George Wald first won a place in the spotlight as the recipient of a Nobel Prize for his discovery of the way in which hidden biochemical processes in the retinal pigments of the eye turn light energy into sight. Among Wald's important experiments were the effects of vitamin A on sight and the roles played by rod and cone cells in black and white and color vision. Outside the laboratory, his splendid lectures at Harvard to packed audiences of students generated great intellectual excitement. It was as a political activist during the turbulent 1960s, however, that Wald garnered further public recognition. Wald's personal belief in the unity of nature and the kinship among all living things was evidenced by the substantial roles he played in the scientific world as well as the political and cultural arena of the 1960s.

Wald's father, Isaac Wald, a tailor and later a...