1 Introduction
During the decades after the Second World War, the relationship between science and National Socialism was generally portrayed in one particular way: science had remained apolitical and objective, but had been exploited and abused by Hitler’s regime.Footnote 1 Cracks in this edifice began to develop in the 1970s and early 1980s, perhaps best illustrated by the “Health Day” held in Berlin in 1980 as a counter-event to the official German Physicians’ Conference (Baader Reference Baader and Schultz1980). The alternative gathering opened with the theme: “Medicine and National Socialism: Taboo Past, Unbroken Tradition?” and questioned whether National Socialist medicine and science had really been hostile towards one another. Herbert Mehrtens was in the vanguard of the critical scholars who began scrutinizing the relationship between science and the National Socialist state at this time. Indeed Mehrtens arguably created the historical field studying science, medicine, technology, and National Socialism (Siegmund-Schultze Reference Siegmund-Schultze2022).
“The ‘Third Reich’ in the History of Science,” Mehrtens’ first, groundbreaking essay on the history of science during the National Socialist period in Germany (including some discussion of Weimar), surveyed the available sources in order to show what was already known and outline the limits of this literature, and then went on to detail where new research was needed (Mehrtens Reference Mehrtens1980). At the time, serious critical work meeting the standards of historical scholarship did not include much beyond the books of Karl-Heinz Ludwig on technology and engineers (Ludwig Reference Ludwig1974) and Alan Beyerchen on the physics community (Beyerchen Reference Beyerchen1977). The available literature instead often consisted of memoirs and hagiography that portrayed a black-and-white dichotomy between “Nazis” and serious scientists. Mehrtens’ Reference Mehrtens1990 chapter on “Irresponsible Purity” used examples from mathematics and physics to demonstrate the problematic consequences of an “apolitical” stand by mathematicians and scientists in a regime like Germany under National Socialism (Mehrtens Reference Mehrtens, Renneberg and Walker1994b). Finally, Mehrtens’ essay on “Collaborative Relations” represents his last word on science and technology during National Socialism and how historians have grappled with it (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c). Mehrtens’ use of the powerful word “collaboration” captured, in a nutshell, the transformation that had occurred or was occurring in many of the best studies of “science under Hitler”: rather than seeing Nazis and anti-Nazis fighting against them, Mehrtens very often saw scientists and non-scientists working together within the National Socialist state. In a real sense, Mehrtens broke through the existing wall of apologia, especially in the German language literature.
2 Reconstructing the historiography of science and mathematics in National Socialist Germany
2.1 Historiography
The 1978 meeting of the German Society for the History of Medicine, Science, and Technology included, for the first time, a series of talks on National Socialism. Some of these were subsequently published as a small collection of essays. The literature existing at that time was analyzed by Mehrtens in a historiographic essay that helped define the study of science, medicine, and technology under National Socialism. What is perhaps most impressive about Mehrtens’ historiographic survey is his ability, like the contemporary work of the political scientist Joseph Haberer (Haberer Reference Haberer1969), whom Mehrtens approvingly cites (Mehrtens Reference Mehrtens1980, 34), to work with a flawed set of sources, including memoirs, hagiography, and works of history that repressed rather than illuminated the interaction between science on one hand and National Socialism on the other. Through the use of a penetrating, critical, and sometimes skeptical analysis, Mehrtens nevertheless drew out the important questions to be asked.
Mehrtens directly confronted what he described as “coping literature” (Bewältigungsliteratur) and the various “dissociation strategies” employed by scientists, the most common of which was the separation of science from its misuse. According to the biologist Georg Melchers, for example, science was not responsible for its abuse, even if scientists were responsible (Mehrtens Reference Mehrtens1980, 35, 38). But Mehrtens, at that time at the very start of his academic career, also did not shy away from critiquing the most important and influential contemporary scholarly works in the history of science and technology during National Socialism. For instance, while acknowledging that Alan Beyerchen’s book Scientists under Hitler was a “pioneering work in the historiography of science” (Mehrtens Reference Mehrtens1980, 18), Mehrtens noted that it focused on prominent scientists and took them as representative of the discipline. Thus the “Aryan Physics” group was thoroughly analyzed, but everyday routines in the laboratories and lecture halls were hardly mentioned; and the connections between physics and industry, as well as the significance of war-related research, were not investigated. For Beyerchen, “physics” was limited to fundamental research, and the connections to the periods before 1933 and after 1945 were deemphasized. This had consequences for his interpretation: “Just as physics is portrayed as socially isolated and represented by the fundamental research of ‘great scientists,’ so National Socialist rule in Germany appears as an isolated epoch, which can also be handled in an isolated way” (Mehrtens Reference Mehrtens1980, 19).
