“I have a story that will make you believe in God.” (authors note, VIII)
This is an important quote as it introduces one of the key themes in Life of Pi, the purpose of religious storytelling. The author is saying that through a story he will prove you the no just the character but to the reader that god exists, not necessarily in the form commonly believed, but belief in something.
"But I don't insist. I don't mean to defend zoos. Close them all down if you want (and let us hope that what wildlife remains can survive in what is left of the natural world). I know zoos are no longer in people's good graces. Religion faces the same problem. Certain illusions about freedom plague them both." (pg. 21)
Here Pi is comparing zoos to religion, just like zoo's that confine animals in cages, religion is now seen to bind people. However, in nature animals are bound too, they cant go around as they please in fear of being killed by a predator or human interference ruining there habitat. Pi is saying just as zoos protect animals from the dangers they do now know, religion, and by default god, protects man from the unknown afterlife.
"I'll be honest about it. It is not atheists who get stuck in my craw, but agnostics. Doubt is useful for a while. We must all pass through the garden of Gethsemane. If Christ played with doubt, so must we. If Christ spent an anguished night in prayer, if He burst out from the Cross, "My God, my God, why have you forsaken me?" then surely we are also permitted to doubt. But we must move on. To choose doubt as a philosophy of life is akin to choosing immobility as a means of transportation." (pg. 31)
This further proves that god is not being proven in the conventional way because here Pi says atheist do not bother him because they believe in something. It is Agnostics that bother him Secunia they choose not to pick a side. Proving that Pi is trying to make the reader choose what to believe, whether it be god or no god, and stop being on the fence.
"And what of my extended family – birds, beasts, and reptiles? They too have drowned. Every single thing I value in life has been destroyed. And I am allowed no explanation? I am to suffer hell without any account from heaven? In that case, what is the purpose of reason, Richard Parker?" (pg. 108)
This shows how completely Pi's life has been erased, not only are his parents gone but all the animals he grew up with have also drowned. He is truly left alone in the world.
"So tell me, since it makes no factual difference to you and you can't prove the question either way, which story do you prefer?" (pg. 352)
By asking this question the reader is forced to either choose God or Atheism. If you prefer the story with the animals you choose to be an Atheist and only believe what is in front of you or factually provable. If you prefer the story with the animal the you choose to believe in what may be possible and inexplicable but there is no way to disprove it either, God.