- 1926 – 2022
Horace Chandler (“Chan”) Davis (1926 – 2022) was a white mathematician, pacifist, human rights activist, science fiction writer, poet, musician, and educator who taught in the University of Toronto’s Department of Mathematics from 1962 until the mid-2000s.
As a scholar in the field of mathematics, Davis is best known for his work in the areas of operator theory and linear algebra, as one of the creators of the theory of fractal ‘dragon curves’, the eponymous Davis-Kahan theorem, Bhatia-Davis inequality and Davis-Kahan-Weinberger dilation theorem. His interdisciplinary work included publishing in areas such as ethnomathematics and ethnobiology, mathematics education, and ethics.
Embedded in many aspects of Davis’ life and work was his deep commitment to social justice and human rights. His advocacy to protect freedom of speech and academic freedom encompassed the release of political prisoners internationally; upholding gender and racial equity in academic environments and beyond; and promoting social responsibility in science. Within the context of UofT, he was active in Science for Peace, a leadership figure within a group of radical mathematicians, and campaigned against labour inequity on campus.
Professor Davis was born on August 12,1926 in Ithaca, New York. His parents, Horace “Hockey” Bancroft Davis and Marian Rubins Davis, were both economists and educators grounded by a deep-seated belief in socialism, racial equity, and labour rights. Their teaching brought the family to several universities and colleges across the United States, as well as in Brazil and Europe.
At the age of sixteen, Professor Davis was awarded a National Scholarship to Harvard, where he later received his Bachelor of Science in 1945, followed by an MA and PhD (under Garrett Birkhoff) in 1950. While at Harvard, he joined groups of science fiction writers and enthusiasts, the Astounding Science-Fiction Fanclub and the Boston Stranger Club, as well as The Futurists, who approached the genre from a Marxist perspective.
For a brief period in 1943, Davis joined the US Communist Party (CPUSA), later withdrawing as a requirement for his participation in the Navy Officer’s Training Program. The latter led to Davis’ work as a minesweeper for the US Navy in the spring of 1945. The following year he returned to Harvard for his graduate studies.
During this period, Davis expanded his participation in groups both political and creative: he re-joined the CPUSA, became a member of the Federation of American Scientists, a group of scientists who resisted the military use of nuclear energy, and the US’ left-wing Progressive Party. From his early publishing of the science-fiction fanzine “Blitherings”, Davis also began writing his own short-stories, publishing his first, “The Nightmare” in Astounding Science Fiction in 1946. Davis continued to write both science-fiction and essays on the genre until the 1970s, publishing sporadically later in his career.
At a meeting of the Young Progressives in 1948, Davis met the eminent social historian Natalie Zemon, then a student at Smith College, with whom he shared similar political values. In 1950, Davis accepted a faculty position at the University of Michigan, where the two, now married, relocated.
In 1954, Davis was summoned to testify before the House Un-American Activities Committee (HUAC), the McCarthy-era investigative committee known for its aggressive pursuit of individuals suspected of carrying communist sympathies. Davis declined to answer the Committee’s questions about his political affiliations citing his First Amendment right to free speech and assembly. This differed from many other individuals who invoked their Fifth Amendment right to protection against self-incrimination in refusing to answer questioning. Davis’ defiance, particularly through his attempt to challenge the constitutionality of the hearings , led to his indictment for contempt of Congress. Following the decision, Davis together with two colleagues, Mark Nickerson and Clement Markert, faced an investigation by the University of Michigan, and all were ultimately fired.
In 1957, Davis was convicted of contempt of Congress and through a number of appeals attempted to bring the case before the U.S. Supreme Court. By 1959, these efforts were exhausted and Davis was found guilty and sentenced to six months in prison.
In both the period after his dismissal from the University of Michigan and following his release from prison, Davis struggled to find employment as having been blacklisted by most American academic institutions. For a period, he served as Editor for the American Mathematical Society’s Mathematical Reviews (1958 – 1961). After his release from prison, he also began considering Canada, where other academics facing similar persecution had succeeded. He reached out to Donald Coxeter at UofT’s Department of Mathematics and in 1962 was hired by the University as Associate Professor. Zemon Davis also accepted a role at the University and the family relocated that year.
At the Department of Mathematics, Davis was known for his Monday afternoon operator theory seminars and the impact he had on his numerous students, as evidenced in Series 2.2: Alphabetical Correspondence. Over his career, Davis authored over 80 papers. Many of these focused on his primary mathematical interests: linear algebra and operator theory. However, his wide-ranging research including among other topics geometry, fractal ‘dragon curves’, and the philosophy of mathematics. He edited four books: Linear Algebra and Its Application(1977), Geometric Vein: The Coxeter Festschrift with Branko Grünbaum, Coxeter Legacy: Reflections and Projections with Erich W. Ellers (2006), Shape of Content: Creative Writing in Mathematics and Science with Marjorie Senechal and Jan Zwicky (2008).
Davis’ involvement in professional associations spanned the majority of his career. Three decades after his work with Mathematical Reviews, Davis took on the role of Editor-in-Chief for The Mathematical Intelligencer in 1991. Here he was celebrated for his expansive view of the mathematical community and its interests alongside his reputation as both a generous and rigorous editor. Davis also brought his deep social concern and principled approach to the mathematical community, and a broader scientific one, through his participation in the AMS’ Committee on Human Rights of Mathematicians, its precursor, the Mathematics Action Group, the Canadian Mathematical Association Committee on Human Rights, the Association for Women in Mathematics, Science for Peace, and Science for the People .
His activism similarly connected him to numerous other organizations and individuals, a productive network he long maintained. These included the Committee for Concerned Canadian Jews.
In addition to his academic career and advocacy work, Davis found inspiration in creative expression, writing poetry and composing music throughout his life. In 1986, he published a volume of poetry, Having Come This Far, and a book of prose, It Walks in Beauty in 2010.
At the age of 96, Davis passed away. The impact and influence of Davis’ work has been written about extensively, often noting how his intellect, compassion, creativity, and integrity manifest throughout his work and relationships.
He was survived by Natalie Zemon Davis (1928 - 2023), and their three children, Aaron Davis, Hannah Davis Taieb, and Simone Weil Davis.