This study was completed at Dartmouth College, Hanover, NH, USA. I would like to thank Naomi Oreskes, Joseph Harris, Richard Kremer and Leonard Rieser for their most valuable discussions. I also received helpful comments on an earlier draft of this paper from Jan Faye, Henry Folse and Mara Beller. Some preliminary translations of German text were completed by Matthew Henken. Finally, I would like to thank the Rockefeller Center at Dartmouth College for providing financial support during the course of this research.

Permission to quote from the Einstein Archives material was granted by the Albert Einstein Archives, The Hebrew University of Jerusalem, Israel.

¹ Einstein, A ., ‘Autobiographical notes’, in Albert Einstein: Philosopher-Scientist (ed. Schilpp, P. A.), Evanston, III., 1949, 94.Google Scholar

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³ Nersessian, N., ‘The cognitive sciences and the history of science’, in Conference on Critical Problems and Research Frontiers in History of Science and History of Technology, Madison, Wisconsin: History of Science Society, 1991, 96Google Scholar. Daston, Lorraine and Otte, Michael seem to encourage this, writing that ‘Individual style may be consigned to the psychoanalytical blackbox of quirk and creativity’Google Scholar (Daston, L. and Otte, M., ‘Introduction: style in science’, Science In Context (1991), 4, 230CrossRefGoogle Scholar). This black-boxing applies to both the ‘micro-sociological’ studies of the social interactions within a single laboratory or community, e.g. Pickering, A., Constructing Quarks, Edinburgh, 1984Google Scholar; Latour, B. and Woolgar, S., Laboratory Life, 2nd edn, Princeton, 1986Google Scholar; Latour, B., Science in Action, Cambridge, Mass., 1987Google Scholar; and Traweek, S., Beamtimes and Lifetimes, Cambridge, Mass., 1988Google Scholar, and the ‘macro-sociological’ investigations of cultural influences and the problems of social order, e.g. Forman, P., ‘Weimar culture, causality, and quantum theory, 1918–1927: adaptation by German physicists and mathematicians to a hostile environment’, Historical Studies in the Physical Sciences (1971), 3, 1–115CrossRefGoogle Scholar; and Shapin, S. and Schaffer, S., Leviathan and the Air-Pump, Princeton, 1985Google Scholar. Cf. Radder, H., ‘Normative reflexions on constructivist approaches to science and technology’, Social Studies of Science (1992), 22, 141–73CrossRefGoogle Scholar for a recent critique of various socio-historical approaches.

⁴ Moore, R., Niels Bohr: The Man, His Science, and the World They Changed, Cambridge, Mass., 1966, 177Google Scholar. Cf. Hoffman, B., Albert Einstein: Creator and Rebel, New York, 1972Google Scholar; and Bernstein, J., Einstein, New York, 1973.Google Scholar

⁵ See Rudwick, M., The Great Devonian Controversy, Chicago, 1985, 418–28.CrossRefGoogle Scholar

⁶ Rudwick, , op. cit. (5), 409.Google Scholar

⁷ Keller, E. F., A Feeling for the Organism, New York, 1983, 49–50Google Scholar. Cf., e.g., Klein, M., Paul Ehrenfest, New York, 1970, iGoogle Scholar; Hankins, T. L., ‘In defense of biography: the use of biography in the history of science’, History of Science (1979), 17, 1–16CrossRefGoogle Scholar; Heilbron, J., The Dilemmas of an Upright Man: Max Planck as Spokesman for German Science, Berkeley, 1986Google Scholar; and Smith, C. and Wise, M. N., Energy and Empire: A Biographical Study of Lord Kelvin, Cambridge, 1989Google Scholar. This biographical use of ‘personality’ eschews the psychologist's explanation in terms of ‘traumas’ and ‘neuroses’, which, as Lorraine Daston explains, evokes a ‘common horror’ from historians, sociologists, and philosophers of science alike. (Daston, L., ‘The moral economy of science’, in Critical Problems and Research Frontiers, op. cit. (3), 424.)Google Scholar

