Dialogical Emergence Versus Rhetorical Consolidation

pilot-wave equation needs not be solved, problems with ontological parsimony emerge. In 1927, to be sure, they might have been counterbalanced by ontological conformity, but today this strategy is not viable.

Cushing’s counterfactual is thus no sufficient reason to investigate the Bohm theory. But to my mind, it is not necessary as well. The pragmatic score sketched above was not hopeless. Moreover, the Bohm theory provides a very interesting model that the quantum mechanical formalism – now denoting all basic concepts and equations – can be modified in certain non-trivial ways without changing the empirical content. Against the backdrop of the philosophical analysis of scientific theory as developed since the 1920s, this seems already a sufficient motivation to study this alternative.

In this perspective basic papers – or rather: master texts – exhibit an irreducible polyphony.

First, Heisenberg’s uncertainty paper (1927) was full of challenges, doubts, and contradictions on all levels above and beyond the mere formulas.

[Philosophically] contradictory voices of positivism (operationalism), model theoretic realism (the invariant features of a successful scientific theory refer to genuine aspects of reality), and conventionalism (physicists can freely choose the basic axioms of a theory, worrying only about its consistency and empirical adequacy) are all present in Heisenberg’s paper. (Beller, 1999, p. 104)

Already two years earlier, Heisenberg’s efforts were not guided by a “coherent philosophical choice between positivism and realism” (Ibid., p. 52), but there prevailed a peculiar mixture of “the positivist, identifying the meaning of a concept with the procedure for its verification (in real or imagined physical interactions [like the microscope thought experiment]), and the realist, deducing the genuine features of the quantum world from characteristics of the mathematical formalism.” (Ibid., p. 113f.) Yet for Logical Empiricists, these two voices in Heisenberg were not inconsistent; in his “Positivism and Realism” Schlick (1932) argued that who accepts the verificationist criterion of meaning has not problem with realistically interpreting certain terms in the formalism.

Second, Bohr’s Como lecture (1927) “was not the resolution of wave-particle duality by the complementarity principle but rather an extensive defense of his concept of stationary state and discontinuous energy changes.” (Beller, 1999, p. 118) What appears as “one of the most incomprehensible texts in twentieth-century physics”

(Ibid., p. 8) is in fact “filled with implicit arguments with the leading physicists of the time – Einstein, Heisenberg, Schrödinger, Compton, Born, Dirac, Pauli, and the lesser known Campbell.” (Ibid., p. 120) In this way the “deep conceptual gap fundamental between Bohr’s wave-theoretical and Heisenberg’s particle-kinematic interpretation of atomic systems” (Ibid., p. 122) becomes evident. This gap “is one of the historical roots of the inconsistencies that plague the Copenhagen interpretation of physics”

(Ibid., p. 122) to date. Yet the united front had to be established very quickly to meet the challenge of Schrödinger’s intuitively appealing and technically superior formalism. “In his Como lecture Bohr [also] set the historical record straight … [and]

presented matrix mechanics as the culmination of his own research program, based on the correspondence principle.” (Ibid., p. 141) Heisenberg complied with Bohr’s leadership and thus the orthodox narrative was instituted.

The strongest challenge to the Copenhagen dogma was the Einstein-Podolsky-Rosen paper (1935) which struck the already consolidated Copenhagen hegemony by surprise. Repeating the successful rhetorical move of 1927, in Bohr’s reply “sincere and open-minded, though interest-laden, interpretative attempts hardened into an ideological stand intended to protect quantum theory from challenge and criticism.”

(Beller, 1999, p. 9) The paper marked the “transition from legitimate, though often confused arguments for the consistency of quantum theory, to argumentative strategies promoting the inevitability of the orthodox stand.” (Ibid., p. 9) The year 1935 separates two voices: reference to Heisenberg’s idea of physical disturbance fades away because EPR had made it untenable, while the “emerging operational voice will culminate in unreserved verificationism.” (Ibid., p. 151) Bohr’s account of the EPR paper introduced philosophical weaknesses not existing in the original. While in the

EPR paper “the elements of physical reality are the physical variables that can be predicted with certainty, … Bohr reformulated the passage from EPR into a metaphysical discussion of what physicist mean when the say ‘reality’. This reformulation … had a strong rhetorical effect.” (Ibid., p. 154) Einstein appears as the outmoded naive realist, which – of course – he is not. Eight years further down the historical road, we find again the conundrum of Einstein’s realism which as of 1927 was the linch pin of Cushing’s counterfactual.

Thus the “Copenhagen interpretation was erected, not as a consistent philosophical framework, but as a collection of local responses to challenges from the opposition.” (Ibid., p. 167) Copenhagen’s formal consistency was elevated to its inevitability and to the finality of quantum mechanics. In the subsequent years, “the opposition’s stand is delegitimized and trivialized” and “the past is manipulated to make the winners look naturally right.” (both ibid., p. 10) Beller classifies this shift by adopting terminology from the influential lecture course of Nobel laureate Richard P.

