Figure 12.1 Max Planck delivers a talk in Stuttgart on June 24, 1935.
Erwin’s employer received a brief letter from the office of Heinrich Himmler, Reichsführer of the SS. The Otto Wolff Company had lobbied on Erwin’s behalf, describing his importance not just to their operations, but also to international relations and the success of the Reich. They described him as the key person for their confidential international business (primarily obtaining metals for war machinery). But the reply from Himmler’s office didn’t stop at refusing their request. It cautioned them that further pursuit of Erwin’s case, “would mean an undesirable burden” for the company. Shortly thereafter, the firm requested that Erwin resign his position, and he complied from his jail cell. This left Nelly with no income and an actual debt, as his former employer claimed they’d overpaid Erwin in royalties.1
Max Planck decided to travel to Berlin, despite the condition of the city, to join forces with Nelly—or Nellchen, little Nelly, as he called her now. In a letter to Max von Laue, he said he had trouble wrapping his head around the case. Erwin must have been arrested just because he knew some of the would-be assassins—that’s all. And Planck said he took comfort in the fact that so many people were arrested, including some just as prominent as Erwin.2
Max and Nelly decided to triangulate on Heinrich Himmler in part because of family connections. Nelly’s sister knew Himmler’s wife and wrote two letters beseeching Frau Himmler’s influence with her husband. Meanwhile, Max wrote to Herr Himmler directly.
I was informed by my daughter in law that my son Erwin was arrested 23 July and that his situation is said to be very serious. Because of the deep relationship with my son, I am convinced that he had nothing to do with the events of 20 July. I am 87 years old and am relying in every regard on the help of my son. Until today, I have strived to live my science and my honorary positions and, in this way, to serve my Fatherland. I was only able to do this because of my son’s assistance in all affairs. At the end of my life, this son is the only one remaining from my first marriage.
To underline Erwin’s importance, he makes a distasteful addition, hopefully without Marga’s knowledge.
My son from my second marriage is not intellectually fit to carry on the family standards, while Erwin’s character and his gifts embody everything from generations of our family. I am asking you, honorable Herr Reichsführer, to put yourself in my situation and try to understand what it would mean to me, while also considering the prestige of my name in Germany and abroad, if I had to lose my son due to a harsh sentence.3
By mid-September, they had their answers. A letter from Himmler’s staff informed Max that the charges and evidence against Erwin were so strong “that a release is impossible.” Meanwhile, the Reich still denied Max and Nelly’s petition to visit him. Their only small comfort came in the form of Erwin’s short letters from prison, sending his love, saying he was fine, thanking them for the good thoughts, but not saying much about his imprisonment. He requested a few items that would make his stay more bearable, like a copy of Homer’s Odyssey.4
In truth, Max had no good options for sympathy in the Reich. Despite pledging his support for the Nazis in 1933, he never joined the party, and over the next decade, he suffered increasing scrutiny and criticism from Reich stalwarts.
His summer 1933 report for the Kaiser Wilhelm Society (KWG) shows him playing by the new rules. The Reich requested he dismiss twenty-seven Jewish assistants of the society. His reply broke these into three groups: nineteen he dismissed (yes, as you wish); three questionable cases (maybe, but this is complicated); and five “cases of hardship” (best if we keep them, for the good of the society). But by the end of July, Planck told several directors he had failed to obtain some of the exemptions.5 Records show him continuing to campaign for certain people, predominantly those staff within the family trees of well-known scientists. He tried to obtain official exceptions to the new laws or even Aryanize individuals like Mathilde Hertz, a relative of the great Heinrich Hertz. His efforts for Mathilde lasted two progress-free years, and she left for England in 1935.6
Meanwhile, Planck continued to pitch the Nazi nastiness as transient, like some physical effect that would fall exponentially with time—“a thunderstorm which would soon pass away,” he liked to say.7 One Jewish scientist heeding his advice was the biochemist Carl Neuberg. While chemist Walther Nernst advised Neuberg and others to leave in 1933, many followed Planck’s advice instead. “He said I was protected as an old civil servant of the Kaiserreich,” Neuberg wrote. “Later I was forbidden to leave the country.”8 Neuberg eventually escaped, and though he survived the Nazi era, he looked back on Planck’s advice with bitterness.
