painting by Kirsten Johnson, 2000

One of the first scientists to apply mathematical models to human behavior in applied settings, his seven-decade career — in academia, industrial and military research labs, as a private consultant, and as a globe-trotting lecturer and expert witness — contributed enormously to human well-being.   His work has advanced theoretical understanding in areas like mental workload, attention and visual sampling, eye movements, queuing theory, control theory and human error modeling, with applications ranging from the design of space vehicles (including the Mercury, Gemini, and Apollo projects), modeling of driver behavior, highway safety, pilot behavior, airplane cockpit design, medication errors and patient safety, nuclear power plant safety, and even electronic publishing.

One of the founders of the academic study of human error, he and his wife Ann Crichton-Harris established the field's first conference in the 1980s, bringing together key researchers in this growing area of importance.  He was the first to conceive and describe a fully-functional electronic journal, for which he was later awarded the KMDI Pioneer Award in 2008 by the University of Toronto.

A key figure in the issues of patient safety and medication errors, he founded the Institute for Safe Medication Practices in Canada, receiving an award from the ISMP in 2001. Prof Senders also introduced the Failure Mode and Effects Analysis (FMEA) technique into medication and medical safety through the American Institute for Safe Medical Practices (ISMP) in 1994. He was a much-sought-after expert witness in cases of human error in medicine, the Professor of Safety Science at the University of Miami Medical School, and the James March Professor-at-Large at the University of Vermont.

But a mere recitation of accomplishments does not do justice to the complex polymathic nature of the man.  When Senders was invited to join U of T's Department of Industrial Engineering in 1974, a meeting was called to discuss whether he should receive tenure.  One skeptic noted that not only did Senders only have a BA but was, at 55, very old for a tenured position, and asked "Just how productive is he likely to be?"  A colleague who knew him retorted, "Your only concern should be that he might run you all ragged."  Senders did eventually receive a Ph.D. in 1982, from Tilburg University in the Netherlands in recognition of previous work.

Born on February 26, 1920, to Russian immigrant parents in Cambridge, Massachusetts, John Senders was the youngest of five children in a family environment full of word games, books, scientific inquiry, and fierce competition.  As a child, he demonstrated signs of mathematical genius and anti-authoritarian leanings in equal proportions, excelling in academic tasks...but only if he really felt like it.

Accepted as an undergraduate at Antioch College in 1936, he was sent home a year later for his refusal to take a required first-year math course, saying, "I've known this stuff since I was seven, and I'll be damned if I'll do it again."  In expelling him, Antioch's administration made an exception to its famously lenient policies, and thereby established a pattern which obtained throughout his long and singular career: as his father said to him on that occasion, "They will always make an exception for you.“

And, as friends, students, colleagues, and family can attest, he was a gourmet cook and an expansive host, a man who considered the surprise arrival of thirty dinner guests not as an imposition, but as an amusing and welcome challenge.  A raconteur with a vast repertoire, he astonished listeners not just with humorous anecdotes and tales from his career and travels, but with a ceaseless proliferation of new insights and ideas.  A "systems theorist" before the term came into public consciousness, he invariably found unusual and effective approaches to standard problems and situations.

He is survived by his wife, Ann Crichton-Harris, of Toronto, by his first wife, Virginia Loftus Senders, of Amherst, Massachusetts, and by five children and nine grandchildren.