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Cohen, Morris R.

Cohen, Morris R.



Morris Raphael Cohen (1880–1947), American philosopher, was born in the ghetto of Minsk, Russia. In 1892 he was brought to New York City. At an early age he became a skeptic and agnostic, yet the traditional Judaic veneration for learning as well as a certain piety of spirit remained with him all his life. The hardships of life on New York’s Lower East Side made him sympathetic to socialism. Inspired by Thomas Davidson, the Scottish scholar who lectured at the Educational Alliance settlement house, Cohen and fellow David-sonians established the “Breadwinners’ College” for the cultural education of the wage earner.

In 1900 Cohen received a B.S. from the College of the City of New York. From 1902 to 1904 he took graduate courses at Columbia University under Wilmon Sheldon, Charles A. Strong, Franklin H. Giddings, Henry R. Seager, and Frederick Woodbridge. He then studied at Harvard under William James, Josiah Royce, Hugo Münsterberg, and Crawford H. Toy, receiving his ph.d. in 1906. He wrote his thesis on Kant’s doctrine of happiness.

In 1906 Cohen married Mary Ryshpan, who had also been a student of Davidson’s. He taught mathematics at Townsend Harris Hall, the preparatory school to the College of the City of New York. From 1912 until his retirement in 1938 he was a professor at the college, where, besides teaching classes in logic, ethics, metaphysics, and the history of philosophy, he created courses in the philosophy of law, of science, and of civilization. From 1938 to 1941 he was professor of philosophy at the University of Chicago. He also taught or lectured at Columbia, Johns Hopkins, Yale, Stanford, Harvard, the New School for Social Research, and the law schools of Columbia, St. John’s, Yale, Harvard, Cornell, the University of Buffalo, and others. After the advent of Hitler, he became the principal founder and president of the scholarly Conference on Jewish Relations. His strenuous activities on behalf of this organization, and his chairing of a Jewish research institute on peace and postwar studies, undermined his frail health. He died in Washington, D.C., in 1947, survived by three children : the late Dr. Felix S. Cohen who was principal editor of his father’s posthumously published works, Dr. Leonora Cohen Rosenfield, and Dr. Victor William Cohen, a nuclear physicist.

Cohen’s elaboration and use of scientific method lent unity to his philosophy, even though he never lived to finish its elucidation. The notion that abstract logical or mathematical relations are real, which he accepted after reading Bertrand Russell’s Principles of Mathematics (1903), justified for him the procedure of science and served as his first guide for his independent work in philosophy.

The principle of polarity he called his second guide to systematic philosophy: opposing poles must be taken into account in explaining anything. For example, the world, which is the object of science, is a union of form and matter. Cohen made wide use of the concept of polarity, considering it both a heuristic and an ontological principle. His idea of polarity proved influential even outside of philosophy; John R. Commons, for example, applied it to economics.

Cohen envisaged further development of his idea of relationality when he discussed the theory of relativity with Einstein. He reasoned that if relations are real, then apparently polar assertions—for example, that something is both good and bad—may both be true when properly completed. He considered this a fruitful approach to problems in the natural and social sciences.

He accepted Charles Peirce’s pragmatism to the extent of asserting that “the way to make our ideas clear is to examine … all their possible implications. [Logical pragmatism] is an attempt to extend the experimental method to the handling of ideas” (Rosenfield 1962, p. 326).

Scientific method, according to Cohen, is based on systematic doubt. We cannot begin with either pure facts or pure theory; both are necessary. Assumptions should be reduced to a minimum and always made explicit. Constant self-correction is important and is achieved by considering alternative hypotheses. Conclusions can be drawn only after observation, collection of evidence, measurement, experimentation, and testing of hypotheses. The hypothesis that is at the same time simplest, widest, and in best agreement with the facts is always favored. The ideal of scientific method is the interconnection of facts into a unitary system. This exposition by Cohen was widely acclaimed.

His social philosophy embodied the liberalism of a rationalist. It was based on the application of logic and scientific method to the social sciences. “Tolerance, the avoidance of fanaticism, and above all a wider and clearer view of the nature of our beliefs and their necessary consequences, is thus a goal or end which the development of logic serves. In this sense logic is a necessary element of any liberal civilization” (1944, p. 187). He considered logic to be the lifeblood of philosophy, the formal aspect of all being, in and out of space time. Appropriately, he called his intellectual autobiography “The Faith of a Logician” (1930).

He was the first North American philosopher to concern himself seriously with the law. He considered the law to be ever changing, with the sources of its growth or change lying in social facts, legal systems, and ethical ideals. A judge’s decisions are influenced by his opinions on social and economic questions. When applied to legal problems, Cohen’s use of logic, the scientific method, polarity, and pragmatism all seem to be particularly cogent. Legal thought, with its balance between the rational and the empirical, the theoretical and the practical, ap-pealed to his underlying moral passion. Cohen’s influence was felt perhaps most deeply in the field of law, not only because of the range, flexibility, and progressive character of the concepts he applied to it, but also because he had direct contact with the leading legal figures of his day, including Oliver Wendell Holmes, Jr., Felix Frankfurter, and many others.

