Horace Chandler (“Chan”) Davis (1926 – 2022) was a 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, mathematics education, ethics, and ethnobiology.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 U of T, he was active in Science for Peace, a leadership figure within a group of radical mathematicians, and campaigned against labour inequity on campus.**Early life and education**Professor Davis was born on August 12,1926 in Ithaca, New York. His parents, Horace “Hockey” Bancroft Davis and Marian “Nanie” 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. During his Harvard years, Davis took several music courses including orchestration with Walter Piston and advanced harmony with Irving Fine, whom he considered to be his mentor. Davis was recognized as a talented composer, an interest which he returned to seriously later in his life.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 and ensign for the US Navy in the fall 1945 and spring of 1946. The following fall 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, an anti-nuclear tale, “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.**House Un-American Activities Committee Hearing**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. By this time, Davis had let his membership in the CPUSA lapse. 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 [1] , led to his indictment for contempt of Congress. Davis viewed his actions as an expression of his continued and deep belief in a united left [2]. 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 the end of 1959, these efforts were exhausted, and Davis was found guilty and sentenced to six months in prison, which he served in 1960. Davis discusses his experiences and their impact in his 1988 essay, The Purge [2].**Academic career**In both the period after his dismissal from the University of Michigan and following his release from prison, Davis struggled to find employment, having been blacklisted by most American academic institutions. During this time he served as Editor for the American Mathematical Society’s Mathematical Reviews (1958 – 1961), received a National Science Foundation Postdoctoral Scholarship (1957 – 1958), and was appointed as a member of the Institute for Advanced Study (1957 – 1958). After his release from prison, he began considering Canadian institutions where other academics facing similar persecution had succeeded. He reached out to Donald Coxeter at U of T’s Department of Mathematics and in 1962 was hired by the University as Associate Professor. Natalie Zemon Davis also accepted a role in U of T’s Department of History 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 included among other topics geometry, fractal dragon curves (in particular, the Heighway dragon and twindragon), 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 [3] .His activism similarly connected him to numerous other organizations and individuals, a productive network he long maintained. These included anti-war efforts, such as through the Toronto Anti-Draft Programme, involvement in faculty, staff and student organizations across Toronto’s universities, and international networks focused on intellectual freedom. Davis also regularly responded to key issues through letters to the editor in Canadian and American media, in addition to becoming a target of right-wing press [5].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 in 2006, a second book of poetry, Held by the Word. A collection of his prose, It Walks in Beauty, came out in 2010. His musical output was at its most prolific in the last three years of his life, leading to a family-published collection of his art songs.At the age of 96, Davis passed away. The impact and influence of Davis’ work has been written about extensively, often recognizing 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.The ways in which the creators of archival records identify themselves and are identified by others is a key contextual aspect of understanding their perspectives and approach. Chandler Davis was socially understood as a white, cis-gendered man. He was part of a multigenerational New England family whose beliefs were rooted in Quaker and Unitarian teachings. Information has been gathered from family members.Footnotes[1] Batterson, Steve. The Prosecution of Chandler Davis : McCarthyism, Communism, and the Myth of Academic Freedom. New York: Monthly Review Press, 2023, p.77.[2] Information gathered from conversations with the Davis Family.[3] See Davis, Chandler, “The Purge” in AMS History of Mathematics, Volume 1: A Century of Mathematics in America, Part I, ed. Peter Dunn.[4] Wu, Calvin, 'I Am a Radical, and So Are You,' Science for the People Magazine, Vol. 25, No. 3, https://magazine.scienceforthepeople.org/vol25-3-killing-in-the-name-of/i-am-a-radical-and-so-are-you/[5] Weinberg, Paul. “Snooping in the Cold War” in Peace Magazine. Vol. 30, No. 1, 2014. https://peacemagazine.org/archive/v30n1p26.htm