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Benson Mates

Professor of Philosophy, Emeritus

UC Berkeley

1919 – 2009



Benson Mates, professor emeritus of philosophy, died in Berkeley on May 14, 2009. He was an important and widely respected member of the University of California, Berkeley, faculty from 1948 until his retirement in 1989, after which he continued to teach occasional courses or seminars in philosophy. He had a strong influence across the whole campus through his attentive service over the years on a number of important committees.


He was a member of the Committee on Budget and Interdepartmental Relations in the 1960s and 1970s, and the Executive Committee of the College of Letters and Science in the 1970s. In addition, he served on the College of Letters and Science Committee on the Academic Program, the College of Letters and Science Committee on Committees, and the Academic Senate’s Committee on Library. He was one of the founding members, and at different times one or another administrative officer, of the Group in Logic and the Methodology of Science. Within the Department of Philosophy he served on all the major committees over the years and was chair of the department from 1975 to 1977.


Benson was born in Portland, Oregon on May 19, 1919, and studied philosophy and mathematics as an undergraduate at the University of Oregon, receiving the B.A. in 1941. His graduate study in philosophy at Cornell University was interrupted by the Second World War, in which he served in the U. S. Navy in Portland. After the war he switched to Berkeley and began graduate study here in 1945, concentrating primarily on Greek philosophy and mathematical logic. These interests were combined in his Ph.D. thesis on “The Logic of the Old Stoa,” which was completed in 1948.


That work, subsequently revised and published as Stoic Logic (1953), was a groundbreaking achievement, both in classics and in the history of logic. It was one of the first works to open the way for serious study and proper appreciation of the Stoics as philosophers and logicians. Greater sophistication in mathematical logic made it possible for Benson to demonstrate clearly for the first time the intricate ways in which the logical ideas of the Stoics were well in advance of those of Aristotle and in many respects closer to our own. The book remains a landmark in both fields. Benson’s interests in both classics and logic helped forge links between the philosophy department and the Department of Classics on the one hand, and the Department of Mathematics on the other that have remained a distinctive feature of the study of philosophy at Berkeley for decades.


In 1965, Benson published Elementary Logic, which was quickly appreciated as one of the clearest, most accurate, and most reliable of all the many textbooks in mathematical logic. It is still widely used, and praised, and not simply as a textbook. Its presentation and explanation of fundamental distinctions, and the methods it draws on and develops, are relied on and defended in the investigation of substantive logical and philosophical questions in different fields.


Perhaps because of his own natural cast of mind, Benson also had a lifelong fascination with the skeptics of antiquity, opponents of the Stoics. It was not only a question of the past. He was very sympathetic to what appears to be the legacy of ancient skeptical ways of thinking in present-day epistemology and metaphysics. This found expression in his Sceptical Essays, published in 1981, in which he defended his own “skeptical” responses to the present-day philosophical problems of our knowledge of the external world and of the freedom of the will. The problems were shown to be deeper and more resistant to either solution or dissolution than the mainstream of current philosophy had supposed.


Since the 1950s, Benson had been pondering and even studying in manuscript form the difficult philosophy of Leibniz. This came to fruition in 1986 in his The Philosophy of Leibniz, a massive scholarly and interpretative work exploring the logical foundations of Leibniz’s idiosyncratic and often strange metaphysical doctrines. Deep problems of identity and necessity are clarified and illuminated, notwithstanding Benson’s unwavering view that, soberly considered, most of the metaphysical doctrines themselves are “cognitively meaningless.”


In later years Benson returned to the study of ancient skepticism, and in 1996, after his retirement, he published The Skeptic Way, an English translation, with masterly introduction and commentary, of the book in which most of what is known or believed about ancient skepticism has come down to us, Sextus Empiricus’s Outlines of Pyrrhonism.


Benson was a careful, patient thinker with a great respect for learning and for clarity and rigor. He was acutely sensitive to intellectual pretentiousness in any form, and suspicious of its presence not only in philosophy but in whatever he saw to be merely new and trendy. He was a somewhat self-effacing man of modest demeanor, shrewd intellect, and high achievement. Benson made lasting contributions to philosophy, the history of philosophy, the history of logic, and the understanding of antiquity. His work was of the highest order: clear, precise, illuminating, thoroughly reliable, and always at the highest level of logical and philological expertise. He would never himself have said what is true: that this University, and scores of outstanding students and colleagues over the years, are appreciative beneficiaries of his teaching, his learning, and his embodiment of the highest intellectual standards.


Benson was married to Lois Onthank Mates, who died June 1, 2009, after a long illness. Benson and Lois are survived by their five children, John, Maureen, Margaret, Susan, and Ellen, and seven grandchildren, Anton, Ben, Chelsea, Sophie, Debbie, Rebecca, and Will.



              Barry Stroud                                                                                                                2009

              Hans Sluga