Applied & Preventive Psychology 11 (2004) 45–46

Commentary

Constructs, operational definition, and operational analysis

Arthur C. Houtsa,∗, Scott Baldwinb

a West Clinic, 100 Humphreys Boulevard North, Suite 100, Memphis, TN 38120, USAb Department of Psychology, Psychology Building 212, University of Memphis, Memphis, TN 38152, USA

Abstract

We argue that a certain picture of the relationship between language and the world informed Meehl’s outlook on how science worked. Thatpicture authorized talk about constructs and has led to construct proliferation and other problems. Operational analysis offers an alternativeview and suggests that a major shortcoming of soft psychology is its lack of disciplined limits on acceptable verbal behavior.© 2004 Elsevier Ltd. All rights reserved.

Keywords:Constructs; Operational definition; Operational analysis; Verbal behavior

This commentary focuses on the first four paragraphs ofSection 15 ofMeehl’s (1978)paper and addresses what wethink are problems with Meehl’s theory of constructs, par-ticularly the assumed relationship between language and theworld. Certainly, Meehl’s paper is about more than con-structs, but we believe one reason for the slow progress ofsoft psychology is the widespread acceptance of constructsand mistaken ideas about their place in scientific psychol-ogy. Soft psychology is awash in constructs, and an opera-tional analysis of the notion of constructs shows where theconceptual missteps are taken.

Meehl’s view of science had its roots in classical logicalempiricism. This analysis was based on what is now rec-ognized as a questionable interpretation of the history ofphysics and was presented asthe fundamental model forall science. On this view, scientific theories contain threeclasses of statements: theoretical, observational, and corre-spondence rules. Accordingly, it is permissible and desirableto introduce abstract terms or concepts because these can besubjected to formal logical operations and new concepts canbe introduced or derived. What makes science different fromphilosophy or pure logic is the notion that the abstract termsare tied via correspondence rules to observations; hence log-ical empiricism.Meehl (1978)cited Hempel’s picture of ascientific theory as a logical net of law like statements float-ing above the sea of observations. No matter where one ison that Platonic net there is always a way back down to thesensory world or ordinary observation. In this picture, it isacceptable to define abstract constructs in terms of other ab-

∗E-mail address:ahouts@bigfoot.com (A.C. Houts).

stract constructs as long as there is someeventualconnec-tion, via the correspondence rules, to the concrete.

The chief correspondence rule in this scheme of scienceand psychology was operational definition. In psychology,operational definition became a pointing procedure, whereabstract constructs point to objects (or behaviors) in theworld via operational definition. Operational definitions lit-erally point us to concrete indicators of abstract ideas. Forexample, a psychologist might create an operational defini-tion for the abstract construct, hunger, to point to the behav-iors or set of conditions in the world to which hunger is tied.Constructs could also be tied to observations indirectly viaother constructs. In adopting this picture of science, Meehladopted the general positivist misinterpretation of earlyWittgenstein’s philosophy of language according to whichwords are thought to “point to” objects in the world. It is theoperation of ostensive definition where a word stands for anobject and a construct stands for certain pointing procedures.We suspect that there is a kind of Platonism underlyingMeehl’s view of science, where there is a world behind theworld, and that world behind the world is more perfect andmore ordered. In Platonic fashion, the aim of scientific psy-chology is to understand the world behind the world, and theparallel to the notion of latent constructs should be obvious.

We believe this picture has led to all kinds of mischiefin soft psychology because it licenses all manner of con-struct proliferation with the presumed constraint and safetyof eventual steps back to the observational.Meehl (1978)seems to be saying that the lack of progress in soft psychol-ogy would be improved if we could adopt better means ofeliminating or corroborating constructs. We think the prob-lem is best resolved by preventing constructs, at least as pre-

0962-1849/$ – see front matter © 2004 Elsevier Ltd. All rights reserved.doi:10.1016/j.appsy.2004.02.007

46 A.C. Houts, S. Baldwin / Applied & Preventive Psychology 11 (2004) 45–46

sented in Meehl’s view of science, from being introducedin the first place. Once the construct Trojan horse is insidethe gates, the game is over. Psychology may best progressby reconsidering the very notion of constructs rather thantweaking the construct status quo.

To illustrate what we mean, we review briefly the differ-ence between operational definition and operational anal-ysis. Operational definition leads to construct proliferationand operational analysis leads to minimal use of constructsor at least to a “this world” (non Platonic) constraint on theirsignificance. By a circuitous route, Bridgman’s operationalanalysis got turned into operational definition in psychol-ogy. If fact, Bridgman had no such thing in mind and de-plored the use of his name for what turned into operationaldefinition ala Stevens and Boring (Houts, 1994).