⁸ On Einstein, see, e.g., Frank, P., Einstein: His Life and Times, New York, 1947Google Scholar; Hoffman, , op. cit. (4)Google Scholar; Bernstein, , op. cit. (4)Google Scholar; and Pais, A., ‘Subtle is the Lord…’: The Science and the Life of Albert Einstein, New York, 1982Google Scholar. On Bohr, see, e.g., Moore, , op. cit. (4)Google Scholar; Rozental, S. (ed.), Niels Bohr: His Life and Work as Seen by bis Friends and Colleagues, New York, 1967Google Scholar; and Pais, A., Niels Bohr's Times in Physics, Philosophy, and Polity, Oxford, 1991Google Scholar. Of all these biographies, Pais' pair offers the most valuable insight into both Einstein's and Bohr's personalities and styles of work. Yet his books are limited by Pais' own indifference to history and philosophy of science: he dismisses efforts to trace philosophical roots of Bohr's complementarity as ‘without basis in fact’, and declares himself ‘unable to appreciate what all the fuss is about’, regarding the Einstein–Podolsky–Rosen paper (Pais, , Niels Bohr's Times, 1991, 24, 430Google Scholar). For more on the need for symmetry in historical accounts of controversy, cf. Bloor, D., Knowledge and Social imagery, 2nd edn, Chicago, 1991, 175–9Google Scholar; Shapin, and Schaffer, , op. cit. (3), 11–12Google Scholar; and Rudwick, , op. cit. (5), 12.Google Scholar

⁹ Both Henry Folse's and Dugald Murdoch's book-length investigations of Bohr's philosophy of physics dedicate merely fleeting glances to Einstein's position: Folse, H., The Philosophy of Niels Bohr: The Framework of Complementarity, New York, 1985Google Scholar; and Murdoch, D., Niels Bohr's Philosophy of Physics, New York, 1987CrossRefGoogle Scholar. Symmetric accounts address both sides equally, but further dissolve the people behind the arguments: Einstein and Bohr the physicists, with particular motivations, goals and ‘expectations’, are nowhere to be found. Cf., e.g., Hooker, C. A., ‘The nature of quantum mechanical reality: Einstein versus Bohr’, in Paradigms & Paradoxes: The Philosophical Challenge of the Quantum Domain (ed. Colodny, R.), Pittsburgh, 1972, 67–302Google Scholar; and Bunge, M., ‘The Einstein–Bohr debate: who was right about what?’, in Einstein Symposium Berlin (ed. Nelkowski, H.), New York, 1979, 204–19CrossRefGoogle Scholar. All of these philosophical accounts of the debate share a common disregard for how Einstein's and Bohr's respective positions reflected the physicists' own particular approaches to science.

Henry Folse has recently called for a redrawing of philosophers' maps of the Einstein–Bohr debate, in order better to reflect the issues the way they were actually discussed by the participants (Folse, H., ‘Niels Bohr's concept of reality’, in Symposium on the Foundations of Modern Physics (ed. Lahti, P. and Mittelstaedt, P.), Singapore, 1987, 161–79Google Scholar; Folse, H., ‘The Bohr–Einstein debate and the philosophers' debate over realism versus anti-realism’, paper presented at the 06 1992 Beijing Conference on Realism)Google Scholar. This approach on the philosophers' side fits nicely with the personal-context approach to history of science addressed here. My thanks to Professor Folse for providing copies of these papers.

¹⁰ See Heisenberg's ‘Introduction’ in Born, M., The Born–Einstein Letters (tr. Born, I.), New York, 1971, xGoogle Scholar; and Fine, A., The Shaky Game: Einstein, Realism, and the Quantum Theory, Chicago, 1986, chs. 2 and 3.Google Scholar

¹¹ Fine, , op. cit. (10), 19.Google Scholar

¹² Fine, , op. cit. (10), 34–5.Google Scholar

¹³ Throughout this paper, I use the word ‘language’ in the narrow sense of words and descriptions as they are written or spoken, rather than as a general term for communication of any kind. Einstein and Bohr used the word ‘language’ in this sense in their own writings. Thus, ‘language’ here is different from, for example, visual pictures or mathematical formalism. See Rudwick, M., ‘The emergence of a visual language for geological science, 1760–1840’, History of Science (1976), 14, 149–95CrossRefGoogle Scholar, for a discussion of non-verbal, visual languages in science.

