Recent research shows that research programmes (quantitative, qualitative and mixed) in education are not displaced (as suggested by Kuhn) but rather lead to integration. The objective of this study is to present a rationale for mixed methods (integrative) research programs based on contemporary philosophy of science (Lakatos, Giere, Cartwright, Holton, Laudan). This historical reconstruction of episodes from physical science (spanning a period of almost 300 years, 17th to 20th century) does not agree with the positivist image of science. Quantitative data (...) (empirical evidence) by itself, does not facilitate progress (despite widespread belief to the contrary), neither in the physical sciences nor in the social sciences (education) A historical reconstruction shows that both Piaget and Pascual-Leone’s research programs in cognitive psychology, follow the Galilean idealisation quite closely, similar to the research programs of Newton, Mendeleev, Einstein, Thomson, Rutherford, Millikan and Perl in the physical sciences. This relationship does not imply that researchers in education have to emulate research in the physical sciences. A major argument in favor of mixed methods (integrative) research programs is that it provides a rationale for hypotheses, theories, guiding assumptions and presuppositions to compete and provide alternatives. Similar to the physical sciences, this proliferation of hypotheses leads to controversies and rivalries, and thus facilitates the decision making process of the scientific community. It is concluded that mixed methods research programs (not paradigms) in education can facilitate the construction of robust strategies, provided we let the problem situation (as studied by practicing researchers) decide the methodology. (shrink)

Recent research shows that research programmes (quantitative, qualitative and mixed) in education are not displaced (as suggested by Kuhn) but rather lead to integration. The objective of this study is to present a rationale for mixed methods (integrative) research programs based on contemporary philosophy of science (Lakatos, Giere, Cartwright, Holton, Laudan). This historical reconstruction of episodes from physical science (spanning a period of almost 300 years, 17th to 20th century) does not agree with the positivist image of science. Quantitative data (...) (empirical evidence) by itself, does not facilitate progress (despite widespread belief to the contrary), neither in the physical sciences nor in the social sciences (education) A historical reconstruction shows that both Piaget and Pascual-Leone’s research programs in cognitive psychology, follow the Galilean idealisation quite closely, similar to the research programs of Newton, Mendeleev, Einstein, Thomson, Rutherford, Millikan and Perl in the physical sciences. This relationship does not imply that researchers in education have to emulate research in the physical sciences. A major argument in favor of mixed methods (integrative) research programs is that it provides a rationale for hypotheses, theories, guiding assumptions and presuppositions to compete and provide alternatives. Similar to the physical sciences, this proliferation of hypotheses leads to controversies and rivalries, and thus facilitates the decision making process of the scientific community. It is concluded that mixed methods research programs (not paradigms) in education can facilitate the construction of robust strategies, provided we let the problem situation (as studied by practicing researchers) decide the methodology. (shrink)

This paper examines the vital role played by electron microscopy toward the modern definition of viruses, as formulated in the late 1950s. Before the 1930s viruses could neither be visualized by available technologies nor grown in artificial media. As such they were usually identified by their ability to cause diseases in their hosts and defined in such negative terms as “ultramicroscopic” or invisible infectious agents that could not be cultivated outside living cells. The invention of the electron microscope, with magnification (...) and resolution powers several orders of magnitude better than that of optical instruments, opened up possibilities for biological applications. The hitherto invisible viruses lent themselves especially well to investigation with this new instrument. We first offer a historical consideration of the development of the instrument and, more significantly, advances in techniques for preparing and observing specimens that turned the electron microscope into a routine biological tool. We then describe the ways in which the electron microscopic images, or micrographs, functioned as forms of new knowledge about viruses and resulted in a paradigm shift in the very definition of these entities. Micrographs were not mere illustrations since they did the work for the electron microscopists. Drawing extensively on primary publications, we adduce the role of the new instrument in understanding the so-called eclipse phase in virus multiplication and the unexpected spinoffs of data from electron microscopy in naming and classifying viruses. Thus, we show that electron microscopy functioned not only to provide evidence, but also arguments in facilitating a reordering of the world that it brought into the visual realm. (shrink)

