Nagel, Ernest (1901–1985)

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NAGEL, ERNEST
(19011985)

Ernest Nagel, the American philosopher of science, was born at Nove Mesto, Czechoslovakia and came to the United States at the age of ten, becoming naturalized in 1919. He was graduated from City College in 1923 and received an MA in mathematics from Columbia in 1925 and a PhD in philosophy in 1930. He served as the John Dewey professor of philosophy at Columbia University from 1955 to 1966, then took the position of university professor there until 1970, becoming emeritus in 1970. He expressed indebtedness to the teachings of Morris R. Cohen, John Dewey, and Frederick J. E. Woodbridge and to the writings of Charles S. Peirce, Bertrand Russell, and George Santayana.

Philosophy of Science

Nagel belonged to the naturalist and logical empiricist movements, and he is primarily noted for his contributions to the philosophy of science. In 1934 he published, with Morris R. Cohen, An Introduction to Logic and Scientific Method. This noted text has been praised for its high level of rigor and for its enrichment of the traditional dry fare of logic with illustrations of the functions of logical principles in scientific method, in the natural and social sciences, and in law and history.

Nagel's book The Structure of Science is a unified and comprehensive distillation of many years of teaching and of his many publications on special aspects of scientific thought. It is the most complete exposition of Nagel's analysis of the nature of explanation, the logic of scientific inquiry, and the logical structure of the organization of scientific knowledge, and it illuminates the cardinal issues concerning the formation and the assessment of explanation in physics and in the biological and social sciences.

Two other contributions by Nagel to logic and the philosophy of science are Principles of the Theory of Probability (1939) and Gödel's Proof (1958), written in collaboration with James R. Newman. These studies range over many issues, from the logic of probable inference to the basic conditions of the structure of formal systems.

General Philosophy

Two philosophical essays of a general scope by Nagel have been widely acclaimed. In "Logic without Ontology" Nagel defended a naturalistic interpretation of logic. He argued that logico-mathematical principles must be understood according to their functions in specific contexts, namely, in inquiries, and he criticized attempts to adduce an ontological ground or transcendent authority for the meaning, warrant, and necessary character of logical laws. Nagel had already repudiated his early view that logical principles "are inherently applicable because they are concerned with ontological traits of utmost generality" (An Introduction to Logic and Scientific Method, p. v). In "Logic without Ontology" he showed that the view that logic is ontologically determined or entails ontological commitments arises primarily from a failure to heed certain contextual and operational qualifications of the sense in which logical principles are supposed to possess "necessary truth."

In "Sovereign Reason" Nagel presented a penetrating critique, focused on the doctrine of internal relations, of Brand Blanshard's rational idealism. This critique exemplifies one of Nagel's strongest philosophical convictions and a main theme of "Logic without Ontology": Logical principles (and even pure Reason), just because they are analytic, are necessary but not sufficient instruments for acquiring knowledge or discovering truths about reality. The task of logic, according to Nagel, is to disclose the assumptions and clarify the methods on which responsible claims to knowledge are based and by which they are critically assessed. All claims to knowledge, even those most impressively supported by evidence and experiment, are subject to revision or rejection in the light of new advances in knowledge. This empiricist tenet led Nagel to accept contingency as a real trait of nature and fallibility as an inescapable feature of human inquiry.

Science and Society

Nagel's technical interest in the logic and history of scientific knowledge did not prevent him from appreciating the social consequences and problems of science and technology in a democratic society. Much of his critical activity as a speaker, reviewer, and essayist was devoted to imparting a clearer understanding of the nature of science and to dispelling philosophical vagaries and bizarre notions concerning such matters as causality and indeterminism in physics; the alleged paradoxical character of abstract science or its utter disparity with common sense; the frequent claims that science is value-free, or metaphysically inspired, or mere codified sense data; and the revulsion or despair and the impassioned remedies that science has occasioned in some literary and theological circles.

Materialism, Determinism, and Atheism

Nagel's philosophical naturalism led him to take a decisive stand on certain broad philosophical issues, notably materialism, determinism, and atheism. It has been charged that naturalists, being materialists, are unable to account for mental phenomena. Nagel replied, fully aware of the many senses of the word materialism, that naturalists are not materialists if materialism is taken to mean that such psychological predicates as "fear" or "feeling of beauty" logically entail or are reducible to physical terms such as weight, length, or molecule. Although he repudiated reductive materialism, Nagel held that mental events are aspects of and contingent on the organization of human bodies. Events, qualities, and processes are dependent on the organization of spatially and temporally located bodies. In this sense, naturalism is committed to materialism: Organized matter has a causal primacy in the order of nature. It follows that there can be no occult forces or disembodied spirits directing natural events and no personal immortality when bodily organizations disintegrate.

