What is the theme in One: A Novel by Richard Bach?

One of the most important themes of the book is that of learning. Both Richard and Leslie view life and their experiences in spacetime as a learning experience. They explore themselves and what could have been in alternate lives as they travel through spacetime. At times when Richard wants to quit, Leslie wants to continue of to see what else they can learn. When they find themselves outside a tent in a desert, Leslie enters the tent because she knows that there is something to be learned there. Learning expands one's horizons and Leslie is the adventurous one that wants to continue the exploration in spacetime.