If a human subject knows they are being measured, this knowledge may affect their attitudes and behaviour to such an extent that it affects the measurement results as well. This broad range of effects is shared under the term ‘reactivity’. Although reactivity is often seen by methodologists as a problem to overcome, in this paper I argue that some quite extreme reactive changes may be legitimate, as long as we are measuring phenomena that are not simple biological regularities. Legitimate reactivity (...) is reactivity which does not undermine the accuracy of a measure; I show that if such reactivity were corrected for, this would unjustifiably ignore the authority of the research subject. Applying this argument to the measurement of depression, I show that under the most commonly accepted models of depression there is room for legitimate reactivity. In the first part of the paper, I provide an inventory of the different types of reactivity that exist in the literature, as well as the different types of phenomena that one could measure. In the second part, I apply my argument to the measurement of depression with the PHQ-9 survey. I argue that depending on what kind of phenomenon we consider depression to be, we will accept different kinds of reactivity. I show that both under the harmful dysfunction model and the practical kinds model, certain reactive changes in measuring depression are best seen as legitimate recharacterizations of the underlying phenomenon, and define what legitimate means in this context. I conclude that in both models, biological aspects constrain characterization, but the models are not so strict that only one concept is acceptable, leaving room for reactivity. (shrink)

Jonathan Y. Tsou examines and defends positions on central issues in philosophy of psychiatry. The positions defended assume a naturalistic and realist perspective and are framed against skeptical perspectives on biological psychiatry. Issues addressed include the reality of mental disorders; mechanistic and disease explanations of abnormal behavior; definitions of mental disorder; natural and artificial kinds in psychiatry; biological essentialism and the projectability of psychiatric categories; looping effects and the stability of mental disorders; psychiatric classification; and the validity of the DSM's (...) diagnostic categories. The main argument defended by Tsou is that genuine mental disorders are biological kinds with harmful effects. This argument opposes the dogma that mental disorders are necessarily diseases that result from biological dysfunction. Tsou contends that the broader ideal of biological kinds offers a more promising and empirically ascertainable naturalistic standard for assessing the reality of mental disorders and the validity of psychiatric categories. (shrink)

This chapter examines the status of psychopathy as a scientific kind. I argue that the debate on the question whether psychopathy is a scientific kind as it is conducted at present (i.e., by asking whether psychopathy is a natural kind), is misguided. It relies too much on traditional philosophical views of what natural kinds (or: legitimate scientific kinds) are and how such kinds perform epistemic roles in the sciences. The paper introduces an alternative approach to the question what scientific (or: (...) natural) kinds are. On this alternative approach, the Grounded Functionality Account of natural kinds, psychopathy emerges as a “good” scientific kind that is best understood as a region on a multidimensional space of behaviors rather than as a traditional natural kind. (shrink)