To assess the role of determinism in history and in ethical theory, Nagel formulated the meaning of determinism in natural science. A scientific theory is deterministic with respect to a set of properties when, given a specification of the set at any initial time, a unique set of the properties for any other time can be deduced by means of the theory. The theory might be a mechanical theory, and the sets of properties mechanical states. This theory might conceivably be of use in calculating the mechanical states of a human organism, but only its mechanical states. Whether other properties of the organism and its history were deterministic would remain an open empirical question. Nor would determinism in human history, if it were established, automatically empty moral endeavor and responsibility of significance. Which modes of human experience and behavior, if any, are subject to deterministic theory remains an empirical question; and the sense in which these conditions might be characterized as "deterministic" remains an issue of analysis.

In several places, including his influential paper "The Causal Character of Modern Physical Theory," Nagel concerned himself with the philosophical implications of quantum theory. Like Albert Einstein and Max Planck, but unlike the majority of writers on the subject, Nagel denied that quantum theory has indeterministic consequences. He also showed in some detail how intellectual confusion thrives when distinctions of context and the relevance of theoretical language to specific contexts are ignored; for example, when "particle" in the context of Newtonian theory is transported into discussions of the uncertainty principle in modern physics. In another well-known essay, "Russell's Philosophy of Science," Nagel argued that the physical and physiological facts of perception do not require the abandonment of common sense in favor of the strange conclusions held by Russell and Arthur Stanley Eddington.

Nagel was one of the few naturalists to present a forthright statement of the naturalist critique of theism. His formulation of atheism is not couched as a sheer negation of theism but proceeds from a positive moral position according to which, while it is granted that there are inevitable tragic aspects of life, knowledge of life and nature is to be preferred to illusions. On matters of such supreme moment, the truth rather than fiction is the more fitting ideal of rational men.

Nagel did not, however, deny the value and authenticity of other than purely cognitive pursuits. He never argued that aesthetic qualities, ideals, suffering, and enjoyments are not genuine aspects of experience. On the contrary, he urged that naturalism, although obliged to render a competent account of scientific knowledge, also include in its scope a place for imagination, liberal values, and human wisdom.

See also Atheism; Determinism, A Historical Survey; Materialism; Philosophy of Science, History of.

Bibliography

works by nagel

On the Logic Measurement. New York, 1930.

An Introduction to Logic and Scientific Method. New York: Harcourt Brace, 1934. Written with Morris R. Cohen.

Principles of the Theory of Probability. Chicago: University of Chicago Press, 1939. Vol. I, No. 6, of The International Encyclopedia of Unified Science.

"Russell's Philosophy of Science." In The Philosophy of Bertrand Russell, edited by P. A. Schilpp. Evanston, IL: Open Court, 1944. Reprinted in Sovereign Reason.

"Logic without Ontology." In Naturalism and the Human Spirit, edited by Y. H. Krikorian. New York: Columbia University Press, 1944. Reprinted in Logic without Metaphysics (see below).

"Are Naturalists Materialists?" Journal of Philosophy 42 (1945): 515530. Reprinted in Logic without Metaphysics.

"Sovereign Reason." In Freedom and Experience. Essays Presented to Horace M. Kallen, edited by Sidney Hook and Milton R. Konvitz. Ithaca, NY: Cornell University Press, 1947. Reprinted in Sovereign Reason.

"The Causal Character of Modern Physical Theory." In Freedom and Reason, edited by S. W. Baron, Ernest Nagel, and K. S. Pinson. Glencoe, IL: Free Press, 1951. Reprinted with revisions as part of Ch. 10 in The Structure of Science.

Sovereign Reason. Glencoe, IL: Free Press, 1954.

Logic without Metaphysics. Glencoe, IL: Free Press, 1956.

Gödel's Proof. New York: New York University Press, 1958. Written with James R. Newman.

"A Defense of Atheism." In Basic Beliefs, edited by J. E. Fairchild. New York: Sheridan House, 1959.

The Structure of Science. New York: Harcourt Brace, 1961.

Philosophy, Science, and Method: Essays in Honor of Ernest Nagel, edited by Sidney Morgenbesser, Patrick Suppes, and Morton Gabriel White. New York: St. Martin's, 1969.

With Sylvain Bromberger and Adolf Grünbaum, Adolf. Observation and Theory in Science. Baltimore, MD: Johns Hopkins, 1971.

Teleology Revisited and Other Essays in the Philosophy and History of Science. New York: Columbia University Press, 1979.

H. S. Thayer (1967)

Bibliography updated by Michael J. Farmer (2005)