All the masterpieces of art contain both light and shadow. A happy life is not one filled with only sunshine, but one which uses both light and shadow to produce beauty.
What a piece of work is a man! how noble in reason! how infinite in faculties! in form and moving how express and admirable! in action how like an angel! in apprehension how like a god! the beauty of the world! the paragon of animals! (Hamlet, act II, scene 2)