Pi goes back to narrating. He imagines an atheist’s deathbed moments, and describes the atheist taking a final leap of faith. He then describes an agnostic clinging to his “dry, yeastless factuality,” trying to scientifically explain the white light he sees and missing “the better story.”
The phrases are immediately repeated to show their importance. The need to improve and order reality through storytelling (or religion) is a natural human instinct, and something similar even exists in animals – referring back to Pi’s explanation of the “fiction” the lions live with in accepting their trainer as their alpha.