Fundamentals of clinical methodology: 3. Nosology

Intelligent clinical judgement is one of the main goals of medical artificial intelligence. To achieve that goal requires a reliable nosological language. Such a language is not yet available, however. In this paper the notions of health, disease, and nosology are analyzed. It is shown that health and disease as generic concepts, and also individual disease entities are best understood as fuzzy sets. Clinical language and linguistics, nosology and diagnosis may thus become directly amenable to fuzzy theory.