Rules of Conduct for Behavior Analysts in the Presence of Hypothetical Constructs: A Commentary on Eckard and Lattal (2020)

A Correction to this article was published on 10 December 2020

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Eckard and Lattal (2020) summarized the behavioristic view of hypothetical constructs and theories, and then, in a novel and timely manner, applied this view to a critique of internal clock models of temporal control. In our three-part commentary, we aim to contribute to the authors’ discussion by first expanding upon their view of the positive contributions afforded by constructs and theories. We then refine and question their view of the perils of reifying constructs and assigning them causal properties. Finally, we suggest to behavior analysts four rules of conduct for dealing with mediational theories: tolerate constructs proposed with sufficient reason; consider them seriously, both empirically and conceptually; develop alternative, behavior-analytic models with overlapping empirical domains; and contrast the various models. Through variation and selection, behavioral science will evolve.

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  • 10 December 2020

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  1. 1.

    Timing, time perception, temporal regulation, and temporal discrimination are alternative labels to designate approximately the same research domain.

  2. 2.

    “These drawbacks center on very practical concerns for psychology as an experimental and theoretical enterprise” (p. 11; emphasis added).

  3. 3.

    Their rationale is similar to behavioral-analytic research by Dews (1970) who turned on and off the keylight to study whether pigeons’ temporal performance in a FI schedule was chain-like, in which case it should be disrupted by the stimulus interruptions.

  4. 4.

    The argument seems to imply that theoretical entities and therefore theories are dispensable; hence the theoretician’s dilemma.

  5. 5.

    Cognitive researcher Johnson-Laird (1988) gave two answers to the theoretician's dilemma, both intended as a criticism of the behavioral approach: (1) Much of human behavior is spontaneous in the sense that it does not depend on external causes, and (2) granted that mental states exist, we should study them even if they are not necessary to formulate the laws of behavior. Point (1) is questionable because spontaneity does not imply lack of sensitivity to context; point (2), however, is well taken, but by the same token we can conclude that, if mental states have a historical origins then we should study them, even though that origin may not be necessary to formulate the laws of cognition.

  6. 6.

    To avoid mediational models, behaviorists could take the scalar property as a theoretical primitive and relegate to neuroscience the explication of its physiological basis. They could also elaborate the notion of generic stimulus and response class to encompass statistical classes, and then assume that stimulus duration would form statistical classes obeying Weber’s law. As Zuriff (1985) noted, mediation would be avoided by functionally (re)defined stimulus and response classes, the invariants of the learning episode (Machado, 1992, 1993).

  7. 7.

    In his 1615 essay "Letter to the Grand Duchess Christina," Galileo tries to reconcile the Copernican system with the doctrines of the Church. One of his famous remarks concerned scriptural interpretation: “Hence I should think it would be the part of prudence not to permit anyone to usurp scriptural texts and force them in some way to maintain any physical conclusion to be true [or false], when at some future time the senses and demonstrative or necessary reasons may show the contrary” (Galileo Galilei, 1957/1615, p. 187). Likewise, behavioral analysts should not reject or deny hypothetical constructs that might, upon further research, prove useful and true.


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Armando Machado is a member of the William James Center for Research supported by the Portuguese Foundation for Science and Technology. Armando Machado and Marcelo S. Caetano are members of the Instituto Nacional de Ciência e Tecnologia sobre Comportamento, Cognição e Ensino, supported by the Brazilian National Research Council (CNPq, Grant # 465686/2014-1), the Coordination of Superior Level Staff Improvement (CAPES, Grant # 88887.136407/2017-00), and the São Paulo Research Foundation (FAPESP, Grant # 2014/50909-8). PG would like to thank Dr. Robert F. Littleton for his ongoing support.

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The acknowledgement section was updated in the original article to include the sentence “PG would like to thank Dr. Robert F. Littleton for his ongoing support”.The acknowledgement section was updated in the original article to include the sentence “PG would like to thank Dr. Robert F. Littleton for his ongoing support”.

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Machado, A., Guilhardi, P., Caetano, M.S. et al. Rules of Conduct for Behavior Analysts in the Presence of Hypothetical Constructs: A Commentary on Eckard and Lattal (2020). Perspect Behav Sci 43, 791–802 (2020).

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  • Behavior analysis
  • Hypothetical constructs
  • Internal clock models
  • Mediational theories
  • Temporal control