J. J. Thomson's discovery of the negatively charged corpuscle in 1897 is customarily regarded as the discovery of the electron. Thomson, however, did not immediately equate the charge of his corpuscle with the unitary charge, that is the ‘electron’, first proposed by Stoney in 1874. The aim of this paper is to clarify the means by which this identification was eventually made. To do this the work carried out by Thomson and his students at the Cavendish Laboratory between 1897 and (...) 1899 has been examined. From this reconstruction it emerges that, following his work on the mass-to-charge ratio of the corpuscle in 1897, Thomson and his school initiated and developed a series of techniques for measuring the charge of the ions. These techniques could not be used directly to measure the charge of the corpuscles because of the conditions required to produce them. Thomson therefore sought some other phenomenon that could be interpreted in terms of corpuscles and which allowed exploitation of the new charge-measuring techniques. He found such a phenomenon in the photoelectric effect, which allowed the measurement of both the charge and the mass-to-charge ratio of the corpuscle to be made. These measurements showed the charge of the corpuscle to be close to that assigned to the ‘electron’, and the two entities gradually became equated with each other. (shrink)

Recent research shows that research programmes (quantitative, qualitative and mixed) in education are not displaced (as suggested by Kuhn) but rather lead to integration. The objective of this study is to present a rationale for mixed methods (integrative) research programs based on contemporary philosophy of science (Lakatos, Giere, Cartwright, Holton, Laudan). This historical reconstruction of episodes from physical science (spanning a period of almost 300 years, 17 th to 20 th century) does not agree with the positivist image of science. (...) Quantitative data (empirical evidence) by itself, does not facilitate progress (despite widespread belief to the contrary), neither in the physical sciences nor in the social sciences (education) A historical reconstruction shows that both Piaget and Pascual-Leone's research programs in cognitive psychology, follow the Galilean idealisation quite closely, similar to the research programs of Newton, Mendeleev, Einstein, Thomson, Rutherford, Millikan and Perl in the physical sciences. This relationship does not imply that researchers in education have to emulate research in the physical sciences. A major argument in favor of mixed methods (integrative) research programs is that it provides a rationale for hypotheses, theories, guiding assumptions and presuppositions to compete and provide alternatives. Similar to the physical sciences, this proliferation of hypotheses leads to controversies and rivalries, and thus facilitates the decision making process of the scientific community. It is concluded that mixed methods research programs (not paradigms) in education can facilitate the construction of robust strategies, provided we let the problem situation (as studied by practicing researchers) decide the methodology. (shrink)

Historical accounts of the work of J. J. Thomson find a contradiction in his work. On the one hand, he is presented as a Maxwellian theoretical physicist dealing with a typically Victorian entity, the ether. On the other hand, the analysis of his experimental work at the Cavendish seems to have little connection with his mathematical work. In this paper, I discuss the metaphysical views of J. J. Thomson, and argue that his deep belief in the ultimate continuity of matter (...) can be seen to give a framework to both his theoretical and his experimental work. His metaphysical beliefs were not in the least shaken by the discovery of discrete phenomena and entities, not even by his suggestion of the existence of corpuscles later known as electrons. His formation in Cambridge, together with some ideas that he acquired in his youth at Owens College, Manchester, are the key to understanding his metaphysics and the role it plays in his scientific work. (shrink)

In 1927, George Paget Thomson, professor at the University of Aberdeen, obtained photographs that he interpreted as evidence for electron diffraction. These photographs were in total agreement with de Broglie's principle of wave–particle duality, a basic tenet of the new quantum wave mechanics. His experiments were an initially unforeseen spin-off from a project he had started in Cambridge with his father, Joseph John Thomson, on the study of positive rays. This paper addresses the scientific relationship between the Thomsons, father and (...) son, as well as the influence that the institutional milieu of Cambridge had on the early work of the latter. Both Thomsons were trained in the pedagogical tradition of classical physics in the Cambridge Mathematical Tripos, and this certainly influenced their understanding of quantum physics and early quantum mechanics. In this paper, I analyse the responses of both father and son to the photographs of electron diffraction: a confirmation of the existence of the ether in the former, and a partial embrace of some ideas of the new quantum mechanics in the latter. (shrink)

