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Positivism is the philosophical and methodological decision to base human knowledge solely on the scientific interpretation of observational data.
The positivist approach has been a "recurrent theme in the history of western thought from the Ancient Greeks to the present day". The concept was stated in the early 19th century by the philosopher and founding sociologist, Auguste Comte.
Comte, a sociologist, advocated a three stage model of human knowledge. He claimed that it had gone through the phases of a religious and metaphysical worldview before the scientific interpretation was considered. The positivistic method should, said Comte, no longer aim at a revelation of ultimate causes. It should rather focus on how data are linked together. Scientists would simply interpret these correlations. All human knowledge could only be relatively true, so Comte with a look at these interpretations. Late 19th-century philosophers of the sciences from Heinrich Hertz to Ernst Mach eventually discussed specific requirements of operable scientific theories and physical laws such as the predictability of results in experiments and the functionality of laws in computations.
In its strongest original formulation, positivism could be thought of as a set of five principles:
- The unity of the scientific method – i.e., the logic of inquiry is the same across all sciences (social and natural).
- The aim of science is to explain and predict.
- Scientific knowledge is testable. Research can be proved only by empirical means, not arguments alone. Research should be mostly deductive, i.e. deductive logic is used to develop statements that can be tested (theory leads to hypothesis which in turn leads to discovery and/or study of evidence). Research should be observable with the human senses. Arguments are not enough, sheer belief is out of the question.
- Science does not equal common sense. Researchers must be careful not to let common sense bias their research.
- Science should be as value-neutral as possible. The ultimate goal of science is to produce knowledge, regardless of any politics, morals, or values held by those involved in the research. Science should be judged by logic, and ideally produce universal conditionals:
- Experiments must be able to verify a statement anytime and anywhere.
Unlike materialists positivists do not make any claims about a primary substance such as matter. They assume that we have data and that we interpret these data. The idea of a material world of three dimensions is, for positivists, just a good model to handle common data in everyday life. If astronomy has to deal with more complex data that cannot be handled consistently in such a model, they will have to think of a different model. Early 20th-century positivists like Ernst Mach said that the best model is the most "economical" model, that is the model we can use best in calculations and predictions.
The idea that all physical laws could be simply useful dates back to Auguste Comte, who said that all theories were merely "relatively" true, and that even Isaac Newton's law of universal gravitationwere was strictly speaking nothing but a social convention - true until new data induce us to formulate a better theory.
Logical positivism [change]
It held not only that propositions were true or false, but that statements which could not be verified (shown to be either true or false) were meaningless. Thus statements like "There is a God" or "There is no God" are not true or false, but meaningless. The whole idea was explained in English by a famous little book by A.J. Ayer, Language, truth and logic in 1936.
This was the idea of P.W. Bridgman, Nobel Prize in Physics for 1946. It was that a concept in science was defined by the way one measured it. If one thinks of electron spin, or the curvature of space, these are not everyday ideas. In everyday life, electrons are not seen, and neither is space seen to be curved. They rest on the results of experiments which measured fundamental properties like time, light, mass, electrical charge, and so on. What Bridgman meant is that their meaning is in the way the measurements were done.
- The special theory of relativity depended on operational definitions for simultaneous events and distance, that is, providing the operations needed to define these terms.
- In quantum mechanics the notion of operational definitions is closely related to the idea of "observables", that is, definitions based upon what can be measured.
- Operationalism is found in other sciences. In psychology, intelligence has often been defined as the result of measurement by a standard IQ test. Obviously that is controversial, because our everyday understanding of the word "intelligence" is much more complex and varied.
Comtean positivism [change]
19th-century positivism – or "Comtean positivism" – included the outline of a proposed development. This would lead from primitive explanations, through religious thought and monotheism, to positivism as the universal theory and scientific practice. The theory was very influential among cultural historians. It led Comte to the creation a "religion of humanity" as a secular substitute for all religions. This caused an outcry among scientists, who were ready to adopt the scientific premises but not interested in creating a substitute religion.
One can today still visit temples in Rio de Janeiro, Porto Alegre, and Curitiba in Brazil, and Paris built by 19th-century Comtean positivists. London had a society of positivists. The Turkish leader Mustafa Kemal Atatürk was strongly interested in positivism as the basis of a secularisation of the nation, he was trying to build.
The term positivism is today no longer connected to the construct of a secular religion, but more to describe a scientific method.
- Cohen, Louis (2007), Research methods in education, Routledge, pp. 9, doi:10.1111/j.1467-8527.2007.00388_4.x
- Sociology Guide "Auguste Comte". Sociology Guide.
- See Bruce Caldwell's article on positivism in the The New Palgrave Dictionary of Economics, Second Edition, 2008. pdf
- Hacking I. ed 1981. Scientific revolutions. Oxford Univ. Press, New York.
- This rules out that scientists claim something to be true, because they conducted an experiment with that result at one time and though they realise that new experiments conducted elsewhere do not show the same result again.
- Ayer A.J. 1936 [2nd ed 1946]. Language, truth and logic. Gollancz, London.
- Bridgman P.W. 1927. The logic of modern physics. New York: Macmillan.
- Bridgman P.W. 1955. Reflections of a physicist. New York:Philosophical Library.
- NMJ Woodhouse (2003). Special relativity. London: Springer. p. 58. ISBN 1-85233-426-6. http://books.google.com/books?id=ggPXQAeeRLgC&pg=PA50&dq=isbn=1852334266#PPA58,M1.
- C. J. Isham (1995). Lectures on Quantum Theory. Imperial College Press. p. 95. ISBN 1-86094-001-3. http://books.google.com/books?id=xR3sS2hEFzcC&pg=PA95&dq=observable+operational+definition+quantum.
- Jiří Blank, Pavel Exner, Miloslav Havlíček (1994). Hilbert Space Operators in Quantum Physics. Springer. p. 252. ISBN 1-56396-142-3. http://books.google.com/books?id=V0BSIoGXHLQC&pg=PA252&dq=observable+operational+definition+quantum.
Further reading on positivism [change]
- Giddens, Anthony. Positivism and sociology. Heinemann. London. 1974.
- Mill, John Stuart. August Comte and positivism. web-books.com <http://www.web-books.com/Classics/Nonfiction/Philosophy/Mill_Comte/Home.htm>.
- Mises, Richard von. 1951. Positivism: a study in human understanding. Harvard University Press. Cambridge, Mass.
- Pickering, Mary. 1993. Auguste Comte: an intellectual biography. Cambridge University Press, Cambridge.
- Richard Rorty 1982. Consequences of pragmatism