Mehrtens similarly engaged critically with the other major book existing at that time: Karl-Heinz Ludwig’s book Technology and Engineers in the Third Reich. Although it was the best existing account of science policy in the National Socialist state, Ludwig explicitly limited himself to empirical history and rejected a “theoretical treatment that investigates the causes, structures, and consequences of Fascism in power” (Mehrtens Reference Mehrtens1980, 23). Here, Mehrtens is using “Fascism” as a synonym for National Socialism. Ludwig, Mehrtens argued, also left open an important question for engineering that was also relevant for science: how did technology and science develop between 1933 and 1945, and what role did National Socialism play (Mehrtens Reference Mehrtens1980, 23–24)? Mehrtens’ analyses showed that, in fact, Beyerchen and Ludwig did not transcend the problematic black-and-white divisions of the more apologetic literature. Their work describes a polarized world in which the majority of scientists and engineers restricted themselves respectively to science and engineering, while a minority of others were political and ideological.
2.2 Calls for a Social History of “Science under Hitler”
Published in 1980, Mehrtens’ analysis is a reflection both of its time—when the world was separated into capitalist and communist spheres, perhaps most dramatically represented by the wall running through the city of Berlin where the author lived—and of Mehrtens’ own interest in Marxism. Although the explicit Marxist language and imagery he employed in this essay is absent from many of his later publications, Mehrtens’ concern with structural analyses of science in the modern industrial state remained. In another publication, Mehrtens provides a definition for the social structure of mathematics that can also be used for science, noting that the “central function” of “the social system of the discipline” was “producing and disseminating novel knowledge of a specific character” (Mehrtens Reference Mehrtens, Renneberg and Walker1994a, 291–292). Scientific disciplines, he adds, exchange their “knowledge products plus political loyalty in return for material resources plus social legitimacy,” concluding that the social system “knows nothing of morals and politics, and its representatives in general act accordingly” (Mehrtens Reference Mehrtens, Renneberg and Walker1994a, 292, 303–304).
Mehrtens made clear that he would not approach his subject in the traditional way as intellectual history, which in fact had sometimes been used to distance science and scientists from the politics and ideology of National Socialism. Instead, his “perspective is one of a social history of the sciences that investigates the social structure of scientific work, its role in the development of society, and the social conditionality of the history of knowledge,” including, in particular, “the position of science and its representatives between the state and industry” (Mehrtens Reference Mehrtens1980, 15). Mehrtens called for a comprehensive investigation of the “socialization” of science, whereby science would not be narrowly defined as fundamental research. Instead, science should be analyzed as a social subsystem in which knowledge about nature is produced, traded, and propagated. This would mean seeing science as part of the economic system as well as of culture (Mehrtens Reference Mehrtens1980, 40–41).
2.3 The integration of science and mathematics into National Socialism
The question of whether National Socialism contributed to the modernization of German society, an important historiographic question at the time, and one that is still debated, led to investigations of the interaction between science and technology on one side, and National Socialist ideology on the other. Mehrtens put forward the thesis that science could be integrated into Fascist society in two different forms: (1) by means of “Aryan science” (völkische Wissenschaft) like “Aryan Physics” or “Aryan Mathematics”; or (2) science in the service of “national tasks” for “all people” (Volksganze), a term which of course actually referred only to individuals whose race and conduct were acceptable to the National Socialist state. He noted that the existing literature at the time only recognized the first category as having been affected by National Socialist ideology, because the advocates of an “Aryan science” had sometimes called into question the very foundations of science.
