The Principle of Inversion: Why the Quantitative-Empirical Paradigm Cannot Serve as a Unifying Basis for Psychology as an Academic Discipline

Introduction: In the English-speaking world, as well as in the international academic discourse and many other languages, the term “science” or appropriate translations refer only to a certain area of knowledge, namely the natural and the social sciences, thus excluding what is usually referred to as humanities or Geisteswissenschaften (Szostak, 2004). The history and philosophy of science shows that the sciences rely heavily on the so-called Scientific Method, a set of theoretical and methodological principles which consists, in essence, of observing, formulating hypotheses and testing these hypotheses in experiments, in order to discover general laws. In doing so, knowledge is generated by relying on empirical evidence, which in turn expresses directly observable phenomena in terms of quantitative data. Excluding the extremely complex discussions about advantages, drawbacks, and alternatives to the Scientific Method (e.g., Gower, 1997; Nola and Sankey, 2014; Andersen and Hepburn, 2015), it is important to note that quantitative-empirical methods and thinking according to the Scientific Method dominate the sciences (Haig, 2014; Nola and Sankey, 2014; Sankey, 2014) and also psychology (Garber, 2019; Haig, 2019; Toomela, 2020). By contrast, the humanities rely much less on quantitative—let alone experimental—methods, although these are employed nonetheless when appropriate. Instead of producing and gathering empirical data, the humanities characteristically approach their subject matter from a descriptive, interpretive, and hermeneutical understanding whose historical and comparative angles cannot be conveniently summarized by a single term (Watanabe, 2010; Bem and De Jong, 2013; Leezenberg and De Vries, 2019).