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From Galvanism to Electrodynamics: the Transformation of German Physics and Its Social Context

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From Galvanism to Electrodynamics: the Transformation of German Physics and Its Social Context From Galvanism to Electrodynamics: The Transformation of German Physics and Its Social Context By Kenneth L. Caneva* "On what sorts of occasions, and by what processes and procedures, are the or fundamental concepts constellations of presuppositions characteristic of the modes of thought current in one human generation discredited and abandoned or in favour of other successor-concepts presuppositions?"1 1. Introduction 2. The Science of the Concrete The Qualitative Nature of Experiment The Role ofExperiment: The InductivistIdeal and theRejection of the Hypothetico-Deductive Method Mathematical versus Physical Theories Explanation as Schematization 3. The Science of the Abstract Mathematics and Abstraction Experiment and Measurement The Hypothetico-Deductive Method 4. External Factors in the Transition from Concretizing to Abstract ing Science The Institutionaland SocialContext of Scientific Change Toward the Professionalization of Science Toward the Redefinition of the Individual in Society The SocialDimension of Scientific Knowledge The Legitimation of Scientific Activity: A Functional Analysis Social and Scientific Styles of Thought: A Structural Comparison "Centrum Algemene Vorming, Vrije Universiteit, De Boelelaan 1083, Postbus 7161, Amsterdam-Buitenveldert, The Netherlands. This paper is based on a dissertation I written under Thomas S. Kuhn, for whose original guidance and encouragement remain grateful. In its present form it has profited from the criticisms of Louis Boon, Lewis Pvenson. Martin Rudwick. Tane Suearman, and Steven Turner. 1Stephen Toulmin, Human Understanding (Princeton, 1972), 1, 75, paraphrasing Robin George Colling wood, An Essay on Metaphysics (Oxford, 1940), p. 73. 63 64 KENNETH L. CANEVA 1. INTRODUCTION aware a Historians have long been that German science underwent the first profound qualitative and quantitative transformation during half of the nineteenth century. This paper investigates the qualitative a aspects of that change in single field of study, electricity and mag netism. Because this area of physical research was more actively pur a sued, and pursued by greater number of individuals, than any other, itmay reasonably serve as a first approximation to the state of affairs in other areas of physics as well. Only future research will indicate whether certain generalizations based on this study depend upon factors peculiar to research in electricity and magnetism. A broad overview of the developments in electricity and magnetism in Germany during this period reveals the following picture. The early years of the century saw a flurry of activity on the voltaic pile and various associated electrostatic and electrochemical phenomena by men such as Ritter, Erman, J?ger, Pfaff, and, in the 1810's, Schweigger. (See Table 1 for dates and given names.) With the dis came covery of electromagnetism in 1820 contributions by Seebeck, Muncke, Poggendorff, Pohl, and Schmidt, in addition to continued work by Erman, Pfaff, and Schweigger. These individuals set the tone for the study of electricity in Germany during the first quarter of the nineteenth century. Although some of them remained active in the field into the 1830's (Erman and Muncke), 1840's (Pfaff and Pohl), and a new even later (Poggendorff), approach to the study of physics had already begun to emerge in the late 1820's, represented firstby Ohm's and Fechner's treatment of current and the pile. In the next decade this new approach was extended to electromagnetism by Lenz, Jacobi, Gauss, and Weber and to terrestrial magnetism and static electricity by Moser and Riess. In the mid-1840's it appeared in the theoretical electrodynamics of Fechner, Weber, Neumann, and Grassmann. These twenty individuals were, with Dove, the most important contributors to electricity and magnetism in Germany dur ing the period 1800 to 1846, their importancebeing judged on the basis of contemporary and subsequent recognition and extent of pub lication in the leading scientific journals. The sample represented in Table 1 has been checked for completeness against two extensive a specialized bibliographies and standard history, even though it is a impossible to select historiographically useful sample solely on the an basis of objective procedure such as entry-counting.2 a 2For discussion of other possible candidates for inclusion, see Kenneth L. Caneva, and Generational in Conceptual Change German Physics: The Case of Electricity, 1800-1846 (diss., Princeton Univ., 1974), pp. 19-22, for the results of a numerical tabulation based to and the First Table. 