¹⁴ Bohr, N., Atomic Theory and the Description of Nature, New York, 1934, 5.Google Scholar

¹⁵ Bohr, N., Atomic Physics and Human Knowledge, New York, 1958, 67.Google Scholar

¹⁶ See Crease, R. and Mann, C., The Second Creation: Makers of a Revolution in Twentieth-Century Physics, New York, 1986, 20–1Google Scholar; and Pais, A., Niels Bohr's Times in Physics, Philosophy, and Polity, Oxford, 1991, 102–3Google Scholar. Many Bohr scholars have split over the primacy of language in Bohr's personal approach to science, as presented here. Whereas Jan Faye, Henry Folse and Mara Beller have expressed reservations (in personal communications) about the degree to which Bohr's personal approach to physics relied upon semantic-linguistic considerations, Edward MacKinnon, Catherine Chevalley and John Honner have portrayed Bohr's work, in Honner's words, in terms of ‘the relationship…between word and world, and between language and fact’ (Honner, J., The Description of Nature: Niels Bohr and the Philosophy of Quantum Physics, New York, 1987, 7Google Scholar. See also MacKinnon, E., ‘Bohr and the realism debate’, in Niels Bohr and Contemporary Philosophy (ed. Faye, J. and Folse, H.), Dordrecht, 1994, 279–302CrossRefGoogle Scholar; and Chevalley, C., ‘Niels Bohr's words and the Atlantis of Kantianism’Google Scholar, in ibid., 33–56). It is clear that Bohr was interested in communication from the start of his career, and in my interpretation, his emotional preference for working with groups came in tandem with a deep-seated interest in the role of language in science. He made public pronouncements about the role of language more frequently following the 1935 paper by Einstein, Podolsky and Rosen (discussed below), but the methodological roots of his semantic orientation may be traced earlier than his post-1935 work.

¹⁷ Letter from Einstein to Jacques Hadamard, printed in Appendix II of Hadamard, J., The Psychology of Invention in the Mathematical Field, Princeton, 1945, 142–3Google Scholar. Also quoted in Holton, G., Thematic Origins of Scientific Thought, 2nd edn, Cambridge, Mass., 1988, 386.Google Scholar

¹⁸ Einstein, to Hadamard, , in Hadamard, , op. cit. (17), 142–3Google Scholar. Also quoted in Miller, A., Imagery in Scientific Thought: Creating 20th-century Physics, Boston, 1984, 221.CrossRefGoogle Scholar

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²¹ The correspondence between Rutherford and Bohr regarding these papers is reprinted in Niels Bohr Collected Works: Volume 2: Work on Atomic Physics (1912–17) (ed. Hoyer, V.), Amsterdam, 1981, 577–89Google Scholar. See Moore, , op. cit. (4), 60–3.Google Scholar

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²³ See Pais, , op. cit. (16), 168–72Google Scholar, and Moore, , op. cit. (4), 96–9.Google Scholar

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²⁵ Pais, , ‘Subtle Is the Lord…’, op. cit. (8), 35, 355Google Scholar; Pais, , op. cit. (16), 227.Google Scholar

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³¹ This approximate value comes from a survey of the resources compiled in the Niels Bohr Collected Works volumes.

³² Bohr, N., Kramers, H. and Slater, J., ‘The quantum theory of radiation’, reprinted in Sources of Quantum Mechanics (ed. van der Waerden, B. L.), New York, 1967, 162.Google Scholar

³³ See Bohr, N., ‘Can quantum-mechanical description of physical reality be considered complete?’, Physical Review (1935), 48, 696–702.CrossRefGoogle Scholar

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³⁵ Werner Heisenberg, interview conducted by Kuhn, Thomas S., 30 11 1962, p. 14Google Scholar of transcript; copies in the American Institute of Physics Niels Bohr Library, New York, and other repositories of the Archives for the History of Quantum Physics (AHQP-AIP). Cf. Folse, , op. cit. (22), 41–2.Google Scholar

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³⁸ Quoted in Petersen, A., ‘The philosophy of Niels Bohr’, in Niels Bohr: A Centenary Volume (ed. French, A. P. and Kennedy, P. J.), Cambridge, Mass., 1985, 302Google Scholar. Henry Folse rightfully cautions against placing too much emphasis upon Petersen's very linguistic portrayal of Bohr's philosophy: many of the quotations attributed to Bohr were not written down, but rather recalled by Petersen during a time when linguistic analysis was very popular (personal communication).

