Introduction

On April 2, 1922, a film entitled “The Basic Principles of Einstein’s Theory of Relativity” premiered at the Frankfurt Trade Fair.1 This film is virtually unknown today and seems to have been lost: Of the two-to-three-hour film only a thirty-minute excerpt has been preserved.2 Two of its fascinating aspects are, first, that no other educational film in science reached such a wide audience at the time, and second, that no other educational film in any area was so controversial and discussed by such a broad cross section of German society.

My main focus here is not the film itself, but to examine how this educational film became a box-office hit and simultaneously the subject of heated public debate. I first sketch the making and content of the film and then clarify some aspects of the public controversy it generated. My discussion and analysis is based on a collection of thousands of newspaper clippings that the physicist Ernst Gehrcke (1878–1960) assembled in the early 1920s.3 Gehrcke, a fierce opponent of Albert Einstein’s theory of relativity, attempted to use these newspaper clippings to expose the success of Einstein’s theory as a result of the “mass suggestion” that the “propaganda” of the daily press induced in the German public.4 He organized these newspaper clippings thematically in folders containing over seventy reports on the “Einstein film.”

The Making of the Film

The “Einstein film,” as it was called for publicity purposes before Einstein (1879–1955) asked the film company to choose “a more fitting, objective title,”5 was the brainchild of Hanns Walter Kornblum (1878–1970, figure 1), the former director of the educational film department of the German Film Society (Deutsche Lichtbild-Gesellschaft, Deulig), who became committed to its production. It seems that neither Deulig nor other established film companies with educational-film departments, such as Universum Film AG (Ufa), wanted to produce a film about Einstein’s theory of relativity, presumably because of the financial risks involved in such an undertaking. For this reason, Kornblum founded the Colonna Film Company (Colonna Filmgesellschaft) in Berlin in 1922 for the purpose of using film to portray “complete scientific fields and theories … of general interest in a logically structured and comprehensible way.”6

Fig. 1
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Hanns Walter Kornblum (1878–1970). Credit: Courtesy of Wolfgang Kornblum and the Munich Film Museum

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Friends and supporters of Einstein encouraged Kornblum’s project. These included the Swiss science popularizer and educational reformer Rudolf Lämmel (1879–1962), who had known Einstein since his early years in Switzerland and had become an enthusiastic popularizer of his theory of relativity;7 the philosopher Otto Fanta (1890–1940), son of Berta Fanta (1865–1918), who had established an intellectual salon that Einstein had attended during his time in Prague (1911–1912);8 the journalist and writer Otto Buek (1873–1966) and the physician and pacifist Georg Friedrich Nicolai (1874–1964), both of whom were among the few who had joined Einstein in signing the pacifistic and antinationalistic “Appeal to the Europeans” (Aufruf an die Europäer) in response to the nationalistic manifesto “To the Civilized World” (An die Kulturwelt) that ninety-three German scientists and other intellectuals had signed on October 4, 1914, shortly after the outbreak of the Great War.9

Exactly what these friends and supporters of Einstein contributed, however, and whether they cooperated in producing the screenplay for the film, is unclear. Correspondence and newspaper reports suggest that the idea of popularizing Einstein’s theory of relativity through the medium of film had occurred to some of them independently, and that several screenplays were circulated. Thus, in 1920 Buek reported to the philosopher Hugo Bergmann (1883–1975) that he had approached Einstein with a screenplay, who read it, but that Buek had then failed to persuade a film company to produce the film,10 and in 1920 Lämmel noted in the journal Die Umschau that he had produced a screenplay, which he believed was used for the film, but without consulting him.11 In 1924, however, Kornblum wrote an article in which he claimed that he and Nicolai were responsible for the main part of the screenplay.12

Einstein himself maintained that he had nothing to do with the film, and a newspaper even reported that he had explicitly distanced himself from it.13 However, on a private sound recording that the Kornblums made to document their family history, ninety-year-old director Hanns Walter Kornblum reported that he had approached Einstein (figure 2) as early as 1919 with the idea of making a film on his theory of relativity, and Einstein had assured him that he would look over the screenplay—provided that this would not be made public.Footnote 1 I will comment later on Einstein’s peculiar behavior here.

