Retain a childlike sense of wonder. At a certain point in life, most of us quit puzzling over everyday phenomena. We might savor the beauty of a blue sky, but we no longer bother to wonder why it is that color. Leonardo did. So did Einstein, who wrote to another friend, “You and I never cease to stand like curious children before the great mystery into which we were born.”5 We should be careful to never outgrow our wonder years, or to let our children do so.