Although “Aryan science” was “virulent” during the first years of the regime, it was subsequently superseded by the slogan of science “in the service of the people” (Dienst am Volk). Moreover, as Mehrtens pointed out, under the conditions of Fascist rule this was also ideological (Mehrtens Reference Mehrtens1980, 44–47). A portion of Germany’s scientific capacity was certainly damaged and some developments hindered by incompetence, lack of cooperation, and the expulsion of Jews and political opponents of National Socialism from their positions, but Mehrtens made the important observation that in many areas the remaining scientific potential was intensively used and expanded further. Beginning in 1936, as science was increasingly integrated into the rearmament effort, scientists were able to use their “service to the German people” as a lever to increase their scientific autonomy (Mehrtens Reference Mehrtens1980, 62, 64).
Mehrtens’ criticism of “mastering the past” (Vergangenheitsbewältigung), a term that has subsequently been superseded by “the politics of the past” (Vergangenheitspolitik) (Frei 1999) is refreshing in its clarity and precision. Physics, the science that was the most studied, had been portrayed as the paradigm for a “pure science,” including its “fall from grace” as personified by the atomic bomb. As far as resistance to National Socialism within the ranks of physicists and other scientists was concerned, Mehrtens noted there was “little to report” (Mehrtens Reference Mehrtens1980, 16–17). In fact, he added, “the struggle over the autonomy of pure science led to collaboration with Fascism” because “under the conditions of the ‘Third Reich,’ defending the ‘purity of research’ … was a political act” (Mehrtens Reference Mehrtens1980, 66–67). “When this was connected with support from IG Farben or Army Ordnance,” he pointed out, “this was an act of collaboration” (Mehrtens Reference Mehrtens1980, 67).
3 Critique of “irresponsible purity”
Ten years later, Mehrtens noted that “political self-criticism” regarding the activity and structure of scientific institutions is neither practiced nor welcome. In a striking passage, Mehrtens described how:
During a discussion at a large research institute, I have experienced how a scientist, who was partly responsible for a critical counter-Festschrift for the anniversary of the institute, was subtly but clearly threatened by the head of the institute. Anyone who uses his time in such a way, he was told, could hardly be a good scientist, because he is not concentrating sufficiently on his proper work. In a letter of recommendation such a statement can have a disastrous effect on a scientific career. In addition, up until that time the institute head had considered this individual to be a “good scientist.” The reason for this threat was a controversy over the history and structure of the institute. (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 327)
At the time this was published, Mehrtens’ critical scholarship appeared to threaten his own academic career, in retrospect making this description appear autobiographical.
In his 1990 essay, Mehrtens juxtaposed two mathematicians, Ludwig Bieberbach, who opportunistically embraced National Socialism after Hitler’s movement came to power, and Emil Julius Gumbel, a pacifist, political activist, and applied mathematician who published statistical analyses of right wing violence during Weimar before he went into exile, to illustrate the two extremes of the spectrum of possible responses by mathematicians to National Socialism. Mehrtens emphasized that it is important to analyze how the mathematical community remembers both men. Bieberbach is known for both his “Aryan mathematics,” an example of the “bad politicization of mathematics,” and his contributions to “pure” mathematics. Bieberbach is worth remembering “as a mathematician,” but Gumbel is not. This is a typical example of how the collective memory of science—not just mathematics—produces the “picture of the pure scientist” (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 324–325).
Mehrtens argued that, while responsibility can be expected of individuals and moral judgments of them are meaningful, an institution or social system has its ethics in the institutional arrangement and in norms for language and conduct, rendering moral judgments of science or mathematics meaningless. Instead the question should be: “how science determines the self-image and conduct of the scientist” (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 326). Mathematics defines itself in an extremely restrictive fashion: to do mathematics, to be a mathematician, is identified exclusively by the process and result of the research-oriented mental investigation of mathematical problems. This turns mathematics into something “apolitical and amoral” (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 328). When scientific knowledge is described as “pure” and true research a “silent garden,” these are apologetic claims of purity. As Mehrtens observes: “If a Nazi bureaucrat involved in the extermination machine were to refer to the purity and neatness of his index-card system, we would be horrified at the banality of evil” (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 329).
