Alexander L. Pugh III (Jack) died February 7, 2025. Jack was raised in Philadelphia and Bala Cynwyd, Pennsylvania. He attended the University of Pennsylvania, studying electrical engineering. His ROTC program led him to Hanscom Air Force Base, and he later settled in Middlesex County.
Jack’s love of the nascent field of computer science led him to two master’s degrees in electrical engineering at MIT (SMEE, EE), where he collaborated with professor Jay Forrester.
With Jay and others, he developed System Dynamics, a field of research and practice for understanding dynamic, emergent patterns in our social, ecological, business, and political worlds. He and his wife, Julia, initiated and led the System Dynamics Society for almost 20 years. An entrepreneur in the 1960s, he developed the system dynamics software Dynamo, while co-founding with MIT professor Edward Roberts the management consulting firm Pugh-Roberts Associates (now Sage Analysis Group). He worked there until his retirement in 1995.
Jack met Julia (née Spear), in the MIT Choral Society, and they married in 1962. Jack is predeceased by his parents, aunts, uncles, and brother Walter Pugh. He leaves behind his wife; children Rebecca, Katrina, and Alexander, and their partners Laurie, Peter, and Anneliese; and grandchildren Isaiah (Jessica), Josiah, Sarah, Phoebe, and Benji.
Jack loved sailing, reading, fixing things, and hiking. After he retired, he was on the board of the Lincoln Public Library, the treasurer and webmaster of the First Parish Church of Lincoln, and the captain of his sailboat, the “Mobjack,” in which he won races over many years.
Memorial services will be held at 2 p.m., Saturday, May 10, in Duvall Chapel at Newbury Court, 80 Deaconess Road, and in Friendship, Maine, in July.
In lieu of flowers, please send cards or consider a donation to the Midcoast Conservancy in Maine, midcoastconservancy.org, P.O. Box 439, Edgecomb, ME, 04556.
Arrangements are entrusted to Dee Funeral Home & Cremation Service of Concord. To share a memory or to offer a condolence on Jack’s tribute page, visit DeeFuneralHome.com.