Bridgman advocated what he called the operational atti-tude according to which the meaning of a term was to befound by watching the user of the term to find out what ac-tions and conditions were associated with the user speakingthe term. Terms were about activities of scientists and notabout properties of either visible or Platonic objects. A fa-vorite example of his was length 1 versus length 2. Length1 was tactual length; literally the operation of laying downa fixed rod and counting the number of times it was laiddown from point A to point B. Length 2 was optical lengthor the practice of triangulating light beams while also estab-lishing coincidence or simultaneity with clocks. In length 2,the relative motion of the observer and the object of trian-gulation affected the result so that at high velocities lengthcontraction occurred. What Einstein’s special theory of rel-ativity showed was that length is not an enduring immutableproperty of objects but is instead the name we give to cer-tain things we do in relationship to objects. There is no oneenduring construct of length but several quite different con-structs. It so happens that length 1 can always be renderedas length 2 and only under some conditions vice versa. Thefact that the community of physicists can come to have twotypes of length means that length is not immutable and issubject to change as in fact happened. This does not meanthat length is arbitrary but it does mean that length as a con-cept is constrained by practice in the physics community.When it is permissible to use the word length, or any otherphysics concept, is controlled socially in the training andeducation of physicists and also through publication outlets.

That relative constraint observed in physics can be con-trasted with psychology and the way psychology uses con-structs. Diagnosis in psychopathology is one area that hasshown rapid construct proliferation over the past 25 yearswith many new diagnoses introduced and older ones splitup into multiple subtypes of disorders(Baldwin, Williams,Houts, in press; Houts, 2000, 2002). Consider the exam-ple of Post Traumatic Stress Disorder (PTSD). Editions ofthe Diagnostic and Statistical Manuals of Mental Disorders(DSMs) provided varying operational definitions for PTSD.These variations were based on consensus committee deci-sions more often than on performance measurement criteria,

although some consideration was given the latter. In additionto PTSD as defined by the DSMs, there is PTSD as definedby researchers and various treatment purveyors. Even if oneignores the popular press and non mental health professionalcommunities, the occasions for the use of PTSD within themental health professions are legion. What began as a verynarrow Vietnam War related set of complaints noted by twopsychodynamic psychiatrists mushroomed within 20 yearsinto a virtual pandemic talked about by all manner of mentalhealth professionals. Psychologists expanded the contextsin which it is appropriate to use the construct PTSD. Con-sequently, operational definition was expanded to meet thedemands of usage as has been evident in the ever looser cri-teria from DSM-III to the present.

This type of expansion does not generally happen in sci-ences such as physics where equally strange sounding termsmay come into use, e.g., flavor and charm of particles. Abig difference between physics and soft psychology is bestunderstood not by focusing on which discipline uses con-structs but by focusing on operational analysis. When physi-cists use a term like charm or flavor to refer to properties ofsubatomic particles, they are using those terms only undervery precise conditions and they do not permit those termsto be misused by others in the physics community. In con-trast, when clinical psychologists use terms such as PTSD,all manner of conditions can serve as occasions for the useof the term. PTSD can be defined by any number of cutscores on any number of self report instruments, observerchecklists, and physiological measures. Further, PTSD canbe used as a reified entity that somehow causes the symptomsfrom which its very existence is inferred. The difference be-tween hard science and soft psychology is not so much inthe subject matter as in the verbal behavior and the extentto which that verbal behavior is restricted or left uncheckedby the scientific community. Physicists do not let physiciststalk nonsense. Psychology knows no such rudeness and isfar more polite, warm, and fuzzy.

References

Baldwin, S. A., Williams, D. C., & Houts, A. C. (in press). The creation,expansion, and embodiment of posttraumatic stress disorder: A casestudy in historical critical psychopathology.Scientific Review of MentalHealth Practice, in press.

Houts, A. C. (1994). Operational analysis, behavior analysis, and epis-temology in science and technology studies.Mexican Journal of Be-havior Analysis, 20, 101–143.

Houts, A. C. (2000). Fifty years of psychiatric nomenclature: reflections onthe 1943 War Department Technical Bulletin, Medical 203a.Journalof Clinical Psychology, 56(7), 935–967.

Houts, A. C. (2002). Discovery, invention, and the expansion of themodern diagnostic and statistical manuals of mental disorders. In L.E. Beutler & M. Malik (Eds.),Rethinking the DSM: A psychologicalperspective(pp. 17–65). Washington, DC: American PsychologicalAssociation.

Meehl, P. E. (1978). Theoretical risks and tabular asterisks: Sir Karl,Sir Ronald, and the slow progress of soft psychology.Journal ofConsulting& Clinical Psychology, 46, 806–834.