The collective memory of a discipline or profession is part of its mythology, the “framework of symbols and meanings, in which the common self-understanding, the social identity, is contained” (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 327). Whereas Bieberbach functions as a negative symbol—“the bogy-man, who causes fear and is defended against, [and] is the one with scientific authority and bad politics”—the counterpart, someone who would combine scientific authority and responsible politics, does not exist (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 327). Gumbel would be a suitable symbol for this, but the mathematical community has forgotten him. His mathematics was not profound enough and his political activism unwelcome, if not almost an embarrassment.
Heeding his own call for the theoretical analysis of the social history of science, Mehrtens presents six theses regarding science as a social system. Here these theses are paraphrased, not directly quoted:
First thesis: The social system of a mathematical science defines itself through the process and product of work in pure research as an exclusively cognitive entity.
Second thesis: The restrictive self-definition of the discipline justifies a special interest politics (Interessenpolitik) that obscures political or moral considerations, so long as they do not immediately concern the productivity of the discipline.
Third thesis: By means of their self-definition and the resulting special interest politics, the scientific disciplines made themselves independent to a considerable degree from changes in their political surroundings.
Fourth thesis: The scientific disciplines, including mathematics, are systems with complex internal differentiations, in which applied or demand-oriented sciences in different forms have their place as well as special interest politics and public work. The restrictive, cognitive self-definition of science can conceal the internal differentiation both internally and externally.
Fifth thesis: The sciences ensure themselves public legitimacy and limited access to social power through accommodation to specific power relationships and through their exploitation of antagonisms in the systems of social power. In addition, the natural sciences take advantage of the classical strategy of professions, to monopolize their competence as much as possible.
Sixth thesis: the natural sciences and mathematics produce potential means to power. They deliver technically and socially valuable knowledge. That is the decisive basis for their existence, also in the National Socialist state. (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 331–335)
“Pure” science is politically irresponsible because these disciplines are in fact socially organized and therefore “political through and through” (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 336). A science that instead wanted to be politically responsible would have to be able to see itself as it actually is, and to realistically consider the consequences. In other words, it would have to recognize its own impurity. For this reason, Mehrtens argues that science must be politicized. The conditions and goals of research as well as its social structure and interests must be discussed and critiqued, first for the specific local work situation, and also globally for the relationship between the systems of science and politics (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 337).
4 The collaboration of science with political ideology
Mehrtens’ 1994 essay originated from another meeting of the German Society for the History of Medicine, Science, and Technology in the autumn of 1992. This one, however, differed from the 1978 meeting in several ways (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c). Three years after the fall of the Berlin Wall, the society met in the east German city of Jena as Germans were struggling with the challenges of unification. Overshadowed by the legacy of Communist rule in East Germany, the main theme of the meeting was science, medicine, and technology during the National Socialist period. Mehrtens himself was now a professor at the Technical University of Braunschweig and the keynote speaker.
Mehrtens urged his audience and readers to pursue the comparison between National Socialist Germany and the German Democratic Republic, including questions of continuity and comparing the different political systems, but to do this carefully. Comparisons between the unification process then proceeding and the National Socialist “coordination” (Gleichschaltung) were “sometimes shockingly quick and superficial” (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 13). Having been present at this conference, I remember a prominent west German historian of science, someone hardly known for critical analysis of science during the National Socialist period, standing up in the audience during a different session of the conference and telling the assembled historians from East and West that west German historians could study the effects of communist ideology on science because “we already know how to do this.”
For Mehrtens, with his emphasis on the social history of science, the point of such comparative analysis would be “the problems of the structures of rule and of social integration,” which clearly begged the question of the “integration of the technical-scientific experts and their role so-to-speak in the middle management of society” (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 14). Such investigations needed to be self-critical, for scholars who study science under National Socialist rule need to recognize that they, as historians working in a scholarly enterprise within a particular and dynamic society, were also “politically dependent,” and must therefore be aware of “where we are able to act and where we are helpless” (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 14).