Fig. 2
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Albert Einstein (1879–1955) in Bologna, Italy in 1921. Credit: American Institute of Physics Emilio Segrè Visual Archives, Segrè Collection

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Early German Educational Films

The educational film (Lehrfilm or Kulturfilm) in Germany was in its infancy in the 1920s. From 1895, following the invention of cinematography, short silent films were projected onto screens and shown to the public. However, the two major German companies that produced educational films, Deulig and Ufa, were founded only in 1916 and 1917, respectively. In general, educational films constituted a rather small fraction of the films that were produced, and were closely connected to the educational-reform movement that often spread progressive ideas in German society.14 Thus, in addition to the large number of nature films, a substantial fraction of the educational films that were produced in the 1910s and 1920s dealt with the organization of work or personal hygiene. There were a few films on mathematics and physics, but these were often less than a tenth as long as Kornblum’s 2,045-meter film on Einstein’s theory of relativity, and treated more restricted topics such as the Pythagorean theorem (Ufa, 126 meters).15

After Kornblum set up his film company, the success of his new project depended upon the technical feasibility of his ambitious plan. In 1922 his film on Einstein’s theory of relativity was one of the longest educational films ever made; its screening lasted two to three hours, depending upon how many breaks were included for accompanying verbal explanations. It had the longest trick sequences of any film in its genre at the time, some of which were produced using techniques that were developed especially for this purpose (figure 3).16 Last but not least, Kornblum’s film dared to present an abstract field of theoretical physics to the German public, and therefore ventured into entirely new thematic territory for educational films.

Fig. 3
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Hanns Walter Kornblum (1878–1970, right) and his assistants making a trick shot. Credit: Courtesy of Wolfgang Kornblum and the Munich Film Museum

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The physical consequences that followed from Einstein’s theory of relativity, such as the behavior of a body moving at a speed approaching the speed of light, were obviously much more difficult to present than depictions, for example, of “Flowers, Fruits, and Insects” (Ufa, 172 meters), or of “Brown-Coal Mining” (Ufa, 130 meters),17 which may be taken to be representative of the typical German educational film at the time. Relativistic effects were depicted solely by trick shots that had to be portrayed with extreme accuracy. Motions of 0.05 millimeter per picture conveyed by 1,000–2,000 pictures were the norm.18 In all, almost 80,000 individual pictures were required. Pioneering work sometimes had to be undertaken. For example, to describe the vibration of light waves in the ether (a relatively short sequence in the film), experiments were carried out for weeks before filming could even begin.19 Because of such technical difficulties, work on the film extended over one and a half years.20

Content of the Film

Kornblum originally conceived the project as a complete production of Einstein’s theories of special and general relativity, but in the end he and his filmmakers restricted themselves to the basic principles of the special theory. They intended to depict not only relativistic effects, but also, through the new medium of film, to clarify Einstein’s theory for the German public, who despite the publication of numerous popular expositions of it were still awaiting a really clear explanation. To this end, the film was organized into three parts and a supplement.21

The first part, “the principle of relativity,” focuses on the term “relativity,” in particular on the perception of size or shape in different frames of reference, and on the classical principle of relativity. Included is a scene of a punter on a boat, illustrating the absence of an absolute frame of reference for measuring uniform motion. The second part addresses the wave theory of light and the experimental evidence that contradicts it, such as the photoelectric effect. Further, a trick shot of the Michelson-Morley experiment shows that the motion of the earth through the ether cannot be detected. In the third part, Einstein’s theory of special relativity is introduced as a solution to these experimental puzzles. Trick shots attempt to show the relativistic concepts of space and time. For instance, length contraction is depicted by the shortening of a train moving at a speed approaching the speed of light (figure 4). The relativity of time is then explained by showing clocks that are attached to the train and ones that are mounted on a bridge that is crossed by the train. The film shows that the clocks on the moving train tick at a slower rate than those on the bridge. Finally, the supplement uses trick shots to show the general-relativistic effect that made Einstein world famous in 1919—the observation by Arthur Stanley Eddington (1882–1944) of the deflection of starlight in the gravitational field of the sun during a solar eclipse.

