Abstract
In the February issue of this Journal Jones and Blackshaw [1] argued convincingly for an evolutionary approach to psychiatric disorders. I would like to take the opportunity to remind colleagues of Karl Ludwig Kahlbaum, a 19th century German psychiatrist, commonly known among psychiatrists for the first systematic description of catatonia. 15 April 1999 was the 100th anniversary of Kahlbaum's death. However, his relevance to modern psychiatry has been undervalued with a few exceptions [2,3].
Karl Ludwig Kahlbaum (1828–1899) was born in Driesen, East Germany. As a schoolboy, he was interested in the natural sciences, and attended lectures in chemistry, physics, botany, zoology, including evolutionary theory, at the University of Königsberg. At his father's request, he studied medicine in Würzburg, Leipzig, and Berlin. After his efforts to start an academic career had failed, in part due to his political sympathy for the democratic opposition in Germany, Kahlbaum took over a private hospital in Görlitz in 1867, where he introduced occupational and music therapy, and a ‘medical pedagogium’ for juvenile psychiatric patients [3]. Whereas Kahlbaum's publication on ‘catatonia or the tension insanity’, and on ‘hebephrenia’, written by Ewald Hecker (1871) on behalf of Kahlbaum have been adopted by psychiatry, the heuristic value of Kahlbaum's scientific work is still underrecognised from both the nosological and the methodological perspectives. Although handicapped by a circumstantial writing style, Kahlbaum's book Die Gruppirung der psychischen Krankheiten und die Eintheilung der Seelenstörungen (which could be translated as ‘Grouping of psychiatric diseases and the classification of mental disorders’) based on Carl von Linné's classification of animals and plants is probably his most important contribution [4]. At that time, psychiatry's detachment from romantic concepts had just begun, with the ‘unitary psychosis’ being the prevailing paradigm in psychiatry. Hence, it is all the more remarkable that Kahlbaum challenged the established psychiatric nosology based on an evolutionary perspective only 4 years after Darwin's epoch-making publication On the origin of species by means of natural selection (1859), whose relevance to psychiatric research Kahlbaum mentioned explicitly [4, p. 178]. Kahlbaum's classification of psychiatric disorders, however, has not succeeded, probably because of its incompatibility with the contemporary mainstream and with the conceptual pluralism of later epochs [3]. Because Kahlbaum considered psychiatric disorders to be ‘experimental states provided by nature’ he emphasised what he called the ‘clinical method’ in psychiatry, analogous to the methodology of other natural sciences. The clinical method, Kahlbaum argued, consists of unprejudiced behavioural observation, thorough description and recording of all psychic and somatic phenomena [5]. Further, Kahlbaum's intention was to link the empirically acquired clinical material with neuropathological correlates, an aim which remained unachieved in his time.
However, the clinical method became re-invented in a different scientific field, namely ethology, as a valuable process of data acquisition. Also, psychiatric research has recently attempted to correlate behaviour, subjective experience, neuropathology, while lacking an integrative theory, for example evolutionary epistemology [1]. Yet, heuristic frameworks on how and why human behaviour and the underlying cognitive capacities have evolved as species-specific solution to problems of adaptive significance have recently been elaborated by evolutionary psychologists [6].
It may be said that Karl Ludwig Kahlbaum was ahead of his time in terms of clinical methodology and nosology of psychiatric disorders. We may mark the occasion reviving his ideas on psychiatric research based on evolutionary grounds in order to arrive at a deeper understanding of behaviour-physiology-interactions.