Feynman (Feynman/Leighton/Sands, 1969)

In the two-slit experiment, one “need not” assume that the particle traverses a well-defined path between the two-slit diaphragm and the detector. … “Need not” is an integral part of scientific practice, without which such breakthroughs as the rejection of absolute simultaneity in relativity theory and the rejection of a strict determinist framework in quantum theory would not have been possible. “Must not” is a positivist excess, at odds with the practice of science, which relies on realistic models as a heuristic guide to discovery. (Beller, 1999, p. 174)

The allegation that positivism hampers scientific progress is not new. Planck threw it against Mach (Section 3.7.), Sommerfeld against Frank (in a letter to Schlick), and it notoriously suffered from a restricted view on the target. But the dichotomy is well-suited for the “scientific pugnacity” so heavily criticized by Neurath (1915).

While the microanalysis in the first part of Beller’s book – though on a different methodological basis – complies with Neurath’s advice that historians of science should investigate all intermediate positions, the second part itself lives such pugnacity and rides a rhetorical counterattack against the Copenhagen dogma. Instead of the dialogical microperspective, now the orthodox narrative is put against the backdrop of its few critics, above all David Bohm and John S. Bell. Historical succession is dissolved; pronouncements of Bohr and Heisenberg are contrasted with criticism made much later.⁴⁰ The rhetoric appeal of antirealism as a strategy to protect science and to appease internal conflicts are discussed against the backdrop of P.W. Bridgman’s operationalism (Beller, 1999, pp. 176-180) instead of mentioning any realism debate concurrent with the emergence of the Copenhagen interpretation in Europe. In the end, Beller consequently does not arrive all too far from Cushing’s counterfactual outlook, and her plea for an alternative interpretation faces the same methodological problems as shifting criteria of theory preference back and forth in history.

The most disturbing feature of Beller’s presentation is the harsh and sometime derogatory rhetoric – somewhat reminiscent of Forman (1971). Among the bad guys is Heisenberg whose “hostility to Schrödinger’s theory seems more likely to be connected with his instinctive reluctance to admit anybody else into territory that the ambitious Heisenberg considered his own.” (Beller, 1999, p. 32) In his recollections

Heisenberg transgressed the subtle line between “manipulation of history and deliberate deception.” (Ibid., p. 213) But the really bad guy is Bohr. “As is suitable for a prophet, Bohr talked in fables and parables.” (Ibid., p. 244) Being “an avid storyteller” (Ibid., p. 243) but – other than Bohm and Bell – “[l]acking advanced mathematical skills, Bohr could not build a new quantum ontology but instead had to use ‘common language’ and simple analogies. This personal trait, if not weakness, was canonized into the universal doctrine of the indispensability of classical concepts and the impossibility of a quantum ontology.” (Ibid., p. 259) Disabled in his computational capacities, overloaded with administrative duties, depending upon his authority to make his assistants carry out his vague intuitions, despite all “hero worship” (Ibid., p.

153), “Bohr was a tragic figure.” (Ibid., p. 271) “The legend that Bohr had some sort of access to nature’s secrets, qualitatively different from that of other mortals, directly discouraged critical dialogue.” (Ibid., p. 271) In actual fact, this legend was older than the Como lecture or the philosophy of complementarity (See Sect. 4.7.2).

Within her black and white set-up,⁴¹ Beller did not undertake any further investigation why communication was inhibited, although an interesting sociological model is available at least for the case of Bohm and von Neumann which, to my mind, might be suitably adapted. Trevor J. Pinch commences from the following distinction.

The research-area mode of articulation occurs when the disputed object forms part of the particular area of concern of scientists involved in the controversy. … The official-history mode of articulation, by contrast, occurs when the cognitive object is referred to in some other context than the immediate area of concern. … I regard this context as being mainly the production of cumulative history of rationalisation of how a particular field developed. (Pinch, 1977, p. 175)

Bohm’s (1952) proposal challenged the interpretation of quantum mechanics in the research-area mode by producing a counterexample and publishing it in the discipline’s leading journal. On the contrary, “much of the response of the [quantum mechanics] elite has been articulated in the official-history mode,” (Ibid., p. 187) mainly by restating von Neumann’s theorem. Bell’s (1966) counterexample found better acceptance than Bohm’s because he could precisely spot the defect in von Neumann’s theorem and, accordingly, dragged the opponent back into the research-area mode. In the discussions ensuing the EPR-paper, this did not happen – although the paper represented the germ of Bell’s later analysis. At bottom, it appears to me that large part of Beller’s distinction between “dialogical emergence” and “rhetorical consolidation” boils down to the two modes distinguished by Pinch.