³⁹ Bohr, N., unpublished ‘Post scriptum,’ dated 13 08 1957Google Scholar. Niels Bohr Archive: Bohr Manuscripts, reel 22; copies in AHQP-AIP. This short article was intended to follow the reprint of his ‘Discussion with Einstein on epistemological problems in atomic physics’ in Bohr, , op. cit. (15).Google Scholar

⁴⁰ Quoted in Petersen, , op. cit. (38), 305.Google Scholar

⁴¹ Jaki, S., God and the Cosmologists, Washington, DC, 1989, 138–9Google Scholar. Cf. Fine, , op. cit. (10), 34, 124Google Scholar, where he dismisses Bohr as simply ‘the nonrealist’, and calls Bohr's response to the 1935 Einstein–Podolsky–Rosen paper ‘textbook neopositivism’. Jan Faye's recent analysis also paints Bohr as an anti-realist. See Faye, J., Niels Bohr: His Heritage and Legacy, Boston, 1991.CrossRefGoogle Scholar

⁴² Several analyses of Bohr's philosophy of physics have attempted to demonstrate a possible compatibility between Bohr's ontological position and realism: cf. Folse, , op. cit. (22), 222–60Google Scholar; Murdoch, , op. cit. (9), 200–22Google Scholar; and Daniel, W., ‘Bohr, Einstein and realism’, Dialectica (1989), 43, 250–3CrossRefGoogle Scholar. Yet this approach can lead to pitfalls. For example, Murdoch states that Bohr was partly a ‘weak realist’ (p. 216), an ‘instrumental realist’ (p. 222), and that he incorporated a ‘pragmatist strain’ (p. 231). This constant need to qualify each description illustrates the benefits of adopting Arthur Fine's stance of dropping ‘isms’ from the analysis (Fine, , op. cit. (10), 9Google Scholar). This sentiment is evident in some of Henry Poise's recent work, in which he has explained that Einstein's and Bohr's confrontation will be ‘misconstrued’ if staged ‘on the philosopher's battle plain of realism versus antirealism’. Folse, H., ‘The Bohr-Einstein debate and the philosophers' debate over realism versus anti-realism’, paper presented at the 06 1992Google Scholar Beijing Conference on Realism. For a brief look at questions of Bohr's ontological approach and modern particle physics, see Kaiser, D., ‘Niels Bohr's conceptual legacy in contemporary particle physics’ in Niels Bohr and Contemporary Philosophy (ed. Paye, J. and Folse, H.), Dordrecht, 1994, 257–68.CrossRefGoogle Scholar

⁴³ Cf., e.g., the essays in Bohr, , op. cit. (14)Google Scholar; and Murdoch, , op. cit. (9), 208.Google Scholar

⁴⁴ Kant, I., Critique of Pure Reason (tr. Smith, N. K.), New York, 1929, 24 (Bxix–xx)Google Scholar. See Kaiser, D., ‘More roots of complementarity: Kantian aspects and influences’, Studies in History and Philosophy of Science (1992), 23, 213–39CrossRefGoogle Scholar. The Bohr–Kant question is also examined briefly in Honner, , op. cit. (16).Google Scholar

⁴⁵ This outline is for the sixth lecture of Bohr's Gifford Lectures. The notes are dated 14 July 1949. Niels Bohr Archive: Bohr Manuscripts, reel 19; copies in AHQP-AIP.

⁴⁶ Rosenthal-Schneider, I., Reality and Scientific Truth: Discussions with Einstein, von Laue, and Planck, Detroit, 1980, 92Google Scholar. This and the following discussion of Einstein's ontological position, scientific goal and methodological approach to science all concern his outlook as it had developed and stabilized prior to the beginning of the debate, i.e. roughly by 1920. For descriptions of Einstein's earlier positions, cf. Fine, , op. cit. (10), 12–25Google Scholar; Holton, , op. cit. (17), 191–370Google Scholar; and Holton, G., The Advancement of Science, and its Burdens, New York, 1986, 57–76.Google Scholar