Fig. 4
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The depiction of length contraction in Garrett P. Serviss’s book based upon Hanns Walter Kornblum’s film. The stationary train at the top appears to be shortened as shown at the bottom when it is moving at a speed approaching that of the speed of light. Source: Serviss, Einstein Theory (ref. 2), p. 42

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Public Debate

The above sketch shows that Kornblum’s film, “The Basic Principles of Einstein’s Theory of Relativity,” was a carefully structured and ambitious educational film. The response of the German public was extraordinarily enthusiastic, far exceeding that usually accorded to educational films, which generally were not reviewed in the daily press. As the Karlsruher Tageblatt reported on its premiere at the Physical Institute in Frankfurt:

The … presentations had to be repeated for days on end as the rush of visitors from all classes of society was so active. This film aroused a degree of interest that has never been seen before, not just with scholars, but also with levels of society that otherwise have no interest at all in abstract observations.22

The review closed by declaring that this overwhelming response “is indeed proof of how much the Einsteinian question affects our time and how much the desire to learn about this fantastic theory is spreading everywhere.”

In general, the reasons for the enthusiasm of the German public for Einstein and his theory of relativity were multidimensional and complex; I only note that they ranged from the social and political upheavals in postwar Germany, and the cultural environment in Germany in the 1920s, to the fascination with a theory that reformulated the fundamental concepts of everyday experience. Further, sociological and historical studies of the popularization of science have suggested that the public should not be treated monolithically, but instead as a multiplicity of audiences and actors, each having different expectations, knowledge, and attitudes toward science.23

To analyze the reception of Kornblum’s film, I divide the participants in its public discussion in Germany into four groups: (1) people belonging to the film industry and cultural sector; (2) laymen who were interested, for whatever reason, in Einstein’s theory of relativity; (3) scientists and academics who expressed their views on this attempt to popularize modern physics; and (4) opponents who were mainly politically motivated. This clustering is neither exhaustive nor paradigmatic for analyzing the public discussion of all events pertaining to Einstein’s theory of relativity. These included, for example, the antirelativistic lecture series in which Ernst Gehrcke (figure 5) was one of the speakers,24 which took place in the large auditorium of the Berlin Philharmonic in August 1920,25 and the confrontation of Einstein and Philipp Lenard (1862–1947) in Bad Nauheim the following month.26

Fig. 5
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Ernst Gehrcke (1878–1960) around 1903. Credit: Max Planck Institute for the History of Science, Library, Archival Collection

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It does cover, however, the main groups who were involved in the public discussion in Germany of the Einstein film and their motivations.

Film Industry and Cultural Sector

Director Kornblum and the supporters of his project in the film industry were convinced that the German public was fascinated by Einstein’s grand new theory of relativity, but had not really understood it by reading its numerous popular expositions. Kornblum was correct in this, given the doubtful scientific quality of most of them, and because the public approached Einstein’s theory for a variety of motives, but these often did not include a serious attempt to grapple with it, much less to master it. The new medium of film, then, should make Einstein’s theory accessible to all mankind—even to people who did not read about it in books. Kornblum made this clear in an interview when he stated:

There are two groups of people who have mistaken views about the theory of relativity because they are not used to thoroughly comprehending a problem. The first group has never read about Einstein or his research results, and the second group has read only a little about it and still hasn’t understood the little that they have read. This film comes across as a comprehensible but thorough commentary … for both groups.27

Oskar Kalbus (1890–1987), the scientific consultant (Wissenschaftlicher Referent) of the Educational Film Department of Ufa, expressed a similar opinion in the film journal Kinematograph:

Kornblum … has presented the German educational film industry with a masterpiece. … I sincerely wish that it succeeds in every respect in satisfying the general interest and thirst for knowledge using film, that modern aid for instruction and explanation, and makes Einstein’s theory common knowledge for all mankind.28

Another factor was that Kornblum’s film was regarded as a “German cultural product” and therefore as a means for the cultural and moral reconstruction of Germany after the Great War. Thus, Werner Schwartz of the German Art Association (Deutsche Kunstvereinigung) reflected on the current desolate state of German culture and remarked:

The filming of the basic principles of Einstein’s theory of relativity was joyful news, and hopefully the film has stimulated people somewhat to learn about other scientific innovations. … In these difficult times, Germany needs encouragement, revitalization, strength, and improvement! To be allowed to contribute to reviving the confidence, vigor, and spirit of the Germanic people, that would be a veritable divine objective of German art!29

People from the German film industry and cultural sector thus were motivated, on the one hand, by pedagogical concerns: Einstein’s theory of relativity was viewed as something so fundamental that all laymen should grasp at least its main features and appreciate its significance. Further, they hoped that the public would be inspired by educational films in general, since they were still not sufficiently established and needed support: Educational films accounted for only two percent of all films shown in the German cinema.30 On the other hand, these same people were motivated by political concerns: They hoped to achieve international prestige with this “German cultural product,” which corresponded to the widespread postwar conviction among Germans that they could at least be proud of German culture and science, and hope that Einstein’s theory of relativity would help Germany regain its former standing in international relations, both in science at a time when German scientists were being boycotted,31 and in the political realm.

