As well as its youth, the new philosophy of psychiatry has two further features that make it stand out. Firstly, it is not a 'natural kind'. There is not an established set of inter-related problems with familiar, if rival, solutions. It is an area where philosophical methods, accounts and theories can be applied to psychiatric phenomena and thus it also serves to test those accounts. To take one type of example, psychopathology is a test track for theories in the philosophy of mind. Symptoms such as thought insertion, where subjects experience their thoughts as somehow not their own, challenge accounts of the everyday 'ownership' of thoughts. But there is also traffic the other way. Three centuries of discussing the relationship of mind and body have furnished philosophers with a variety of subtle models (from forms of dualism, through gradations of physicalism, to eliminativism with modern alternatives such as enactivism) which can help in the interpretation of psychiatric data.
Secondly, unlike some areas of philosophy, philosophy of psychiatry can have a genuine impact on practice. It is a philosophy of, and for, mental health care. It provides tools for critical understanding of contemporary practices, and of the assumptions on which mental health care more broadly, and psychiatry more narrowly, are based. Thus it is not merely an abstract area of thought and research, of interest only to academics. In providing a deeper, clearer understanding of the concepts, principles and values inherent in everyday thinking about mental health, psychiatric diagnoses and the theoretical drivers of mental health policy, it can impact directly on the lives of people involved in all aspects of mental health care.
Values, meanings, facts
A brief examination of the history of the subject reveals why the discipline of psychiatry is particularly suited to contributions from philosophy. Whilst the father of psychopathology, the German philosopher and psychiatrist Karl Jaspers, combined psychiatric and philosophical expertise, within the English speaking tradition philosophy and psychiatry went their separate ways throughout most of the twentieth century. (By contrast, in mainland Europe the connection between psychiatry and phenomenological philosophy has continued since Jaspers' day.)
But towards the end of the twentieth century, the rise of the anti-psychiatry movement prompted a resurgence of philosophical interest in psychiatry. This was because a key element of the anti-psychiatric criticism of mental health care turned on a contentious claim about the nature of mental illness: mental illness does not exist; it is a myth. Such a sceptical claim is paradigmatically philosophical and one of the main proponents of anti-psychiatry, the psychiatrist Thomas Szasz, put forward a number of philosophical arguments in support of it. These turned on the fact that psychiatric diagnosis is essentially evaluative. From this he concluded that, unlike physical illness, it could not be medically treated because as illness it was not real. (The apparent reality of mental illness is best explained, according to Szasz, as the reality of non-medically treatable life problems.)
Szasz's sceptical arguments spurred responses by both psychiatrists and philosophers questioning whether diagnosis is, after all, essentially evaluative and, if it is, whether Szasz's conclusions followed. Thus the analysis of mental illness, and the role of values in that analysis, lies at the heart of recent philosophy of psychiatry.
In addition to the importance of values, two further key areas of mental health care prompt immediate philosophical questioning. Firstly, psychiatry since Jaspers has sought to balance two key elements: investigation of the bio-medical facts and empathic investigation of subjects' experiences. Both bio-medical facts and meanings (broadly construed to include experiences, beliefs and utterances) need somehow to be integrated into mental health care. This marks a sharp delineation from other areas of medicine where subjects' experiences are subordinate to the physically described symptoms and organic pathology with which they present. By contrast, psychiatric disorders seem to involve problems of the 'self' (however this is construed) in which experiences, behaviour and beliefs play a fundamentally important role in the onset, course and recovery of symptoms.
This raises questions of both the nature of the distinction between explanation according to the canons of the natural sciences (the 'realm of law') and understanding meaningful connections (in the 'space of reasons') and the relationship between natural scientific facts and meanings. If there is a clear distinction and meanings are conceptually irreducible to biomedical facts, efforts to understand the nature of this relationship become all the more philosophically interesting.
Secondly, there has been much work by psychiatrists since the Second World War to develop psychiatric classification or taxonomy. This has, historically, been in response to a concern about a lack of agreement or reliability about psychiatric diagnosis. More recently, there has been growing concern that reliability has been improved but only at the cost of validity, or underlying truth, of classificatory schemas. The worry is that psychiatric diagnostic systems may not 'carve nature at the joints'. This concern has also been reflected in philosophy of psychiatry as an instance of a broader question of the role of science in mental health care. Thus the nature of the facts in question is still very much up for grabs.