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⁵⁰ Arthur Miller notes that visual thinking and realism were ‘allied’ in classical physics, and that Einstein's own particular ‘predilection for visual thinking’ reflected in many ways elements of Boltzmann's and Helmholtz's non-verbal styles. Miller, , op. cit. (18), 48, 112 and 128Google Scholar. ‘Intuition’ here should be understood as ‘mental visualization’, rather than denoting mystical ‘clairvoyant’ qualities of Einstein's ‘genius’, as Banesh Hoffman repeatedly uses it throughout Hoffman, , op. cit. (4).Google Scholar

⁵¹ Einstein, A. and Infeld, Leopold, The Evolution of PhysicsGoogle Scholar, as quoted in Gregory, B., Inventing Reality: Physics as Language, New York, 1988, 185.Google Scholar

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⁵⁵ Fine, , op. cit. (10), 137.Google Scholar

⁵⁶ Fine, , op. cit. (10), 105.Google Scholar

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⁶⁴ Letter from Einstein, to Solovine, , 1 01 1951Google Scholar, reprinted and translated in Solovine, , op. cit. (58), 118–21.Google Scholar

⁶⁵ Einstein, , op. cit. (49), 226Google Scholar. Both Gerald Holton and Arthur Fine have noted that the title of this essay has been poorly translated: the original ‘Motiv des Forschens’ stands closer to ‘Motives for research’ than to the official translation as ‘Principles of research’. Einstein's use of the word ‘motives’ enhances the notion that he perceived science as a very personal endeavour. See Fine, , op. cit. (10), 109.Google Scholar

I do not mean to imply any sort of social or group agreement or solidarity by the term ‘unified’. Rather, ‘unified’ for Einstein meant that the various principles are themselves mutually woven together into a single coherent Weltbild. This unification was a very private endeavour. My thanks to Rich Kremer for pointing out this possible misinterpretation.

⁶⁶ Einstein, , op. cit. (49), 227Google Scholar. Cf. Holton, G.'s chapter ‘Einstein's model for constructing a scientific theory’Google Scholar, in Holton, , op. cit. (46), 28–56.Google Scholar

⁶⁷ See, e.g., Pais, , op. cit. (25), ch. 17.Google Scholar

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⁷⁶ Einstein, , ‘Physics and reality’Google Scholar, in Seelig, , op. cit. (19), 294Google Scholar. Don Howard's investigation of Einstein's disapproval of quantum mechanics highlights two specific examples of Einstein's general methodological approach. Howard's treatment, like Fine's, emphasizes Einstein's reluctance to give up the general principles of ‘locality’ and ‘separability’. (Cf. Howard, D., ‘Einstein on locality and separability’, Studies in History and Philosophy of Science (1985), 16, 171–201CrossRefGoogle Scholar.) For Einstein, ‘locality’ and ‘separability’ were two (axiomatic) general principles which should not be sacrificed in the name of complementarity.

⁷⁷ Letter from Einstein, to Hubert, David, 24 05 1918Google Scholar. Einstein Archives, Box 15, #13–125. ‘Es imponiert mir, dass man diese Dinge von so allgemeinem Standpunkt übersehen kann.’.

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⁷⁹ Letter from Einstein, to Schrödinger, , 31 05 1928Google Scholar. Reprinted and translated in Przibram, K. (ed.), Letters on Wave Mechanics (tr. Klein, M.), New York, 1967, 31Google Scholar. Emphasis added. Also quoted in Fine, , op. cit. (10), 18.Google Scholar

⁸⁰ Bohr, , op. cit. (14), 8Google Scholar. Emphasis added. Cf. Murdoch, , op. cit. (9), 37–9Google Scholar; and Folse, , op. cit. (22), 100–1, 128–9.Google Scholar

⁸¹ See Serway, R., Moses, C. and Moyer, C., Modem Physics, New York, 1989, 94Google Scholar. In this text, the limit expression is given for n → ∞, instead of h → 0 as I have written. The choice of variables here evinces the difference between the two types of specific limiting conditions, i.e. allowing h (Planck's constant) to tend to zero involves the assignment of certain values to theoretical constants, whereas n (principal quantum number) → ∞ is an example of the restriction to certain limiting domains of application. Either way, the use of the mathematical limit notation seems to me to be the best way of expressing the asymptotic agreement requirement of Bohr's correspondence principle.

