Skip to main content

The Definition of Mental Disorder: Evolving but Dysfunctional?


Natalie Banner
I'm a former research fellow in the philosophy of psychiatry at King’s College London, now working in policy at the Wellcome Trust. In my academic research the definition of mental disorder was a frequent, seemingly intractable problem and in this post I want to query whether a definition may be needed at all.

In a previous post, Rachel Cooper talked about the potential advantages of the ambiguity offered by the DSM-5 definition of mental disorder. I very much agree that the stipulation of necessary and sufficient conditions is unlikely to succeed in mapping such complex messy and controversial phenomena as “mental disorders”. However, I am unsure whether in this particular case an ambiguous definition is quite so benign as Rachel implies. It is true that few clinicians will pay attention to the introductory text, being more concerned with the features of the diagnosis they are dealing with at any particular moment, but this is not to say that the definition provided is not an important and influential part of the manual.


As a colleague Rachel Bingham and I suggested in a recent paper, a significant driver for attempting to define mental disorder emerged in the scientific and political fallout of the declassification of homosexuality from the DSM in 1973. The move to declassify came about through civil rights activism that highlighted, among other things, the lack of scientifically credible evidence to support the claim that homosexuality was a mental disorder: psychodynamically-driven theories assuming the pathological status of homosexuality were undermined once the existence of happy, functioning, well-adjusted gay individuals was acknowledged. Against this backdrop, it is understandable why the effort to seek out a clear cut definition of mental disorder, and thus clarify the domain of psychiatry, was so important. If psychiatry was to avoid being used as a tool of social control to pathologise behaviours simply seen as abnormal by society, it had better be able to delineate what counts as a mental disorder from what doesn’t.

Fast forward to today, and the DSM-5 definition attempts to bridge the ‘values-out’ versus ‘values-in’ camps with a broad definition subject to wide interpretation. This has its uses when the jury is still out, certainly, but we ought to be alert to the potential dangers of ambiguity in the wording of any working definition that is supported by the influential DSM. This is particularly so given concerns over the inflation of psychiatric categories and the perceived risks of pathologising what are essentially normal human behaviours. Only last month the diagnosis of Attention Deficit Hyperactivity Disorder was called into question by a leader in the field, and there has long been controversy over whether the DSM-5 criteria count the experience of bereavement as “major depression.” Sensible discretion in the application of the definition may be urged (akin to Rachel’s example from HLA Hart), but there are many competing interests at stake in diagnostic classification that may not in practice reflect the deliberations of a objective, dispassionate and sensible judge.

If one of the reasons for seeking a definition of mental disorder in the first place was to prevent psychiatry from over-reaching its boundaries, I’d argue that it could be better not to attempt to define the overarching category of “mental disorder” at all. This would be preferable to providing a scientific gloss to ambiguous terms that could potentially encompass far more behaviours, conditions and experiences than the authors of the definition ever intended.

Popular posts from this blog

Delusions in the DSM 5

This post is by Lisa Bortolotti. How has the definition of delusions changed in the DSM 5? Here are some first impressions. In the DSM-IV (Glossary) delusions were defined as follows: Delusion. A false belief based on incorrect inference about external reality that is firmly sustained despite what almost everyone else believes and despite what constitutes incontrovertible and obvious proof or evidence to the contrary. The belief is not one ordinarily accepted by other members of the person's culture or subculture (e.g., it is not an article of religious faith). When a false belief involves a value judgment, it is regarded as a delusion only when the judgment is so extreme as to defy credibility.

Rationalization: Why your intelligence, vigilance and expertise probably don't protect you

Today's post is by Jonathan Ellis , Associate Professor of Philosophy and Director of the Center for Public Philosophy at the University of California, Santa Cruz, and Eric Schwitzgebel , Professor of Philosophy at the University of California, Riverside. This is the first in a two-part contribution on their paper "Rationalization in Moral and Philosophical thought" in Moral Inferences , eds. J. F. Bonnefon and B. Trémolière (Psychology Press, 2017). We’ve all been there. You’re arguing with someone – about politics, or a policy at work, or about whose turn it is to do the dishes – and they keep finding all kinds of self-serving justifications for their view. When one of their arguments is defeated, rather than rethinking their position they just leap to another argument, then maybe another. They’re rationalizing –coming up with convenient defenses for what they want to believe, rather than responding even-handedly to the points you're making. Yo

A co-citation analysis of cross-disciplinarity in the empirically-informed philosophy of mind

Today's post is by  Karen Yan (National Yang Ming Chiao Tung University) on her recent paper (co-authored with Chuan-Ya Liao), " A co-citation analysis of cross-disciplinarity in the empirically-informed philosophy of mind " ( Synthese 2023). Karen Yan What drives us to write this paper is our curiosity about what it means when philosophers of mind claim their works are informed by empirical evidence and how to assess this quality of empirically-informedness. Building on Knobe’s (2015) quantitative metaphilosophical analyses of empirically-informed philosophy of mind (EIPM), we investigated further how empirically-informed philosophers rely on empirical research and what metaphilosophical lessons to draw from our empirical results.  We utilize scientometric tools and categorization analysis to provide an empirically reliable description of EIPM. Our methodological novelty lies in integrating the co-citation analysis tool with the conceptual resources from the philosoph