Stanley Smith Stevens (November 4, 1906 – January 18, 1973) was an American

psychologist A psychologist is a professional who practices psychology and studies mental states, perceptual, cognitive, emotional, and social processes and behavior. Their work often involves the experimentation, observation, and explanation, interpretatio ...

who founded

Harvard Harvard University is a private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher lear ...

's Psycho-Acoustic Laboratory, studying

psychoacoustics Psychoacoustics is the branch of psychophysics involving the scientific study of the perception of sound by the human auditory system. It is the branch of science studying the psychological responses associated with sound including noise, speech, ...

, and he is credited with the introduction of

Stevens's power law Stevens' power law is an empirical relationship in psychophysics between an increased intensity or strength in a physical stimulus and the perceived magnitude increase in the sensation created by the stimulus. It is often considered to supersed ...

. 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 The Psychonomic Society is an international scientific society of over 4,500 scientists in the field of experimental psychology. The mission of the Psychonomic Society is to foster the science of cognition through the advancement and communicatio ...

. In 1946 he introduced a theory of

levels of measurement Level of measurement or scale of measure is a classification that describes the nature of information within the values assigned to dependent and independent variables, variables. Psychologist Stanley Smith Stevens developed the best-known class ...

widely used by scientists but whose use in some areas of

statistics Statistics (from German language, German: ', "description of a State (polity), state, a country") is the discipline that concerns the collection, organization, analysis, interpretation, and presentation of data. In applying statistics to a s ...

has been criticized. In addition, Stevens played a key role in the development of the use of operational definitions in psychology. A ''

Review of General Psychology ''Review of General Psychology'' is the quarterly scientific journal of the American Psychological Association Division 1: The Society for general psychology. The journal publishes cross-disciplinary psychological articles that are conceptual, theo ...

'' survey, published in 2002, ranked Stevens as the 52nd most cited psychologist of the 20th century. He was a member of the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (The Academy) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, and other ...

, the United States

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, NGO, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the ...

, and the

American Philosophical Society The American Philosophical Society (APS) is an American scholarly organization and learned society founded in 1743 in Philadelphia that promotes knowledge in the humanities and natural sciences through research, professional meetings, publicat ...

Life

Stevens was born in

Ogden, Utah Ogden ( ) is a city in and the county seat of Weber County, Utah, Weber County, Utah, United States, approximately east of the Great Salt Lake and north of Salt Lake City. The population was 87,321 in 2020, according to the United States Census ...

, to Stanley and Adeline (Smith) Stevens and educated in

Latter-day Saint The Latter Day Saint movement (also called the LDS movement, LDS restorationist movement, or Smith–Rigdon movement) is the collection of independent church groups that trace their origins to a Christian Restorationist movement founded b ...

-affiliated schools in

Salt Lake City, Utah Salt Lake City, often shortened to Salt Lake or SLC, is the List of capitals in the United States, capital and List of cities and towns in Utah, most populous city of the U.S. state of Utah. It is the county seat of Salt Lake County, Utah, Salt ...

. He spent much of his childhood in the

polygamous Polygamy (from Late Greek , "state of marriage to many spouses") is the practice of marrying multiple spouses. When a man is married to more than one wife at the same time, it is called polygyny. When a woman is married to more than one h ...

household of his maternal grandfather Orson Smith. At the death of his parents in 1924, he spent the next 3 years on an LDS mission in

Switzerland Switzerland, officially the Swiss Confederation, is a landlocked country located in west-central Europe. It is bordered by Italy to the south, France to the west, Germany to the north, and Austria and Liechtenstein to the east. Switzerland ...

and

Belgium Belgium, officially the Kingdom of Belgium, is a country in Northwestern Europe. Situated in a coastal lowland region known as the Low Countries, it is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeas ...

