The basis of tragedy is man's helplessness against disease, war and death; the basis of comedy is man's helplessness against vanity (the vanity of love, greed, lust, power).
Bio: George David Wald was an American scientist who was best known for his work with pigments in the retina. He won a share of the 1967 Nobel Prize in Physiology or Medicine with Haldan Keffer Hartline and Ragnar Granit.