I think the Life of Pi is a metaphor. That the story which occurs at the end between Pi and his interrogators is a metaphor for religion.
I believe that this story has been used to explain to us how often we don’t believe a far fetched story, even if it is entirely plausible. I think that Yann Martel was trying to send us the exact same message about religion; just because you have little evidence, it doesn’t mean that it’s not possible.
In the book, Pi tells the Japanese interrogators (Mr. Chiba and Mr. Okamoto) everything that happened to him aboard the boat and the life raft. The entire book outlines this story, and all of the unlikely events that occurred, which kept Pi alive. Absurd events happened throughout his 227 day journey, all far-fetched, but true at the same time. Immediately, the interrogators do not believe him. Even though he knows (and we know, from reading the book) that all of these events are true, they refuse to believe what a small, Indian boy is trying to tell them. In order to help them believe, Pi tells a story similar to the last one, but more realistic in terms of the known and unknown. He replaces unlikely animal patterns with human actions. And so on.
Now, lets say that the first story, about the tiger, the orangutan, the acidic tree island, is true. This story represents religion. Impossibilities happen. Out of the ordinary relationships occur. Yet, no matter how far-fetched, they still happen. I believe that Yann Martel is telling us that religion is not often believed by people, no matter the power it has to impress us. People don’t see large amounts of concrete evidence that religion occurred, so they want an easier story to follow. One that follows the known, not the unknown. Such as the big bang theory. It’s considered to be possible, because it’s events follow our knowledge on particles. And so we believe unlikely events that we know about, rather than unlikely events that we don’t know about.