" The Bible's "it's better to give than receive" was not the raving of a lunatic. It goes back to a recurring theme that I've found in almost all my experiments: behaviour shapes your thoughts. My brain sees me giving a gift to Julie. My brain concludes I must really love her. I love her all the more. Which means I'm happier in my relationship, if a bit poorer. "

― A.J. Jacobs , The Guinea Pig Diaries: My Life as an Experiment