Drawing upon the examples of two prominent and influential scientists, the physicist Max Planck, also president of the Kaiser Wilhelm Society, and the aerodynamic researcher Ludwig Prandtl, Mehrtens notes that they were “loyal to and carefully accommodated” themselves to the National Socialist state (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 20). This type of accommodation, whereby state policies are assumed to be legal, combined in a complex way with nationalistic and National Socialist activism, careerism and the culture of denouncement, professional self-restriction and special interest politics, in order to subordinate and integrate scientists into the National Socialist state and encourage the “self-coordination” of the universities and other scientific institutions (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 20).
Mehrtens then examined several prominent postwar examples of physicists unrepentantly and apologetically presenting improbable and distorted images of science under National Socialism.
Here two very German words are used for physics: “clean” (sauber) and “decent” (anständig). Different from in English or French, in German “sauber” means freedom from dirt and vermin as well as moral purity. The rhetorical figure of separation into good and evil (Gute und Böse), which along with cleanliness (Sauberkeit) also implies purge, is not so dissimilar from “racial purity.” How can scientific physics be “decent?” Methodically correct work is taken as having a moral value in the political discourse on the National Socialist past. (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 17)
Because data gathered from the murderous “Gypsy” research had been used in anthropological scientific research in postwar West Germany, and data from the murderous concentration camp experiments had entered the international psychological literature, this data must have been “scientific.” Indeed, Mehrtens argued that:
We have to recognize that science is as human as mistakes, war, or crime. That science in practice should not be inhuman is a reasonable ethical precept. To claim … that this is the essence of science, means relief and repression; the ethical responsibility is delegated to the higher “essence.” (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 18)
Mehrtens rejected the often-used phrase, the “‘abuse’ of science, with its echoes of sexual abuse and raped innocence” (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 24). Scientists collaborated with National Socialism wherever the experts were needed; where the utility of scientific work was not readily obvious, for example in the example of theoretical physics, scientists “offered to make a new, grandiose energy technology [nuclear power] for the political leadership” (Mehrtens Reference Mehrtens, Meinel and Voswinckel1994c, 24).
5 Herbert Mehrtens’ enduring influence on the historiography of science and National Socialism
With his groundbreaking 1980 literature survey, his courageous critique of scientific “purity,” and his final call for a “politicization of science,” Mehrtens has had a profound influence on historians of science, medicine, and technology who study National Socialism. As Mehrtens realized, the previous focus on the internal content of a scientific discipline allowed an abstraction away from the social realities of National Socialism. Although it is certainly possible to do critical disciplinary history of science under Hitler (Deichmann Reference Deichmann1996, Reference Deichmann2001), the fact remains that a concentration on intellectual history and narrowly-focused disciplinary activity has allowed some scientists, their apologists, and hagiographers to obscure or ignore the consequences of practicing science during National Socialism and the Second World War.
The consequential turn towards a social history of science in order to understand the National Socialist period can be seen clearly in the nearly decade-long large-scale research project financed by the Max Planck Society on the history of the Kaiser Wilhelm Society under National Socialism (KWGNS Project) (Ash Reference Ash2010; Heim, Sachse & Walker Reference Heim, Sachse, Walker, Heim, Sachse and Walker2009). The general focus of the project was not how physics, biology, aerodynamics, or other branches of science and technology developed between 1933 and 1945 in Germany, but how scientists, scientific institutions, and research programs intersected and interacted with the goals and policies of the National Socialist state.
Although there are far too many examples to list here, and not all the publications subsequently mentioned come from the KWGNS Project, Mehrtens’ call for a structural analysis of science in the modern industrial state and the inclusion of war-related research was answered by work on a plethora of topics (Maier Reference Maier2002, Reference Maier2007b), including aeronautics (Eckert Reference Eckert2019; Trischler Reference Trischler1992), rocketry (Neufeld Reference Neufeld1995, Reference Neufeld2007), and especially metals research (Maier Reference Maier2007a). These works demonstrated that, during the periods of rearmament and war, if not also before, there was a deep-rooted, pervasive, and far-reaching cooperation between scientists and scientific institutions, engineers, and German industry.
