Raised in Rosedale, Miss., Mac died in Winchester, Tenn., June 22, 2022, at age 81.
Mac graduated from The University of the South (Sewanee) in 1962 and earned a Ph.D. in mathematics from Princeton in 1972. He returned to Sewanee, where he taught mathematics for 44 years.
An avid reader, writer, and conversationalist who found wisdom and beauty in words and numbers, Mac believed in the intrinsic good of an educated and curious life. He was a dedicated and principled teacher, intent on sharing the joy of mathematics with all his students, many of whom later became mathematicians.
Mac was determined to make calculus accessible, relatable, and intriguing, likening mathematical analysis to poetry, music, and other expressions of the human spirit. He published a textbook, Calculus: An Historical Approach, and a second edition, Calculus: A Liberal Art, to present mathematics as a bridge between the sciences and humanities. In 2006, he received the Distinguished Teaching Award from the Southeastern Section of the Mathematics Association of America.
He is survived by his wife of 49 years, Mary Patten Priestley; and his children, Bill, Thomas, and Patten Priestley Mahler. He was “Grandmac” to grandchildren Will, Julianna, Lily, and Lyell.
Graduate memorials are prepared by the APGA.