Evidence, Ontology, And Psychological Science: The Lesson .

Journal of Theoretical and Philosophical Psychology2010, Vol. 30, No. 1, 51– 65 2010 American Psychological Association1068-8471/10/ 12.00 DOI: 10.1037/a0016665Evidence, Ontology, and Psychological Science: The Lessonof HypnosisBrian R. VandenbergUniversity of Missouri, St. LouisData are never free of philosophical encumbrances. Nevertheless, philosophical issuesare often considered peripheral to method and evidence. Historical perspectives likewise are not considered integral to most data-driven disputes in contemporary psychological science. This paper examines the history of the investigation of hypnosis overthe last 75 years to illuminate how evidence and method are entangled with epistemology and ontology, how new research directions are forged by changes in thecultural and philosophical landscape, and how unacknowledged philosophical assumptions can result in confusion and empirical cul-de-sacs. Theoretical disputes that appearto be simple empirical matters often entail hidden philosophical issues, and apparenthistorical continuity at the theoretical level can belie discontinuity at the ontologicallevel. The lesson of hypnosis is that philosophical analysis is as important as methodological rigor.Keywords: hypnosis, history, philosophy of science, constructs, ontologyNot all disputes in psychological science areempirical matters—many entail philosophicalentanglements and confusions. Unfortunately,the training of most scientific practitioners isheavy in method and fact and dismissive ofphilosophical analyses, resulting in continuedcalls for more data, better methods, and yetmore again, while the philosophical issues animating disputes remain unexamined (Slife,1997). Most reviews of the literature underscorethis blinkered view, focusing on recent methodsand findings and concluding with suggestionsfor future research. Rarely are disputes aboutdata considered in concert with philosophicalassumptions. Furthermore, the historical horizon of most reviews is only one or two decades,presuming that prior research is obsolete. Thereasons for obsolescence, however, are oftennot factual inaccuracy, but changes in basicepistemological and ontological assumptionsthat, in turn, are related to significant alterationsin the cultural context. The exclusive focus ondata and the foreshortened historical perspec-tive render such changes and influences invisible. Empirical evidence is but one facet in theadvancement of psychological science for, indeed, the very ground of what constitutes legitimate scientific evidence continues to shift.One way, then, to expose the importance ofthese issues is to examine a particularly enigmatic phenomenon that has incited scientificdebate for decades, if not centuries. Such aphenomenon would enable a broader vision ofthe changing criteria for legitimate scientificevidence, the cultural factors related to thesechanges, and the types of problems that canarise when fact is not considered alongside philosophy. Hypnosis is such a phenomenon. Hypnosis is one of the most provocatively generative topics in the history of psychology, givingrise to psychotherapy, personality theories, formulations of unconscious processes, and appreciation of the power of suggestion and socialinfluence. It has befuddled investigators forover two centuries, and continues to do so(Gauld, 1992). This paper selectively reviewsthe history of hypnosis over the past 75 years toilluminate how evidence and method are entangled with epistemology and ontology, how newresearch directions are forged by changes in thecultural and philosophical landscape, and howdisputes about evidence uniformed by philosophical analysis can give rise to empirical co-Brian R. Vandenberg, Psychology Department, University of Missouri, St. Louis.Correspondence concerning this article should be addressedto Brian R. Vandenberg, 1 University Boulevard, Universityof Missouri-St. Louis, St. Louis, MO 63121. E-mail:bvanden@umsl.edu51

52VANDENBERGnundrums. Three historical epochs will be examined: Hullian behaviorism and World War II;postwar disputes about the validity of hypnosis;and neuroscience and the future.Behavior to ConstructsThe investigation of hypnosis in the 19thcentury was conducted by physicians who usedcase studies to ascertain its effects on patientssuffering from some illness or malady. Duringthis time, the explanation for hypnotic effectsmoved from an external force, “animal magnetism” at the beginning of the century; to internalbiological causes, neural disruption, and hysteria, by mid to late century; to psychologicalfactors, unconscious processes, and suggestion,by the end of the century. These last explanations proved to be an ontological watershed, asphysical, biological, and medically based entities, rooted within a scientifically establishedexplanatory framework, were superseded bypsychological phenomenon, which was not.Psychological explanations of hypnosis haveprevailed throughout the 20th century, but whatconstitutes legitimate scientific explanationwithin this domain has been the source of continued, often acrimonious dispute. Indeed, at thebeginning of the 20th century, when psychosocial replaced biomedical explanations, the scientific status of these explanations was deeplyproblematic. Even Janet (1925), a pioneer inforging one of the leading psychological theories of hypnosis, had this to say about his ownefforts:All this (psychological) formulation seemed simultaneously true and void. It seemed superficial and notreally scientific . . . psychology was not favorably regarded by the leaders of the medical profession, whoremembered that they had heard vague talk on thesubject in the later days of school life, and who fanciedthat it was a mishmash of literature and ethics (p. 205).Janet’s doubts may echo others in the biomedical sciences, who throughout the 20th century,ignored or eschewed the topic of hypnosis.The doubts about the scientific viability ofpsychology in the first decades of the 20th century gave impetus to the rise of behaviorism,which was based on a positivistic philosophy ofscience, utilized methods that focused on overt,observable behavior, and banished all references to internal, mental phenomenon (e.g.,Watson, 1913). Consequently, the study of hyp-nosis, with its mentalistic explanations andmystical associations, was greatly diminished(Gauld, 1992). Hypnosis, if it was to reemergeas topic of scientific inquiry, would have to berepositioned within this new epistemologicaland methodological context.Behaviorism and HullHull’s (1933) remarkable book, Hypnosisand Suggestibility repositioned the study ofhypnosis. The conclusion offered, that hypnosisderives from suggestion, is not new, but theargumentation is unlike anything published onthe topic prior to the 20th century. Whereas theevidential base for the study of hypnosis in the19th century was case studies of individualswith medical disorders, Hull described the results of a series of experiments with nonclinicalpopulations whose reactions were quantitativelymeasured, sometimes through cleverly designedinstruments that, for example, recorded minutebodily sway, and the evidence was presented intables and graphs. Those given hypnotic induction are compared to controls who were giventhe same suggestions in a normal waking condition, so that the true effects of hypnosis, ifany, could be unambiguously detected. Hull’sinvestigations led him to reject many assumptions associated with hypnosis. It is not sleep;rapport plays no role; it is not hysteria; it is notdissociation; there is no increased sensitivity toweak stimuli. The only difference between hypnotized and control groups is increased susceptibility to suggestion in the hypnosis condition,which Hull argued was likely due to increasedmuscle relaxation that accompanies hypnoticinduction. The state of hypnosis, if it can becalled that, is simply a quantitative change insusceptibility.Hull (1933) also offered a detailed explanation of the mechanisms of hypnotic suggestion,which is achieved by short-circuiting the process responsible for voluntary control of behavior. Volition, he argued, results from “activeintraorganic symbolic sequences” (p. 396) thatlead to subvocal speech, which acts as a selfdirected command, evoking action. Hypnoticinduction prompts muscle relaxation, attenuating internal symbolic activity, allowing the vocalizations of the hypnotist to be passively accepted, triggering the suggested activity. Earliertheorists often used ideomotor action to explain