Stanley Smith Stevens (November 4, 1906 – January 18, 1973) was an American psychologist who founded Harvard's Psycho-Acoustic Laboratory, studying psychoacoustics, and he is credited with the introduction of Stevens' power law. Stevens authored a milestone textbook, the 1400+ page "Handbook of Experimental Psychology" (1951). He was also one of the founding organizers of the Psychonomic Society. In 1946 he introduced a theory of levels of measurement widely used by scientists but criticized by statisticians.
In addition, Stevens played a key role in the development of the use of operational definitions in psychology. A Review of General Psychology survey, published in 2002, ranked Stevens as the 52nd most cited psychologist of the 20th century.
He was born in Ogden, Utah to Stanely and Adeline (Smith) Stevens and educated in Latter-day Saint-affiliated schools in Salt Lake City, Utah. He spent much of his childhood in the polygamous household of his grandfather Orson Smith. At the death of his parents in 1924, he spent the next 3 years on an LDS mission in Switzerland and Belgium. He attended the University of Utah from 1927 to 1929 and Stanford University for the next two years, graduating with an A.B. in psychology from Stanford in 1931. After two years of graduate study, he received his Ph.D. in psychology from Harvard University, where he served under Edwin Boring as assistant in psychology from 1932 to 1934. The following year, he spent studying physiology under Hallowell Davis at the Harvard Medical School and in 1935 became a research fellow in physics at Harvard for a year. In 1936, Stevens accepted a position as an instructor in Experimental Psychology at Harvard University.
He married Maxine Leonard in 1930 and had a son, Peter Smith, in 1936.
Science of Science Discussion Group
Stevens played a key role in organising the Science of Science Discussion Group in Cambridge Massachusetts. Stevens organised eight meetings from October 1940 to mid 1941 for this group. There the group attracted a range of participants whose aim was the "debabelisation of science". The group was influence by the 5th Congress of the Unity of Science, which had been held in Harvard University in September 1939. It attracted a range of well-known scientists from different disciplines.
He was mainly active in the fields of psychophysics and psychoacoustics. In one paper, he developed the measurement scale (Level of measurement) consisting of Nominal, Ordinal, Ratio, and Interval.