Psychologists debate whether mental attributes can be quantified or whether they admit only qualitative comparisons of more and less. Their disagreement is not merely terminological, for it bears upon the permissibility of various statistical techniques. This article contributes to the discussion in two stages. First it explains how temperature, which was originally a qualitative concept, came to occupy its position as an unquestionably quantitative concept (§§1–4). Specifically, it lays out the circumstances in which thermometers, which register quantitative (or cardinal) differences, (...) became distinguishable from thermoscopes, which register merely qualitative (or ordinal) differences. I argue that this distinction became possible thanks to the work of Joseph Black, ca. 1760. Second, the article contends that the model implicit in temperature’s quantitative status offers a better way for thinking about the quantitative status of mental attributes than models from measurement theory (§§5–6). (shrink)

In recent decades, there has been widespread debate in the human and social sciences regarding the compatibility and the relative merits of quantitative and qualitative approaches in research. In psychiatry, depending on disciplines and traditions, objects of study can be represented either in words or using two types of mathematization. In the latter case, the use of mathematics in psychiatry is most often only local, as opposed to global as in the case of classical mechanics. Relationships between these objects of (...) study can in turn be explored in three different ways: 1/ by a hermeneutic process, 2/ using statistics, the most frequent method in psychiatric research today, 3/ using equations, i.e. using mathematical relationships that are formal and deterministic. The 3 ways of representing entities (with language, locally with mathematics or globally with mathematics) and the 3 ways of expressing the relationships between entities (using hermeneutics, statistics or equations) can be combined in a cross-tabulation, and nearly all nine combinations can be described using examples. A typology of this nature may be useful in assessing which epistemological perspectives are currently dominant in a constantly evolving field such as psychiatry, and which other perspectives still need to be developed. It also contributes to undermining the overly simplistic and counterproductive beliefs that accompany the assumption of a Manichean “quantitative/qualitative” dichotomy. Systematic examination of this set of typologies could be useful in indicating new directions for future research beyond the quantitative/qualitative divide. (shrink)

Cramer et al.'s critique of latent variables implicitly advocates a type of scientific anti-realism which can be extended to many dispositional constructs in scientific psychology. However, generalizing Cramer et al.'s network model in this way raises concerns about its applicability to psychopathology. The model could be improved by articulating why a given cluster of symptoms should be considered disordered.

Within contemporary personality psychology there is widespread consensus that, at long last, the basic elements of "the" human personality have been empirically discovered, and that the systematic search for the underlying causes and consequences of personality differences can be pursued on this basis. The putatively basic trait dimensions are neuroticism, extraversion, openness, agreeableness, and conscientiousness, and are referred to collectively as "the Big Five." In the present article, this perspective on the psychology of personality is examined critically and found wanting. (...) It is argued that neither the "Big Five" framework in particular nor trait "psychology" more generally is adequate as the basis for a scientific psychology of the human person. 2012 APA, all rights reserved). (shrink)

The so-called "problem of theoretical terms" rests on the notion that the signifiers of theoretical concepts cannot be completely defined for the reason that their referents are beyond the boundaries of human perception and/or cognition. Empirical realism is a scientific tradition that was born, in part, out of a dissatisfaction with the positivist treatment of theoretical terms. Empirical realists generally conceive of theoretical terms as playing an essential role in scientific activity, giving it its explanatory force, as it is such (...) terms which denote the real, but unobservable, hypothetical entities which are thought to underlie those observable phenomena that the scientist seeks to explain. Despite certain consistencies that run throughout realist thought, there also exist a number of points of divergence among empirical realists. These are examined along with 2 different and contrasting traditions of empirical realism within psychological science. 2012 APA, all rights reserved). (shrink)