Nathaniel McLean Sage, Jr., was born in 1918 to Nathaniel McLean Sage and Charlotte (Simonds) Sage. He worked as a geologist and research administrator. Sage was a graduate of the Pomfret School, and completed his higher education at the Massachusetts Insitute of Technology (MIT), where he would receive a bachelor’s degree (1941), masters degree (1951), and PhD (1953) in geology. He worked as a professor of geology at Amherst College and the University of New Hampshire. From 1960 to 1968 he was associate director of the Division of Sponsored Research at MIT. He later became the director of research at the University of Rhode Island, where he stayed until he retired in 1983.