believes in more then one religion and that is not acceptable in the society in which he lives.
Man vs. Nature
When Pi leaves for Canada with his family and the Tsimtsum sinks Pi is left stranded at sea in a Life Boat. He must then face the harsh conditions at sea and fight against the elements in order to survive, he faces hunger, dehydration from the sun all while he is surrounded by an ocean full of fish. Ultimately nature takes everything from Pi including his family, and his family's fortune.