. He attended the

University of Utah The University of Utah (the U, U of U, or simply Utah) is a public university, public research university in Salt Lake City, Utah, United States. It was established in 1850 as the University of Deseret (Book of Mormon), Deseret by the General A ...

from 1927 to 1929 and

Stanford University Leland Stanford Junior University, commonly referred to as Stanford University, is a Private university, private research university in Stanford, California, United States. It was founded in 1885 by railroad magnate Leland Stanford (the eighth ...

for the next two years, graduating with an A.B. in psychology in 1931. Shortly after arriving in Massachusetts to begin a Ph.D., he left the LDS church, but continued to struggle with conflicting ideas of faith and science. After two years of graduate study, he received his Ph.D. in psychology from

Harvard University Harvard University is a Private university, private Ivy League research university in Cambridge, Massachusetts, United States. Founded in 1636 and named for its first benefactor, the History of the Puritans in North America, Puritan clergyma ...

, where he served under

Edwin Boring Edwin Garrigues (Garry) Boring (October 23, 1886 – July 1, 1968) was an American experimental psychologist, Professor of Psychology at Clark University and at Harvard University, who later became one of the first historians of psychology. A ' ...

as assistant in psychology, from 1932 to 1934. The following year he spent studying physiology under

Hallowell Davis Hallowell Davis (August 31, 1896 – August 22, 1992) was an American physiologist, otolaryngologist and researcher who did pioneering work on the physiology of hearing and the inner ear. He served as director of research at the Central Ins ...

Harvard Medical School Harvard Medical School (HMS) is the medical school of Harvard University and is located in the Longwood Medical and Academic Area, Longwood Medical Area in Boston, Massachusetts. Founded in 1782, HMS is the third oldest medical school in the Un ...

, and in 1935 served as 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 Stevens, in 1936. He married Geraldine Stone, who had worked in the Psycho-Acoustic Laboratory from its inception, in 1963.

Science of Science discussion group

Stevens played a key role in organising the

Science of Science discussion group Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which stu ...

Cambridge, Massachusetts Cambridge ( ) is a city in Middlesex County, Massachusetts, United States. It is a suburb in the Greater Boston metropolitan area, located directly across the Charles River from Boston. The city's population as of the 2020 United States census, ...

, which met on eight occasions from October 1940 to mid-1941. Stevens, who was noted for the clarity of his scientific writing, attracted to the group a number of participants whose aim was the "debabelisation of science". The group was also influenced by the 5th Congress of the Unity of Science, which had been held at

in September 1939 and featured a number of well-known scientists from different disciplines.

Work

Stevens' experimental and theoretical work lay primarily in the fields of

psychophysics Psychophysics is the field of psychology which quantitatively investigates the relationship between physical stimulus (physiology), stimuli and the sensation (psychology), sensations and perceptions they produce. Psychophysics has been described ...

and

. One of his most influential contributions was his definition of a measurement scale defined by four types: Nominal, Ordinal, Interval, and Ratio. (see

Level of measurement Level of measurement or scale of measure is a classification that describes the nature of information within the values assigned to variables. Psychologist Stanley Smith Stevens developed the best-known classification with four levels, or scale ...

) He is the author of the operational theory of measurement, which “...in the broadest sense, is defined as the assignment of numerals to objects or events according to rules.” In fact, the definition paraphrased Campbell's note from the Final Report of the so-called Ferguson's committee (joint committee of sections A, Mathematical and Physical Sciences, and J, Psychology, of the British Association for the Advancement of Science, held 1932–1940). Stevens just omitted or extended some of Campbell's assumptions. While Campbell considered additivity to be a necessary condition, Stevens considered any rule to fit the definition. His goal was to overcome the committee's conclusion concerning the possibility of measurement in psychology.

References

* * Nicholson, I. (2000). "S.S. Stevens". In Alan E. Kazdin (Ed.), ''Encyclopedia of Psychology.'' Washington, DC: American Psychological Association Press. * Nicholson, I. (2005). "From the Book of Mormon to the Operational Definition: The Existential Project of S.S. Stevens". In William Todd. Schultz (Ed.), ''Handbook of Psychobiography'' (pp. 285–298). New York: Oxford University Press.

Life

Science of Science discussion group

Work

See also

References

Further reading