Carl S. Keener was a member of the Department of Biology at The Pennsylvania State University from which he retired after serving 31 years in 1997 as Professor Emeritus. His undergraduate degree is from Eastern Mennonite University and his graduate degrees are from the University of Pennsylvania (M.S.) and North Carolina State University (Ph.D.). His professional career has been in systematic botany, with a particular specialty in the Ranunculaceae (Buttercup Family), the flora of Pennsylvania, and the mid-Appalachian shale barren endemic flora. Long-time interests include process theology, Mennonite history and thought, history and philosophy of science, and ethics.