The philosophy of history was considered by Cohen to be the focal point of all applications of history to life. At its best, history is more than a science that deals with evidence critically; as Cohen conceived of it in The Meaning of Human History (1947), it should also be artistic reconstruction. The historian makes value judgments, wittingly or unwittingly. The philosophy of history should then concern itself with the scientific and rational study of ethics.

For all his dedication to rationality and his belief in the reality of logical relations, Cohen considered the ultimate laws of nature to be contingent. In the preface of Reason and Nature (1931), he called himself a mystic—because he believed that words point to a realm of being deeper and wider than the words themselves—and an idealist in the Platonic sense—because he believed that abstract universals are real, not nominal. He admired Spinoza’s amor Dei intellectualis and defined God, a word he rarely used, as an ideal of holiness. As a naturalist he did not believe in disembodied spirits, but he also rejected the materialist view that consciousness can be explained in purely physical terms. He considered consciousness to be a real addition to the phenomena of nature.

Like William James, Cohen thought that philosophy was for everyone, and he wrote accordingly. He was a prolific author, clear and pithy. Between 1914 and 1926 much of his writing appeared in the New Republic, which helped spread his influence in nonacademic circles.

He remained friendly to socialism but condemned communism. Despite his commitment to the contemplative life, he championed social causes and defended individuals subject to injustice or discrimination. Ernest Nagel called him a knight-errant in the cause of human enlightenment. He delighted in swimming against the currents of his time. According to John Dewey, his only fear was that someone might agree with him. He eschewed indoctrination and left no school of followers. Yet he was a famous teacher, and many distinguished philosophers, as well as leaders in other fields, were his students. For Huntington Cairns, he was, with John Dewey, the most influential of contemporary thinkers. Bertrand Russell was quoted by Harold Laski as saying that Cohen was the most significant philosopher in the United States.

A Socratic figure, an encyclopedic philosopher, an interdisciplinary pioneer and animateur, Cohen dedicated himself to his compelling sense of the exalted function of philosophy.

Leonora Cohen Rosenfield

[See alsoJurisprudence; Legal reasoning; Science; and the biographies ofCommons; Holmes; James; Peirce.]


(1923) 1956 Introduction. In Charles S. Peirce, Chance, Love and Logic: Philosophical Essays. New York: Braziller.

(1930) 1959 The Faith of a Logician. Pages 3–32 in Morris R. Cohen, Studies in Philosophy and Science. New York: Ungar.

(1931) 1953 Reason and Nature: An Essay on the Meaning of Scientific Method. 2d ed. Glencoe, iii.: Free Press. → A paperback edition was published in 1964.

1933 Law and the Social Order: Essays in Legal Philosophy. New York: Harcourt.

1934 Cohen, Morris R.; and Nagel, ErnestAn Introduction to Logic and Scientific Method. New York: Harcourt.

1940 Cohen, Morris R. et al. Generalization in the Social Sciences. Pages 227–273 in Louis Wirth (editor), Eleven Twenty-six: A Decade of Social Science Research. Univ. of Chicago Press.

1944 A Preface to Logic. New York: Holt. → A paperback edition was published in 1956 by Meridian.

1946 The Faith of a Liberal: Selected Essays. New York: Holt.

(1947) 1961 The Meaning of Human History. 2d ed. La Salle, iii.: Open Court.

(1948) 1958 Cohen, Morris R.; and Drabkin, Israel E. A Source Book in Greek Science. Cambridge, Mass.: Harvard Univ. Press.

1949a A Dreamer’s Journey: The Autobiography of Morris Raphael Cohen. Boston: Beacon.

(1949b) 1959 Studies in Philosophy and Science. New York: Ungar.

1950 Reason and Law: Studies in Juristic Philosophy. Glencoe, iii.: Free Press. → A paperback edition was published in 1961 by Collier.


Cairns, Huntington 1960 The Legal Philosophy of Morris R. Cohen. Vanderbilt Law Review 14:239–262.

Deregibus, Arturo 1960 Il razionalismo di Morris R.Cohen nella filosofia americana d’oggi. Turin (Italy): Giappichelli.

Konvitz, Milton R. 1951 The Life and Mind of Morris R. Cohen. Pages 11–31 in Salo W. Baron (editor), Freedom and Reason: Studies in Philosophy and Jewish Culture, in Memory of Morris Raphael Cohen. Glencoe, iii.: Free Press.

Kuhn, Martin A. 1957 Morris Raphael Cohen: A Bibliography. New York: City College of New York Library.

Larsen, Robert E. 1959 Morris Cohen’s Principle of Polarity. Journal of the History of Ideas 20:587–595.

Nagel, Ernest 1957 Morris R. Cohen in Retrospect. Journal of the History of Ideas 18:548–551.

Rosenfield, Leonora [Cohen] 1962 Portrait of a Philosopher: Morris R. Cohen in Life and Letters. New York: Harcourt.

Russell, Bertrand (1903) 1938 Principles of Mathematics. New York: Norton.

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