An eighteenth-century medical-meteorological society in the Netherlands: an investigation of early organization, instrumentation and quantification. Part 2.

Scholarship has offered a range of judgements of the Correspondentie Sociëteit. In their recent study of the Netherlands at the start of the nineteenth century, Joost Kloek and Wijnand Mijnhardt characterize the efforts of the Correspondentie Sociëteit as a 'temporary milestone' in 'medical involvement with society'. According to them, this involvement arose after 1750, after university-trained medical doctors had reoriented themselves towards empiricism as a working method. They claim that this resulted in a preventative medical programme starting in about 1770; this process made a significant contribution to increased professional feeling and professional respect of the medical class. Far more negative in his assessment was Harry Snelders, who in 1981 conducted a general investigation of the Verhandelingen of the Correspondentie Sociëteit. He concluded that 'in the end the Sociëteit left us with little more than many particulars about the number of births and deaths in many places in the country, which illnesses people died from, some meteorological observations and an overview of the many contributors'. Also rather negative in his judgement was Frank Huisman, who in 1997 investigated the medical records of the Groningen section of the Correspondentie Sociëteit. Although Huisman underlined the importance of the Correspondentie Sociëteit in the process of the emancipation of the medical class, he also concluded that in the medical field scarcely any insight had been obtained into dominant illnesses. According to Huisman, the medical publications of the Correspondentie Sociëteit 'do not contain an expected level of abstraction, on the contrary they were very casuistic and contained many lists without any form of interpretation'. He judged that the medical doctors of the Correspondentie Sociëteit were no more than 'defective empiricists', because they never explicitly explained the transition from empirical material to theory. In Huisman's opinion, 'the correctness of the ideas adopted was indisputable, so that measurements could never have led to a modification, let alone a rejection, of the theory'. The question arises as to whether this is a useful way of making historical judgements. From a historical viewpoint, processes and efforts rather than results are most important, and innovations with respect to the institution's contemporary practices are to be assessed. If the Correspondentie Sociëteit is examined from such a perspective, then the result is rather positive, at least for the society's meteorological aspect. In the meteorological section of the Verhandelingen attention was mostly devoted to the set-up, methodology and recording of observations. This is hardly surprising, because in this field organized and systematic work was something very new in the Netherlands; members of the Correspondentie Sociëteit had to discover this effectively at first hand. There was no previous expertise on which to rely. The Correspondentie Sociëteit was the first in the Netherlands to genuinely organize scientific research. Moreover, contributors to the society performed much work. During a period of just over ten years the society published eleven volumes with almost five thousand pages of printed observations, about one-third of which was concerned with meteorology. Although these volumes were indeed partly descriptive, this does not mean that a higher level of abstraction was not the aim. For example, in his report about the weather during the years from 1779 to 1781, Van der Weyde sought to draw thoroughly analytical conclusions and even provided methodological arguments. According to Van der Weyde, the body of knowledge formed 'one large structure' which would only progress when many investigators worked on it together. Various types of natural knowledge needed to be distinguished. Meteorological knowledge could only be deduced from observation. Van der Weyde held that reliable natural knowledge was generated in three stages: first, collection and description of the phenomena; then the more difficult step of deriving inferences or patterns from these observations; the third step, the most difficult, to find an underlying theory or explanation. This step could only be taken after much preliminary work had been done. Van der Weyde considered Van Swinden's work on the magnetic needle to be an example of the first phase, that of describing phenomena. An example of the second phase, the derivation of inferences, was