Published online by Cambridge University Press: 28 February 2022
Two doubtful philosophical doctrines have contributed strongly to the development of IQ tests, and now play a major role in defending IQ tests as measures of intelligence: they are operationism and fictionalism.
The application of operationism in psychometrics is in such doctrines as the following: one can avoid answering the question whether IQ tests measure intelligence simply by defining the word ‘intelligence’ as what IQ tests measure. Obviously, such a definition does not avoid the issue. For we can now reasonably ask whether people who accept the operational definition use the word ‘intelligence’ to refer to the same quantity as that referred to by people who reject the operational definition or have never considered it. Many operational definitions of ‘intelligence’ would be clearly unsatisfactory. Consider, for example, an operational definition which stipulates that a person's intelligence is the number of pounds indicated when the person is placed on a scale.
I would like to thank the following persons for their comments on earlier versions of this material: Richard Boyd, Susan Carey, L. J. Cronbach, Gerald Dworkin, Jerry Fodor, Paul Horwich, John Loehlin, Tom Nagel, Hilary Putnam, and Tim Scanlon. Earlier versions of much of this material were included in my contribution to Block and Dworkin (1974).