Thus, as far as the German film industry and cultural sector were concerned, the Einstein film was associated with pedagogical and political expectations that far exceeded those of other German educational films. This was also true, to an even greater degree, for the general public.

Laymen

Laymen commented explicitly in several articles on the questions: “Why am I interested in the theory of relativity?” and “Why am I going to see the Einstein film?” These questions are central for an understanding of the film’s success and in general for the public reception of Einstein’s theory of relativity in Germany. They were discussed in several newspapers, for example, in the Württemberger Zeitung:

How can the general interest in the theory of relativity shown by the wider public be explained? It is certain that Einstein has shaken the foundations of our common worldview and, aware of it or not, has stirred our hearts so that we feel insecure on this tiny earth that always had appeared so solid. This insecurity about world affairs explains the longing to be able to reason for oneself, to know exactly the meaning of these notions that turn our world upside down, and to find our feet planted firmly back on the ground. Hence this overwhelming thirst for knowledge about Einstein’s theory of relativity. Because of this general interest, the Colonna Movie Company decided … to use the film as the best and newest aid for making the theory of relativity general knowledge for mankind.32

The average cinema audience, however, was hopelessly overwhelmed and lost when viewing the Einstein film, as was expressed mainly in satirical articles. Thus, Kornblum’s film was screened in the Swabian Urania (Schwäbische Urania), a society for the popularization of science, and discussed in an article in the Württemberger Zeitung entitled “Einstein’s Film Sensation.” The “voice of the people” reported:

I expected all kinds of things – all the “relativities,” all the scenes that move me: love scenes, murders, homicides, escapes and chases, up hill and down dale, until finally the relative villain is caught, hanged, or beheaded, and the tragic lovers either take poison and die (which is quite horrific) or go to the registry office and marry (just as horrific). But nothing of this kind occurred in the Einstein film. Instead, events and images appeared that made my head spin, so that I no longer knew if I was quite all right, or just relative. In any case, one must be considerably saner than me to understand Einstein.33

The following observations were made in the Berliner Lokal-Anzeiger under the caption, “Relativity Filmed—Impressions of a Previously Clear Layman’s Mind”:

The accurate clock … plays an important role in the explanation of the theory of relativity. We are shown that a clock on the street indicates a completely different time than a clock carried by a man riding the subway. … And if I mention finally that the same train can, at the same time, be twelve, eighteen, and then finally even twenty-four meters long, and that all these measurements are correct, I will probably, like the film, have given the layman an illustrative description of the most famous of all theories.34

Comments on the film by nonacademics were often satirical, citing its failure to provide a clear introduction to Einstein’s theory of relativity. Other commentators welcomed the film as a noteworthy attempt to bring Einstein’s theory to large audiences, emphasizing, however, that audiences should not expect to be entertained by the film, but that some effort would be required to understand it.35

Scientists and Academics

Laymen were not the only people who were skeptical that Einstein’s theory of relativity could be made accessible through the medium of film. Scientists and academics also felt that the limit to public understanding of science had been exceeded by Einstein’s theory.

Dr. Albert Neuburger posed a basic question in the B.Z. [Berliner Zeitung] am Mittag:

Is it possible to film a theory? If this is somewhat doubtful with views supported by effective experiments, the doubt will increase when the theory represents a product of purely deductive thinking based on mathematical principles, as is the case for Einstein’s theory of relativity.36

Max von Laue (1879–1960), in commenting on the “Einstein film” in Die Naturwissenschaften, emphasized that he welcomed educational films that explain complex scientific questions, but that the Einstein film failed to do so, because it was too comprehensive for laymen and not comprehensive enough for scientists, so it appealed to neither group. Furthermore, he pointed out several substantial mistakes in the film, for example, that the clocks on the moving train and those on the bridge that the train is crossing showed the same time when they coincided, while according to the Lorentz time transformation they have to differ.37

Dr. R. Volz made a different point in his critique:

The scientific portrayal of Einstein’s theory is a mathematical one, and mathematics functions precisely enough to make a film appear unnecessary. Therefore scientists cannot gain anything new from a film. … This is strictly a matter of science and should not be used in a film to be laid open to new improper judgments.38

Volz thus objected to Kornblum’s film because Einstein’s theory of relativity is too difficult for laymen to understand, and hence there were dangers in popularizing it. He was alluding here to the denunciation of relativity as a “relativistic” or even “Jewish” theory. Thus, the issue here was not an incorrectly understood physical theory, but rather was inherently political.

