Jennings, Herbert Spencer, 1868-1947, American zoologist, b. Tonica, Ill., B.S. Univ. of Michigan, 1893, Ph.D. Harvard, 1896. He was professor of zoology at Johns Hopkins (1906-10) and did research on genetics (especially heredity and variation in microorganisms) and on animal behavior there from 1910 to 1938 and from 1939 at the Univ. of California. His demonstration that physical and chemical stimuli produce responses in lower animals disproved the current belief that their behavior was controlled by will and intelligence. His works include Behavior of the Lower Organisms (1906), The Biological Basis of Human Nature (1930), and Genetics (1935).

Hadley, Herbert Spencer, 1872-1927, American lawyer, b. Olathe, Kans. As attorney general of Missouri (1905-9), he successfully prosecuted the Standard Oil Company for violating the state antitrust law. He was governor of Missouri from 1909 to 1913 and was a prominent supporter of Theodore Roosevelt. In 1923 he became chancellor of Washington Univ. in St. Louis. He was on the committee of the American Law Institute which prepared the Code of Criminal Procedure, a model code published in 1930.

Gasser, Herbert Spencer, 1888-1963, American physiologist, b. Platteville, Wis., grad. Univ. of Wisconsin (B.A., 1910; M.A., 1911), M.D. Johns Hopkins, 1915. From 1931 to 1935 he was professor of physiology at the medical college of Cornell Univ. He was director of the Rockefeller Institute for Medical Research from 1935 to 1953. Gasser shared the 1944 Nobel Prize in Physiology or Medicine with Joseph Erlanger for their work on the electrophysiology of nerves, using a cathode-ray oscillograph.

(born April 27, 1820, Derby, Derbyshire, Eng.—died Dec. 8, 1903, Brighton, Sussex) English sociologist and philosopher, advocate of the theory of social Darwinism. His System of Synthetic Philosophy, 9 vol. (1855–96), held that the physical, organic, and social realms are interconnected and develop according to identical evolutionary principles, a scheme suggested by the evolution of biological species. This sociocultural evolution amounted to, in Spencer's phrase, “the survival of the fittest.” The free market system, without interference by governments, would weed out the weak and unfit. His controversial laissez-faire philosophy was praised by social Darwinists such as William Graham Sumner and opposed by sociologists such as Lester Frank Ward. Liked or loathed, Spencer was one of the most discussed Victorian thinkers.

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