Mehrtens’ concept of “irresponsible purity” is perhaps most suggestive when some of the most disturbing research done during the National Socialist period, sometimes called “science without moral boundaries,” is investigated. Scholars have developed a much deeper understanding of the roles played by scientists in the “Germanization” of occupied territories and the exploitation of human subjects in research in concentration camps and elsewhere (Aly & Heim Reference Aly and Heim2002; Eckart Reference Eckart2012; Heim Reference Heim2008; Roelcke Reference Roelcke, Rubenfeld and Benedict2014; Sachse Reference Sachse2003; Schmuhl Reference Schmuhl2003, Reference Schmuhl2008). Mehrtens’ work also inspired analysis of scientific institutions as intermediaries between scientists and the state: while individuals can behave politically and (im)morally, institutions are apolitical and amoral and sometimes thereby facilitated National Socialist policies (Sachse & Walker Reference Sachse, Walker, Sachse and Walker2005). The general thrust of all this work is that when moral boundaries were loosened, there were scientists willing and able to take advantage of these opportunities.
The image of science and mathematics that Mehrtens developed over the course of his career is one of the seamless integration of scientists and mathematicians within the National Socialist state, breaking down the false barriers between researchers on one side, and ideologues and perpetrators on the other. This was a complete rejection of the prevailing understanding in 1978, now revealed to be an apologetic, self-serving caricature of science separated from both ideology and politics, and scientists separated from Nazis. His term for this, “collaboration,” has been a challenge to scientists and historians of science alike, capturing the essence of the relationship between scientists and National Socialism, and providing fertile ground for subsequent historians to build upon and refine his critical analysis.
Scholars have scrutinized individual scientists and mathematicians like Planck (Albrecht Reference Albrecht and Albrecht1993; Heilbron Reference Heilbron2000; Hoffmann Reference Hoffmann2008), Prandtl (Eckert Reference Eckert2019), Bartel van der Waerden (Siegmund-Schultze Reference Siegmund-Schultze, Hoffmann and Walker2011) and Werner Heisenberg (Cassidy Reference Cassidy2009; Carson Reference Carson2010; Walker Reference Walker2024), as well as scientific institutions including the chemical (Deichmann Reference Deichmann, Hoffmann and Walker2012; Maier Reference Maier2015), physical (Hoffmann & Walker Reference Hoffmann and Walker2012), and mathematical societies (Remmert Reference Remmert, Hoffmann and Walker2012). Mehrtens’ most important contribution to the historiography of science, mathematics, medicine, and engineering during the National Socialist period was arguably his observation that science justified as “in the service of the people” could and did develop into a mutually beneficial collaboration with National Socialism. This was the essence of the KWGNS project and has perhaps been best further developed in the model of “science and politics as resources for each other” (Ash Reference Ash and Bruch2002, Reference Ash, Bruch, Gerhardt and Pawliczek2006).
Last, and perhaps most controversial, was Mehrtens’ claim that “science must be politicized” (Mehrtens Reference Mehrtens, Renneberg and Walker1994b, 337). His trenchant criticism of the scientific community’s “mastering the past/politics of the past” (Mehrtens Reference Mehrtens1980, 16–17) inspired other scholars to transcend the boundary of the end of the Second World War and investigate both how scientists justified, obscured, or denied their respective collaboration with National Socialism, as well as how this apologia has subsequently influenced the reconstruction of science in Germany, including up to the present day (Hentschel Reference Hentschel2007; Rammer Reference Rammer, Trischler and Walker2010, Reference Rammer, Hoffmann and Walker2012; Sachse Reference Sachse, Heim, Sachse and Walker2012; Sime Reference Sime2012; Schüring Reference Schüring2006; Walker Reference Walker1990, Reference Walker2024).
Mark Walker is the John Bigelow Professor of History at Union College, where he teaches modern European history and the history of science and technology. His research and publications have focused on the history of science and National Socialism, with his first and most recent books devoted to the “German atomic bomb.”
