Love

From the book The Best of Success, compiled by Wynn Davis:

Love -  Love is the most important ingredient of success. Without it, your life echoes emptiness. With it, your life vibrates warmth and meaning. Even in hardship, love shines through. Therefore, search for love -- because if you don't have it, you're not really living -- only breathing.

"He has achieved success who has lived well, laughed often, and loved much."
   -  Bessie Stanley

"The moment you have in your heart this extra-ordinary thing called love and feel the depth, the delight, the ecstacy of it, you will discover that for you the world is transformed."
   -  J. Krishnamurti

"The cure for all the ills and wrongs, the cares, the sorrows, and the crimes of humanity, all lie in the one word 'love'. It is the divine vitality that everywhere produces and restores life."
   -  Lydia Maria Child