Cassius Jackson Keyser

Cassius Jackson Keyser was born in Rawson, Ohio on May 15, 1862. His father, Jacob B. Keyser, was a farmer while his mother, Margaret Jane (Ryan), kept the house and the children. Cassius, as well as three older siblings, Charlotte, Calvin, and Alonzo (Chester) , all attended school in Union Township, Hancock County. In the 1870’s the family moved to Marion Township in Hardin County.

In 1879 Cassius entered the North West Ohio Normal School (now Ohio Northern University) in Ada, Ohio where he began his studies. While on campus he took courses in Mental Arithmetic, Higher Arithmetic, Higher Algebra, Geometry, Trigonometry, Grammar, Geography, History, Botany, Natural Philosophy, Chemistry, Zoology, Rhetoric, Logic, Civil Government, Surveying and Engineering, Latin, and others. He completed a scientific degree and was selected to give an oration at the May, 1883, commencement ceremonies for the N.W.O.N.S. where he spoke under the title Harmony Between Reason and Belief. He married a fellow student from N.W.O.N.S., Ella Maud Crow of Ridgeway, Ohio, on August 19, 1885.

After commencement, Cassius Keyser served as the school principal and superintendent in Ridgeway, Ohio and then held a similar position in Plattsburg, Missouri. He taught as an Instructor of Mathematics at the University of Missouri and earned his Bachelor of Science degree from that institution in 1892. After short tenures as a mathematics instructor at New York State Normal School (New Paltz, New York) and Washington University (St. Louis), Keyser continued his education at Columbia University in New York City. He received his M.A. in Mathematics in 1896 and his Ph.D. in Mathematics in 1901, both from Columbia University. His mathematical interests included geometry, history, and philosophy.

Dr. Keyser’s affiliation with Columbia University continued long after receiving his degrees. He served there as an Instructor of Mathematics (1900-1903), an Adjunct Professor of Mathematics (1903-04), and then the Adrain Professor of Mathematics (1904-1927). He also served as the Mathematics Department Chair from 1910 to 1916. Among students he was admired as a teacher who took great care with his lectures even if he was a "little old-fashioned in his style and a trifle long-winded." (Newman 1537) During his time at Columbia, he conducted a seminar on the newly published Principia Mathematica by Bertrand Russell and Alfred North Whitehead. Those in attendance at the seminar included mathematician and logician Emil Post. Cassius Keyser retired from Columbia University in 1927 as the Adrain Professor Emeritus of Mathematics.

Throughout his academic career, Dr. Keyser was a prolific writer and lecturer especially in the area of mathematical philosophy. Included among his more than fifty works were titles such as Mathematical Philosophy: A Study of Fate and Freedom (Lectures for the Educated Laymen), The Human Worth of Rigorous Thinking, and Mathematics and the Question of the Cosmic Mind, with Other Essays. James R. Newman, in his classic 1956 four-volume The World of Mathematics, included Cassius J. Keyser’s The Group Concept as one of two articles on group theory. General semantics, the field which examines the foundations of the structures of mathematics and the sciences and attempts to apply these structures to human interactions, was introduced by Alfred Korzybski in 1933 in his Science and Sanity. Korzybski credited C.J. Keyser as having an important influence on both himself and the beginnings of the field of general semantics. In describing game theorist John von Neumann, it has been said that, "He was a living fulfillment of the way of applying the power of abstract axiomatics and formal systems that had been envisioned in the ideals of Cassius Keyser and Alfred North Whitehead." ( Historical Highlights 2) Dr. Keyser’s writings in mathematical philosophy had a definite influence on those who followed him.

Among his other achievements, Dr. C.J. Keyser, along with fellow Columbia University professor John Dewey, was one of the members of the organizing committee for the American Association of University Professors (AAUP). On April 25, 1914, at a meeting of the organizing committee, C.J. Keyser made the motion that "The purposes of the Association shall be to promote a more general and methodical discussion of problems relating to education in higher institutions of learning; to create means for authoritative expression; to make collective action possible; and in general to maintain and advance the ideals and standards of the profession." ("Original Purposes"1) The AAUP is now an organization of over 45,000 members. Dr. Keyser was also a fellow of the American Academy for the Advancement of Science as well as a Vice-President for Section A of this organization. He was a member of the American Mathematical Society and an Associate Editor of Scripta Mathematica. He served as the Mathematics Editor for the Encyclopedia Americana in 1906 and served on the editorial board for the Hibbert Journal. Cassius Keyser enjoyed and devoted much time to his work, but was also "full of fun and nonsense". He was a music lover who "played the fiddle, but he gave it up because it would rob his time from mathematics." (Carter 84)

Dr. Cassius J. Keyser died at nearly the age of 85 on May 8, 1947 at his home in New York City. His obituary appeared in the New York Times on May 9, 1947. A group of his colleagues and friends had already formed The Society of Friends of Cassius Jackson Keyser. The purpose of this group was to publish the remainder of Keyser’s unpublished essays. The first volume was to have been presented at his 85th birthday (a week after his death).



Carter, Elton S. "Cassius Jackson Keyser." General Semantics Bulletin 10-11 (1952): 84-85.

Historical Highlights in the Application of Mathematical Modeling to Games Up to the Beginning of the Cold War. Playbox. 6 February 2002

Newman, James R. The World of Mathematics. Vol 3. New York: Simon and Schuster, 1956.

"Original Purposes of AAUP." Tennessee Conference — American Association of University Professors. 28 November 2001 http://web/

"Prof. C.J. Keyser of Columbia, 85." New York Times 9 May 1947: 21.


Article by Tena Roepke
Ohio Northern University