In "Life of Pi" by Yann Martel, the main need that he is asserting that human beings need is the need for imagination and storytelling. The entire story itself was an incredibly imaginative sequence of events that created a highly engaging and interesting story. This theme of storytelling, and of humans enjoying a good story is prevalent throughout the book. In the first section, little Pi is drawn to 3 different religions, because each one of those religions had such great stories behind them. The stories appealed to him, so he accepted all religions. Then, at the end of the book when his Japanese inquisitors ask him which story was the real story, the one with animals or the one without, Pi only asks, simply,
"Which is the better story, the story with animals of the story without animals?"
The men both agree, "The story with the animals." Pi seems to be saying here that if that is the best story, go with it. Let it be. And, that storytelling is an amazing source of strength, escape and relief to people.
I hope that helps a bit; that is just one lesson that can be found in this book, and the quote that goes with it. Good luck!