In the following year, Planck began to push back using a narrative of pragmatism. He noted that extreme acts and policies within Germany would hurt the Fatherland’s international reputation. He particularly spoke out against any government funding for eugenics and related pseudoscience that would reinforce growing disdain and disbelief in other international quarters. Such reactions abroad had real consequences for Planck. He’d been working with the Rockefeller Foundation to finally design and build the Kaiser Wilhelm Institute of Physics. The Institute’s meeting minutes of the time underline his worries: “Privy Councilor Planck and the undersigned stated that it was necessary that … nothing happen in German science that might disturb the Americans, because undoubtedly a certain reticence can be felt at this time.”9 In the same meeting, Planck emphasized the emerging importance of atomic research, following the revelations of Hahn, Meitner (in exile), and others.
We glimpse a biased but telling view of Planck in 1934 from the diary of Lotte Warburg, daughter of the deceased physicist Emil Warburg. “Why does he stay on and allow himself to discharge people from the KWG? … Why does he go about hunched over, moaning and complaining, instead of throwing back his head and damning them all?”10
He wasn’t shouting down the Reich, but he wasn’t curling into a ball either. In January of that year, he organized a memorial against government orders. The Jewish chemist Fritz Haber had died in exile, and although the Nazis forbade any civil servant from recognizing Haber, Planck gathered von Laue, Otto Hahn, Lise Meitner, and several others to pay their respects. “Haber kept faith with us,” Planck said. “We shall keep faith with him.”11 Later that year, Planck again refused to supplicate. When President von Hindenburg died in August, Hitler quickly moved to merge the roles of the president and chancellor, cementing a dictatorship. Johannes Stark drafted a proclamation of support, but Planck and von Laue refused to sign.12
In 1935, Max continued to sharpen his arguments about the utility of science for the Reich. His new KWG reports began emphasizing the role that science could play in international relations, removing rough edges and negative impressions. “Many a misleading view abroad can be rectified,” he suggested.13
At the same time, he clearly realized that negative views were not misleading at all. In 1935, physicist James Franck invited Planck to Denmark. “No, I cannot travel abroad,” he replied. “On my previous travels I felt myself to be a representative of German science and was proud of it. Now I would have to hide my face in shame.”14 He launched a new public lecture, “Physics and the Struggle for a World View.” Lise Meitner later remembered this one with admiration, as he underlined that “justness is inseparable from devotion to the truth.” Planck linked the enterprise of science to the underpinnings of a healthy society. He warned audiences against becoming a community in which, “the guarantee of justice begins to vacillate,” and against a system in which rank or heritage affect legal protections—this was not a subtle jab.15
And so from the earliest time of the Nazis, we see a consistent approach from Max Planck (Figure 12.1). While he would never openly challenge the government, he never fully aligned either; he continued to make statements between the lines and to defy them in quiet ways. He saluted the Nazi flag and signed official letters “Heil Hitler!” but he also preached international cooperation and pursued amnesty for his Jewish colleagues.
Figure 12.1 Max Planck delivers a talk in Stuttgart on June 24, 1935.
In early 1936, he feared losing his balance on this razor’s edge when the American press threw a spotlight on his sentiments. In an article titled “The Last Stand,” the New York Times reviewed one of his public speeches and painted him as a bold intellectual, standing against the Reich from within. “Max Planck, to his everlasting glory, went as far as common sense permitted.” They translated his public message to be that, “personalities and brains count for more than race or totalitarianism.” Planck was horrified, fearing what a backlash might mean for his Jewish colleagues at the KWG.16
One way or another, the Reich noticed Planck as a public persona resisting their Gleichschaltung movement. The word literally means “equal switching,” and was used by the Nazis to suggest the mass alignment of all German citizens to the same goals, swearing allegiance to their country and party (increasingly synonymous). In March 1936, for instance, two enormous new zeppelins, the Graf and the Hindenburg, loomed roaring over the country dropping leaflets with voting instructions. The upcoming referendum would place Nazis throughout the Reichstag and support Hitler’s alarming international bravado. Any opposition had to be silenced, even minor irritants like Planck.