1. Principle German Contributors Electricity Magnetism during Half of the Nineteenth Century - 1760 - ERMAN, Paul (1764-1851) - SCHMIDT, Georg Gottlieb (1768-1837) - 1770 SEEBECK, Thomas Johann(1770-1831) - MUNCKE, Georg Wilhelm (1772-1847) - RITTER, JohannWilhelm (1776-1810) - GAUSS, Carl Friedrich (1777-1855) - SCHWEIGGER, JohannSalomo Christoph (1779-1857) - 1780 - POHL, Georg Friedrich (1788-1849) - OHM, Georg Simon (1789-1854) - 1790 - POGGENDORFF, JohannChristian (1796-1877) - NEUMANN, Franz Ernst (1798-1895) 1800 - DOVE, Heinrich Wilhelm (1803-1879) ( LENZ, Heinrich FriedrichEmil (1804-1865) RIESS, Peter (1804-1883) - .j Theophil MOSER, Ludwig Ferdinand (1805-1880) (WEBER, Wilhelm Eduard (1804-1891) - GRASSMANN, Hermann G?nther (1809-1877) - 1810 66 KENNETH L. CANEVA It is the major thesis of this paper that these scientists represented a two very different paradigms of science, distinction implicit in the areas above sketch of major figures and of research.3 The earlier ap was proach, called "concretizing science" in Section 2, characterized the belief in particular by the qualitative nature of its experiments, by a source that experience is direct and epistemologically primary of an scientific knowledge, and by the notion that there is essential distinction between physical understanding and mathematical de scription. The later approach, the "abstracting science" of Section 3, was, in contrast, marked by an overriding concern with quantitative use measurement, by the free of theoretical assumptions in conjunc tion with their subsequent hypothetico-deductive control, and by the as relative abstractness of what it regarded scientific knowledge. The explication of these two paradigms and the presentation of evidence that they were in fact held by the members of the two groups will be the task of the next two sections of this paper. To some extent these groups have been identified not only in terms a on of their attachment to particular paradigm, but also the basis of their intercommunication and attention to the same problems.4 Schmidt, for example, whose appreciation formathematics and use of the hypothetico-deductive method were atypical of his generation, has nevertheless been classed among the concretizing scientists, al an a beit as something of exception, because he was clearly member of the same larger community and addressed himself to it and to its problems; for example, to the anti-Amp?rian theory of transversal magnetism. His work was unknown to the younger scientists. Pohl, well known in his day as virtually the only exponent of Natur philosophie among German university physicists, was regarded se on the following three works: Heinrich Wilhelm Dove, "Literatur des Magnetismus und der Elektricit?t,"Repertorium der Physik, 5 (1844), 152-288;Catalogue of theWheeler Gift of Books, Pamphlets and Periodicals in the Library of theAmerican Institute of Electrical Engineers, D. ed. William Weaver, 2 vols. (New York, 1909); and Edmund Hoppe, Geschichte der Elektricit?t(Leipzig, 1884; rpt.Wiesbaden, 1969).My terminifor this tabulation were 1800 and a 1846: 1800 is meaningful beginning because Volta's announcement of his pile in a era that year began new in electricity; 1846 is convenient because it includes the impor men tant electrodynamics work of 1845-1846 but excludes almost all the early papers of as such Kirchhoff and Beetz, who belonged to the next generation of German physicists born aroiind 1820. use 3I the word "paradigm" to mean "the entire constellation of beliefs, values, and so on a techniques, shared by themembers of given community" (Thomas S. Kuhn, The Structure of Scientific Revolutions, 2nd ed. [Chicago & London, 1970], p. 175). was 4On this basis it proved impossible to place Dove, most of whose work in but who on meterology also did experimental work electromagnetic induction, particu with to larly respect qualitative differences between frictional and galvanic electricity. In to addition the idiosyncratic quality of his work, he seems not to have interacted with as an was anyone except Riess, who, amateur studying static electricity, himself some an thing of anomaly. See also note 213. FROMGALVANISM TO ELECTRODYNAMICS 67 riously enough by his contemporaries to warrant consideration, and his papers continued to be published in Poggendorffs Annalen der Physik, the supposed enemy of Naturphilosophie.5 Pohl addressed same himself to the problems that occupied the other representatives of concretizing science, although his treatment was different in some respects. Poggendorff, the oldest member of the younger generation, was more at with intellectually home the science of the preceding than with the generation style of physics being developed by his contemporaries. As might be suspected, his pivotal position as editor a of the Annalen der Physik has contributed to distorted image of physics in Germany during the second quarter of the nineteenth cen was tury. Poggendorff not among those who assimilated
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