[Mr. Okamoto:] "I'm sorry to say it so bluntly, we don't mean to hurt your feelings, but you don't really expect us to believe you, do you? Carnivorous trees? A fish-eating algae that produces fresh water? Tree-dwelling aquatic rodents? These things don't exist."
[Pi:] "Only because you've never seen them."
[Mr. Okamoto:] "That's right. We believe what we see." (3.99.47-9)
Some define madness as seeing things that don't exist. But Pi slyly questions this definition. Considering, especially, Pi's love for and obsession with God, it's a hop, skip and a jump to a defense of the Big Guy. It's possible Pi is asking Mr. Okamoto a super-secret hidden question: does the fact that most people don't see God mean God doesn't exist?