Politically Motivated Opponents

In 1922, when the Einstein film appeared, the political climate in Germany was heated. As noted above, the revolutionary Einstein (figure 6) had already faced public resentment when a public lecture series organized by the antirelativistic agitator Paul Weyland (1888–1972) took place in the large auditorium of the Berlin Philharmonic in August 1920. Politically motivated attacks on Einstein—democrat, internationalist, Jew—though they did not account for the majority of objections to his theory of relativity,39 gained great strength in 1922 when the German foreign minister Walther Rathenau (1867–1922) was assassinated by right-wing extremists and rumors spread that Einstein also was on their list.40 Against this background, Kornblum’s film was drawn into harsh political polemics.

Fig. 6
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Albert Einstein (1879–1955) shown with the most popular illustrations of his special and general theories of relativity, a rapidly moving and contracting train and the deflection of starlight during a solar eclipse. Source: Serviss, Einstein Theory (ref. 2), frontispiece

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A review that appeared in the film journal Kino-Rat under the headline, “The Film of Physical Nihilism,” constituted a personal attack on Einstein:

Einstein creates a universe using the imperfection of our sensory perception. He preaches to us: All of your perceptions are relative, therefore you must construct a relative universe following my formula. This is nothing but the most unproductive scientific nihilism and is in accordance with the political past of the professor, who belongs to political parties that intend to relativize the national sense of honor. … All Einsteinians with their comprehension-simulating Bolshevik-Zionist clique cannot deny the fact that time, space, and matter exist infinitely, and that, from a given center, one can indeed develop an absolute worldview.41

In the Casseler Allgemeine Zeitung, Kornblum’s film was tied to ethical relativism, the reviewer claiming that “this theory [of relativity] is dangerous in its logical conclusions for ethics, for if there is nothing absolute, then the assessment of human toil is also questionable,” and is tied to political propaganda:

It is surely in the character of the times that such ideas are propagated and echoed, … even more so when, as implied, they are supported by clever publicity that is pursued with great expenditure. The Einstein film is part of this publicity, which uses all the illusions of trick shots in order to cram this “wonder of the world” into one’s head.42

The reference here to “publicity” or propaganda as an explanation for Einstein’s success was common among opponents of his theory of relativity. It was spread, in particular, by Ernst Gehrcke, who as early as 1912 referred to Einstein’s theory of relativity as a “mass suggestion,”43 and who later developed the argument that this “mass suggestion” was triggered and spread by “publicity” in the daily press.44 Nourished by the social, economic, political, and cultural upheavals after the Great War and by Germany’s perceived cultural degeneration, Gehrcke argued that “mass suggestion” accounted for both the favorable publicity accorded to Einstein’s theory of relativity, and for the lack of success of its opponents.45

Conclusion

To return to the question posed at the outset about why an educational film—the Einstein film—became a box-office hit and the subject of public controversy, I have shown that the range of comments on Einstein’s theory of relativity generated by its screening reached far beyond that of other scientific educational films. The diverse cross section of opinions presented shows that public response in Germany to the Einstein film has to be placed within the context of the much broader public debate on Einstein’s theory of relativity, which ranged from enthusiasm for it by Einstein’s friends and supporters to opposition to it by nationalists and anti-Semites. These two extremes peaked in 1922. While the impact of Kornblum’s film was great owing to the intense public debate at the time about Einstein and his theory of relativity, opponents and polemicists exploited this debate by using it as a pretext to attack Einstein politically. It was against this background that some scientists objected to the presentation of theoretical physics in this popular form. This was also at the root of Einstein’s own reaction, in particular, the way in which he distanced himself from the film, and agreed only privately with Kornblum that he would read the screenplay—on the condition that this would not be made public.