Modern disorders of vitality: the struggle for legitimate incapacity.

Subjective incapacity and fatigue are common as secondary symptoms in many physical and psychiatric disorders. In the last decade, however, a range of “new” illnesses has emerged in which incapacity and fatigue are the primary and central complaints. Patients with these illnesses may often be difficult to treat on an individual level. In the public domain, they are very vocal, challenging medical expertise. Patients present with diffuse and unspecific complaints, such as excessive fatigue, muscular aches and pains, and difficulty in concentrating. Embedded in these complaints is a perceived incapacity to perform daily activities in the usual way, so that incapacity becomes an essential and primary characteristic of the illness. As fatigue seems to be the symptom with the closest experiential ties to incapacity, this may be the reason why this symptom figures so prominently in the often excessive lists of complaints of these patients. Although medical examinations reveal no obvious organic explanation, the patients persist in attributing the complaints to a physical cause, either in the body or the environment or both. The legitimacy of the syndromes invoked in (self-)diagnosis is, to varying degrees, debated in medical science as well as in social security and the law. Examples include multiple chemical sensitivity syndrome (MCS), chronic fatigue syndrome (CFS), silicone breast implant-related toxic syndrome, complaints related to dental amalgam, sick building syndrome (SBS), and fibromyalgia (FM) [1, 2]. They are, as yet, not part of the official classifications of diseases. In what follows, we present a conceptual perspective intended to strengthen current attempts at avoiding unproductive mind–body splits in dealing with these illnesses. Some of the difficulties in understanding these new illnesses appear to be a consequence of the currently accepted biomedical model of diseases. This model supposes that there are physical or psychiatric illnesses underlying the incapacity, which are identifiable within a human body or person. An alternative conceptualization of incapacity, not as a secondary consequence of another illness, but a pri-