Beyond work and love, I would add two other ingredients that give meaning to life. First, to fulfill whatever talents we are born with. However blessed we are by fate with different abilities and strengths, we should try to develop them to the fullest, rather than allow them to atrophy and decay.... Second, we should try to leave the world a better place than when we entered it.
Parallel Worlds: A Journey Through Creation, Higher Dimensions, and the Future of the Cosmos (ed. Anchor, 2006) - ISBN: 9780307276988