⁸² Bohr, N., ‘On the quantum theory of line-spectra’, in Sources of Quantum Mechanics (ed. van der Waerden, B. L.), New York, 1967, 116.Google Scholar

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⁸⁵ Bohr, , op. cit. (70), 228. Emphasis added.Google Scholar

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⁸⁷ This term is inspired by David Bohm's protests against Einstein's physical plausibility criterion: ‘I have the feeling that you do not wish to accept this point of view [regarding the measurement of an electron's momentum] on the grounds that you regard it as implausible…It is not desirable to require that [a theory] fit your own personal standards of plausibility, which after all, depend very much on our own particular and limited experience.’ Letter from David Bohm to Einstein, undated (‘probably 1950/51’). Einstein Archives, Box 8, #8–001. Emphasis added.

⁸⁸ Fine, , op. cit. (10), 22.Google Scholar

⁸⁹ Letter from Einstein, to Hoe, Henry Allen, 28 11 1954Google Scholar, Einstein Archives, Box 6, #6–056. Notes between Paul Ehrenfest and Einstein (undated, probably from the fifth Solvay conference, 1927) similarly reveal Einstein's constant awareness of ‘future development’. Ehrenfest wrote to Einstein ‘Don't laugh!’ (‘Lache nicht!’), to which Einstein replied, ‘I laugh only at the naiveté [presumably of the proponents of quantum mechanics, the subject of the conference]. Who knows who will be laughing in the coming years.’ (‘Ich lache nur über die Naivotät. Wer weiss wer in einigen Jahren lacht.’) Einstein Archives, Box 11, #10–153.

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⁹¹ See, e.g., Heisenberg, W., The Physical Principles of the Quantum Theory, New York, 1930, 65.Google Scholar

⁹² Einstein, A., Podolsky, B. and Rosen, N., ‘Can quantum-mechanical description of physical reality be considered complete?’, Physical Review (1935), 47, 777–80CrossRefGoogle Scholar. Hereafter I will refer to this paper simply as ‘EPR’.

⁹³ EPR., op. cit. (92), 777–80Google Scholar. Cf., e.g., Hooker, , op. cit. (9)Google Scholar; Rosen, N., ‘Can quantum-mechanical description of physical reality be considered complete?’, in Albert Einstein: His Influence on Physics, Philosophy and Politics (ed. Aichelburg, P. C. and Sexl, R. U.), Braunschweig, 1979, 57–68CrossRefGoogle Scholar; Fine, , op. cit. (10)Google Scholar; Redhead, M., Incompleteness, Nonlocality, and Realism, New York, 1987, ch. 3Google Scholar; Deltete, R. and Guy, R., ‘Einstein's opposition to the quantum theory’, American Journal of Physics (1990), 58, 673–83CrossRefGoogle Scholar; and Kaiser, , op. cit. (44).Google Scholar

⁹⁴ Letter from Einstein, to Schrödinger, , 19 06 1935Google Scholar. Einstein Archives, Box 28, #22–047. Portions of this letter are translated and reprinted in Fine, , op. cit. (10), 35–6Google Scholar, from which the above text is quoted. Yet where Fine supplies ‘paper’, Einstein's actual referent is ‘little treatise’ [‘kleine Abhandlung’]. The adjective ‘little’ here might simply refer to the brevity of the EPR paper (four pages); but it could also mean ‘petty’, thereby adding weight to Einstein's derision of the EPR paper's ‘smothering formalism’.

⁹⁵ Deltete, and Guy, , op. cit. (93), 679.Google Scholar

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¹⁰¹ Bohr repeatedly remarked upon this aspect of quantum mechanics, describing, e.g., ‘the extent to which renunciation of the visualization of atomic phenomena is imposed on us’, and ‘emphasiz[ing] how far, in quantum theory, we are beyond the reach of pictorial visualization’ (Bohr, , op. cit. (70), 222, 232Google Scholar). See Miller, , op. cit. (18)Google Scholar, especially for the differences between Anschauung and Anschaulichkeit in quantum theory: ‘in the atomic domain visualization and visualizability are mutually exclusive… [whereas] in classical physics visualization and visualizability are synonymous’. Miller, , op. cit. (18), 154.Google Scholar

¹⁰² Letter from Einstein, to Bonofield, Paul, 18 09 1939Google Scholar. Einstein Archive, Box 6, #6–118–1.

