Psychiatric disorders as an imperfect community: interview with Peter Zachar, PhD.

This interview with Peter Zachar, PhD, discusses his 2014 book 'A Metaphysics of Psychopathology', and explores his application of the philosophy of scientifically-inspired pragmatism to psychiatric classification, his critique of essentialistic thinking in psychiatry, and his notion of the imperfect community model with regards to psychiatric disorders. The imperfect community is a non-essentialist idea, namely, that the various members of the class of psychiatric disorders have many things in common, but there is no one thing (an essence) that they all have in common that distinguishes them as a group from non-disorders. The resulting domain is, however, not random or arbitrary - new constructs have been introduced for reasons that reflect our scientific goals and pragmatic interests. Zachar is sceptical about the possibility of a single correct and privileged psychiatric classification, but he recognises that the ways in which psychiatric symptoms empirically cluster together places constraints on psychiatric classification that, for instance, don't apply to organising libraries. Classifications are contingent on multiple factors, including our scientific knowledge and goals. Epistemic and evaluative commitments, once identified, work together in a non-arbitrary way to constrain what counts as a good solution to the question of classification.