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Hermann von Helmholtz (1821-1894)
als Kulturträger:
Philosophisch-wissenschaftlicher Lebenslauf

87. Veranstaltung der HUMBOLDT-GESELLSCHAFT am 26.06.99 von Patrick McDonald (Gastvortrag)


Das Helmholtzgrab in Berlin-Wannsee

The discussion of Helmholtz at the Sitzung der Humboldt-Gesellschaft fell into roughly three parts. The first concerned the broader context in which Helmholtz worked. The second focused more specifically on the course of Helmholtz's scientific career. The third covered my particular research on Helmholtz's philosophy of science and his research in physiological acoustics. In what follows I follow this rather loosely, but most of the content is provided. Within the broader intellectual context three fields were most important: physics, physiology and philosophy.

In physics, the important trends were the following. The rise of an energy-based as opposed to a force-based physics was a trend to which Helmholtz had contributed, most famously with his treatise "Ueber die Erhaltung der Kraft" in 1847. The principle of energy conservation allowed for the unification of previously disparate fields of phenomena under one disciplinary umbrella, i.e. theoretical and experimental physics. Helmholtz was an important player in the elaboration of the concept of energy and of the field of physics made possible by this conceptual insight. Some of his contributions included work in electricity and magnetism in the 1870s as well as molecular models for thermodynamics in the 1880s as well as important contributions on the principle of least action. He developed a distinctive style of physical research whose combination of experimental methods and theoretical representation had a decisive influence on the next generation of physicists in Germany including Heinrich Hertz, Ludwig Boltzmann, and Max Planck.

The field of physiology had seen a remarkable increase in the sophistication of experimental techniques and mathematical representation. Helmholtz and his young colleagues in the late 1840s and 1850s had inherited a well-developed field of research from Johannes Mueller and Justus Liebig, among others. To this Helmholtz and his friends Emil Du Bois-Reymond, Karl Ludwig and Ernst Bruecke added a more advanced set of mathematical skills and physical techniques transferred from physics and applied to physiological problems. The development of the principle of the conservation of energy provided a powerful tool to analyse physiological processes. There was no longer need to appeal to a special "Lebenskraft" in physiology. Further, Helmholtz had been trained as a physician (Arzt) and this medical background gave him important physiological and anatomical training put to use so effectively in his sensory research (vision and hearing). This research also reveals the trend in the 1850s and 1860s for sensory physiology to be mined as a fertile resource for the emerging field of experimental psychology. Helmholtz may not be seen as the founder of experimental psychology (Gustav Fechner and Wilhelm Wundt are often cited as founders), but he was a very important forerunner.

Finally at the time in which Helmholtz was maturing as a professional, there was a decisive trend in philosophy away from speculative metaphysics in the style of Hegel and Schelling. This can be more or less identified with the "Back to Kant" movement of which Helmholtz was an important member. Philosophy was re-conceived by some of the members of this movement as primarily Erkenntnistheorie. In any case this represents what Helmholtz saw as the primary task of philosophy and ist essential importance for the foundations of science. I should note as well that because of the dramatic advances in science there was much discussion of materialism in philosophy. It is important to note that Helmholtz was very careful to distance himself from this trend, if for no other reason than the fact that materialism engaged in the kind of metaphysical speculation that he saw as a hindrance to the advance of scientific knowledge. I discussed briefly a few central issues in the Philosophy of Science. The general aim of science is a leading issue. Here is addressed the question of what kinds of explanation science attempts to provide as well as the limits of science and the distinction between science and non-science. A different but related theme is the nature of scientific theories, their structure and their historical character. The relation between scientific theory and experiments has played an important role, and continues now in a lively discussion under the name of "New Experimentalist" philosophy of science. This movement concerns itself with exploring the theory independent nature of much experimental research and the particular structure of experimental arguments.

My approach to Helmholtz attempts to incorporate some of these "experimental" themes. Finally much debate in the philosophy of science for the past 30 years or so has centered around the degree to which scientific knowledge genuinely reflects the essence of nature, or whether it works as a practical tool, that while effective, has no pretensions of being literally "true". In this spirit, many question the warrant we have to infer the existence of unobservable entities such as quarks, ecosystems, black holes and the like.

Helmholtz had a very productive scientific career as well as a fulfilling cultural life. He was born 31.August. 1821 in Potsdam. He entered the Potsdam Gymnasium at the age of 8 (1830) and then into medical studies in the Friedrich Wilhelm Institut-Berlin in 1838. In August of 1847 he delivered the lecture "Ueber die Erhaltung der Kraft" (in Berlin), which had a major impact upon the fields of physics, physiology and philosophy. In 1849 he was appointed Ausserordentliche Professor of physiology in Koenigsberg, and married Olga von Velten (1826 - 1859). Their first child Katharin was born the next year. That year as well, Helmholtz invented the Augenspiegel. In 1855 he delivered the Kant-Denkmal lecture in Koenigsberg, "Ueber das Sehen des Menschen" which many cite as an influential contribution to the formation of neo-Kantian philosophy. In any case, it was a very important early formulation of his philosophy of perception. Within the next 12 years Helmholtz would publish two monumental works in the sciences of perception: the "Handbuch der physiologischen Optik", and "Die Lehre von den Tonempfindungen als physiologische Grundlange fuer die Theorie der Musik". These works were particularly important for at least three reasons:

They brought together in one point of view many disparate sub-fields in vision and hearing research. Thus they acted as important syntheses. Two, they developed the mathematical, physical, and experimental techniques of the sciences of the senses in unprecendented depth. Third these works cemented a methodological viewpoint, combining the resources of physics, physiology and psychology, that endures to this day.

The bulk of the work contained in these volumes was carried out in Bonn, where Helmholtz moved in 1855, and then in Heidelberg where he worked from 1858 until 1871. 1859 was a difficult year for Helmholtz. Both his father, with whom he was quite close, and his wife Olga passed away. For a number of reasons, Helmholtz felt compelled to marry again soon (he had small children) and in 1861 he marred Anna von Mohl (1834-1899). She was the daughter of a Heidelberg Professor, well-educated socially connected. She played a very important role in extending Helmholtz's social circle. In 1871 he achieved a life-long ambition and was appointed to the chair of physics in Berlin. Here he published important studies in electrodynamics and influenced a generation of physicists that changed the face of physics. He gave a Stiftungsfeier address in 1878 at the University in Berlin entitled "Die Thatsachen in der Wahrnehmung". This was very possibly his most important philosophical work and ranges over many of the epistemological issues central to his work. In 1888 he was appointed the first President of the Physikalisch-Technische Reichsanstalt and gave up his full-time teaching duties. In 1893 he travelled to the United States for the International Electrical Congress in Chicago, touring American from August to October. On his return voyage he suffered a bad fall, and sustained a serious head injury. This was followed on New Year's Day of 1894 by the death of his most illustrious student and friend, H. Hertz. Thus before his own death that same year, Helmholtz had lived to see the passing on of two of his children, his first wife, and his best student.

Despite a career of lasting impact, Helmholtz's life was marked by the vagaries of human existence.

Patrick McDonald (EXTERN)