In the second half of the nineteenth century, gas discharge research was transformed from a playful and fragmented field into a new branch of physical science and technology. From the 1850s onwards, several technical innovations – powerful high-voltage supplies, the enhancement of glass-blowing skills, or the introduction of mercury air-pumps – allowed for a major extension of experimental practices and expansion of the phenomenological field. Gas discharge tubes served as containers in which resources from various disciplinary contexts could be brought (...) together; along with the experimental apparatus built around them the tubes developed into increasingly complex interfaces mediating between the human senses and the micro-world. The focus of the following paper will be on the physicist and chemist Johann Wilhelm Hittorf , his educational background and his attempts to understand gaseous conduction as a process of interaction between electrical energy and matter. Hittorf started a long-term project in gas discharge research in the early 1860s. In his research he tried to combine a morphological exploration of gas discharge phenomena – aiming at the experimental production of a coherent phenomenological manifold – with the definition and precise measurements of physical properties. (shrink)

This paper attends to two main tasks. First, I introduce the notion of perspectival disagreement in science. Second, I relate perspectival disagreement in science to the broader issue of realism about science: how to maintain realist ontological commitments in the face of perspectival disagreement among scientists? I argue that often enough perspectival disagreement is not at the level of the scientific knowledge claims but rather of the methodological and justificatory principles. I introduce and clarify the notion of ‘agreeing-whilst-perspectivally-disagreeing’ with an (...) episode from the history of modern physics: namely, how we came to agree about the electric charge as a minimal natural unit despite different scientific perspectives and associated data-to-phenomena inferences available for it in the period 1897–1906. (shrink)

The history of the Cavendish Laboratory is a fascinating subject to study, not just because this famous centre of experimental physics produced a large number of Nobel Laureates but also because it gives us an insight into the unique milieu of the Cambridge physics community. The evolution of the Cavendish Laboratory, however, was not as smooth as might be expected, and the prestige and reputation of its first directors – James Clerk Maxwell, Lord Rayleigh, Joseph John Thomson and Ernest Rutherford (...) – did not automatically guarantee a rosy future. Like other British physics laboratories in the late nineteenth century, the Cavendish Laboratory was a new species to meet the pressure and demand from society. Since it propagated new values and modes of doing science, a struggle with old traditions could not be avoided, and the early history of the Cavendish Laboratory illustrates how the ‘old’ and ‘new’ values fought and negotiated each other in late Victorian Cambridge. (shrink)

This article examines the origins and development of J. J. Thomson's chemical thought, and the reception of his theories by chemists. Thomson's interest in chemical combination and atomic theories of matter dates from his formative schooldays at Owens College, Manchester. These themes constituted a persistent leitmotif in the development of Thomson's style of thought, and provided a powerful stimulus which enabled him to enunciate the concept of electrons as fundamental particles. Thomson's influence on chemists during the years 1903 to 1923 (...) reflects the richness and fertility of his chemical thought. He influenced the absorption of the Victorian physical tradition by American chemists, thus adding a mechanistic, picture-embedded style to theoretical chemistry. Thomson's style of thought resonated with the needs of American chemists, but was ignored in Germany. (shrink)

In this paper we analyse the approach to interpreting atomic spectra in the framework of classical physics from the discovery of the electron in 1897 to Bohr's atomic model of 1913. Taken as a whole, efforts in this direction are part of a remarkable intellectual endeavour in which the classical theoretical framework seems to have been exploited to its full potential. By demonstrating the limits and weaknesses of classical physics in solving the problem of spectral emissions, these attempts opened the (...) way to a complete break from traditional thought and the introduction of the new quantum ideas. (shrink)