Abstract

The book examines the evolution and significance of operationism in psychology, asserting that a thorough analysis of this concept can address crucial epistemological questions concerning the relationship between experimental practices and concept formation. The book begins by situating its approach within existing discussions about the philosophy of science in practice and integrated HPS (Introduction). It then delves into the historical roots of operationism, focusing on key figures such as S.S. Stevens, E. Tolman, and C. Hull. It argues that operationism emerged not as a semantic theory but as a methodological approach aimed at providing precise, albeit revisable, experimental conditions for the application of psychological concepts (chapter I). Subsequently, the book follows debates about operationism through the early 1960s, pointing out that psychologists were well aware of problems with earlier formulations of operationism and proposed methodological solutions to them (chapter II). The book then shifts attention to more recent psychological research, arguing that operational definitions function as tools for investigating psychological objects of research (chapter III). It then turns to a more thorough analysis of the notion of an object of research, characterizing such objects as “epistemically blurry” (chapter IV). The following chapters explains that objects of psychological research are best understood as clusters of phenomena (V), propose an original account of psychological kinds (VI), and provides a novel analysis of the exploration of the shape of such kinds (VII). The final chapter (VIII) discusses philosophical and methodological implications of the book’s analysis as they pertain to the replication crisis.