Jon Michael "Mike" Dunn was born in Fort Wayne, Indiana in 1941 and was raised there before his family relocated to Lafayette, Indiana during his teenage years. Dunn showed an early passion for engineering and science, and throughout high school he worked in various labs for the Purdue University Department of Biological Sciences.

In 1959, Dunn, a first-generation college student, matriculated at Oberlin College in Ohio. While he began his college career intending to become a molecular biologist, he became captivated by his coursework in philosophy and, more specifically, logic. He completed a senior honors thesis on logical behaviorism and graduated from Oberlin in 1963. Dunn then attended University of Pittsburgh (Pitt) for graduate school. At Pitt, he formed relationships with logicians and philosophers with whom he would collaborate throughout his career—most notably Nuel Belnap, Alan Ross Anderson, and Robert "Bob" K. Meyer. Dunn's doctoral research catalyzed a lifelong interest in relevance logics and algebraic approaches. He completed his dissertation, The Algebra of Intensional Logics, and earned his Ph.D. in Philosophy (Logic) in 1966.

Upon completing his Ph.D., Dunn accepted a job offer from the Philosophy Department at Wayne State University. In 1968, he relocated from Detroit, Michigan to New Haven, Connecticut to take a visiting faculty position at Yale University. In 1969, Dunn returned to his home state as an associate professor in the Department of Philosophy at Indiana University, Bloomington (IUB). Dunn spent the rest of his career at IUB. He was initially joined by Bob Meyer and several colleagues from Wayne State, including Hector Castañeda and Nino Cocchiarella. Dunn pursued interdisciplinary and cross-departmental research in applications of logic, especially with the Department of Computer Science (established in 1971).

Dunn travelled to Australian National University on a Fulbright in 1975-1976. He would later return to the country in 1983 as a Faculty Visiting Scholar at University of Melbourne. Dunn described both experiences as "incredible environment[s] for doing relevance logic," as he was able to continue existing projects with colleagues like R.K. Meyer (who, by 1975, had left IU for Australia) and to form new research relationships with influential logicians like R. Routley. One of these relationships was with Michael McRobbie, who was graduate student at Australian National University during Dunn's 1975-1976 visit. The two remained close colleagues throughout their careers, and in 1996-1997 Dunn advocated for McRobbie's nomination as IU's first Vice President for Information Technology.

Dunn was promoted to full professor in the Department of Philosophy in 1976. From 1980-1984, he served as the department chairperson. During this time and throughout the 1980s, Dunn was involved with curriculum development efforts such as the founding of the Cognitive Science Program (established in 1989) and an interdepartmental undergraduate major in Philosophy and Computer Science (first offered in the 1989-1990 academic year). In 1989, he was named the Oscar Ewing Professor of Philosophy and was granted the additional title of Professor of Computer Science, College of Arts and Sciences.

Dunn's career at IUB bent towards administrative roles starting in the late 1980s. He started as Associate Dean for Planning in the College of Arts and Sciences in 1988. The title was modified to Executive Associate Dean for Academic Affairs in 1991; he completed the appointment in 1993. From 1994-1997 Dunn served a second term as chairperson for the Department of Philosophy. After this term, Dunn focused on efforts to establish a new School of Informatics within the university. In December 1999, Dunn was named the founding Dean of the School of Informatics. He remained in this role until his retirement in 2007.

Dunn married Sarah Jane "Sally" Dunn in 1964. They had two children together. After retiring, Dunn continued to research and write. He also served executive roles in several Bloomington-based community organizations, including presidential and vice-presidential terms for the Old Northeast Downtown Neighborhood Association. Dunn died on April 25, 2021.