¹⁰³ Letter from Einstein, to Eddington, Arthur S., 22 01 1926Google Scholar. Emphasis added. Einstein Archive, Box 10, #9–288.

¹⁰⁴ Bohr, , op. cit. (33).Google Scholar

¹⁰⁵ Bohr, , op. cit. (33), 699.Google Scholar

¹⁰⁶ Bohr, , op. cit. (33), 699.Google Scholar

¹⁰⁷ Cf. Hooker, , op. cit. (9), 168Google Scholar; and Kaiser, , op. cit. (44).Google Scholar

¹⁰⁸ Bohr, , op. cit. (33), 699.Google Scholar

¹⁰⁹ Interview with Niels Bohr, conducted by Kuhn, Thomas S., Petersen, Aage and Rüdinger, Eric, 17 11 1962, p. 11Google Scholar of transcript; copies in AHQP-AIP.

¹¹⁰ A recent issue of Science In Context (1991), 4, 2Google Scholar, focuses on the somewhat problematic term ‘style’ as an explanatory tool in history of science. The collected articles debate the appropriateness of isolating various national, scholastic, and individual styles. (Cf. especially Anna Wessely's criticism of the use of ‘style’, in Wessely, A., ‘Transposing “style” from the history of art to the history of science’, Science In Context (1991), 4, 265–324CrossRefGoogle Scholar.) To be helpful, descriptions of individuals' personal approaches to science in terms of ‘style’ must reflect their personal context: scientists' styles of work cannot be disembodied from their emotional commitments and motivations.

¹¹¹ Buchwald, J., ‘Essay review of Energy and Empire’, BJHS (1991), 24, 87CrossRefGoogle Scholar. The fractal imagery testifies to the robustness of ‘personality’ as a historiographical tool. Its explanatory power derives from the close-knit coherence of an individual's pre-scientific and scientific activity. Whereas ‘genius’ was hoisted by older generations as a means of black-boxing the roots of an individual's scientific activity, investigations of ‘personal context’ open the black-box a little to reveal a constrained system of repeated patterns.

¹¹² Ian Hacking, Peter Galison and Timothy Lenoir object to such theory-dominated accounts of science, and discuss the experimental and technological presuppositions of observations. Cf. Hacking, I., Representing and Intervening, New York, 1983CrossRefGoogle Scholar; Galison, P., How Experiments End, Chicago, 1987Google Scholar; and Lenoir, T., ‘Practice, reason, context: the dialogue between theory and experiment’, Science In Context (1988), 2, 3–22CrossRefGoogle Scholar. The present paper's emphasis upon theory stems from the nature of the Einstein–Bohr debate: both disputants agreed that quantum mechanics was more or less empirically corroborated.

¹¹³ Longino, H., Science as Social Knowledge, Princeton, 1990, 40–4.Google Scholar

¹¹⁴ Rosenberg, C., ‘Woods or trees? Ideas and actors in the history of science’, Isis (1988), 79, 567–8CrossRefGoogle Scholar. Susan Krieger, a sociologist, has remarked that ‘individuality is theoretically unpopular’ in the social sciences as a whole, and argues for more explicit consideration to be paid to the researcher's individuality as well as to the individuality of the people studied. Like Rosenberg, she does not advocate study of the self to the exclusion of social and cultural contexts, but none the less encourages examination of aspects of individual personality and perspectives. Krieger, S., Social Science & The Self, New Brunswick, 1991, 43–5.Google Scholar

¹¹⁵ Quoted in Heilbron, , op. cit. (7), 143Google Scholar. Heilbron paraphrases Planck's view by writing: ‘The final basis, the last authority, for the fundamental principles of physical science lie deep in the individual’ (Heilbron, , op. cit. (7), 143).Google Scholar

¹¹⁶ A compelling historical portrait of this sort of fundamental person-hood is given by McCormmach, R., Night Thoughts of a Classical Physicist, Cambridge, Mass., 1982.Google Scholar

¹¹⁷ Moore, , op. cit. (4), 395Google Scholar. Cf. Pais, , op. cit. (16), 12–13.Google Scholar