Ernst Gehrcke, the physicist who had joined Weyland’s anti-Einstein stage show in 1920, emerged now to revisit Planck’s famous discovery. He published an April 1936 article entitled “How the Energy Distribution of Black-Body Radiation Was Really Found,” in Physikalische Zeitschrift. Much more dangerous and credentialed than the Weylands of the world, Gehrcke made for an insidious adversary. He wrote a detailed alternate history in which the experimenters of 1900 had actually mapped the perfect formula and then shared it with Planck. “It is characteristic of the physics of the past epoch that Planck’s elementary mathematical trimmings were esteemed more highly than the original, fundamental physics discovery by Lummer and Pringsheim.”17 For Nazi sympathizers, that epoch meant the deluded “Jewish Physics” dark ages. According to Gehrcke, Planck was only famous because he had supported the public relations machine of Jewish scientists. Meanwhile, Stark began to repeatedly attack Planck in public, calling him a “nefarious influence,” and one of Einstein’s “creatures.” Planck, “showed himself to be so ignorant about race that he took Einstein to be a real German who should be honored in his country.” Lenard joined the chorus, calling the entire KWG a “Jewish monstrosity.” With Planck as president, Lenard said the society should be disbanded.18
The Reich spoke an increasingly negative line against science. In the fall of 1936, Hitler instituted a new law forbidding any German from accepting a Nobel Prize. The value of such awards had plummeted in the Führer’s eyes when the German pacifist and concentration camp prisoner Carl von Ossietzky won the Nobel Peace Prize that year.19
Planck clung to his post, hoping to still do some internal good, and the attacks continued. In 1937, the SS newspaper Das Schwarze Korps labeled Planck a “white Jew” for following in the footsteps of Einstein. And now he would be investigated for rumors of Jewish heritage—the charges moved from Max being a “white Jew” to, perhaps, a one-sixteenth actual Jew.20
Meanwhile, the drumbeat of war grew louder. Agricultural lands were repurposed to the military, and food rationing began. Max von Laue surveyed the landscape of his homeland and found a way to send his only son to America.21 (Theodore von Laue would go on to earn a PhD in history at Princeton and make pointed criticism of his father and other German scientists after the war.)22
Just a year from the outbreak of World War II, Planck presented the 1938 Planck medal to the young French physicist Louis de Broglie, a double insult to Nazis, as he was not only French but also following the ways of “Jewish Physics.” With a presentation to the French ambassador, Planck said, “May a kind fate grant that France and Germany come together before it is too late for Europe.” The ambassador replied with words that echo in Planck’s long legacy. “In Herr Geheimrat Planck we honor one of those accomplished men of whom not only his country but the entire world has a right to be proud.”23
Planck, now 79, decided to resign as president of the KWS, but he maintained his post as secretary of the Prussian Academy of Sciences. (Others of the old guard who had never joined the party also stepped down. His neighbor Karl Bonhöffer, for instance, retired from the Department of Psychiatry and Neurology. An SS officer took over and started euthanizing psychiatric patients.) That fall, the University of Berlin banned Jewish students from attending the regular physics colloquia, and Planck was asked to dismiss three Jewish colleagues from the Academy. He did as he was asked and wrote to von Laue his relief that the three, like the Jewish students, hadn’t made a spectacle of the awkward situation.24 By the end of 1938, Meitner had fled, the Nazis owned the Academy, and Max had resigned his last official position. At 80, he was finally and completely retired, having set each of his many official hats aside.
His eightieth birthday provided a bright spot of levity. His friends and colleagues came together for a “great celebration of the physicists” hosted at Berlin’s Harnack House on April 23. The party featured a one-act farce about the history of quantum theory. Physicists including Peter Debye, Arnold Sommerfeld, and Werner Heisenberg prowled the stage.25 Also delighting Planck that year was the opening of the new physical home of the Kaiser Wilhelm Institute for Physics. Its large, windowless tower housed new particle physics experiments. Electrified to one million volts, instruments running the length of the tower could observe the creation of electron-positron pairs.26 Institute director Peter Debye christened this the Planck tower, and today, it houses archives of the Max Planck Society (formerly the KWG) in southwest Berlin.
But the world outside the temples and towers of science was less appreciative of Planck. Despite his stepping away from work and spending more time with Marga, Nelly and Erwin in the mountains, the public attacks against Planck continued, but now more from the likes of the Reich Student Command, a Nazi youth organization. Their newspaper labeled Planck “founder and ringleader” of the nation’s wrongful turn to mathematical physics, “which rules out any real thinking.”27
Planck saw the march to another war as a “sadly grave” time for his Fatherland. “I, for one, see in current developments basically only a senseless self-decapitation of the Aryan-Germanic race,” he wrote to a colleague in 1940. “Only the gods know how this will end.”28
From our great remove, one can certainly ask why Planck stayed or, having decided to stay, why he failed to do more given the evidence around him. Why would he even agree to lecture in occupied territories, no matter the content, where in plain sight German forces exerted such a cruel and obvious grip? A typical reply would underline his pragmatism and his age. He was nearing the end of his career and the end of his life, thinking he could do more good quietly inside than he could do loudly outside. (As Carl von Ossietzky allegedly said when opting to stay in Nazi Germany, it is a hollow voice that speaks from across the border.)29 But setting age and pragmatism aside, two stories leaven an emerging picture.
In 1907, when Max Planck swam in familial happiness and the giddy early days of Einstein’s relativity, he sat with an enticing job offer. After Ludwig Boltzmann’s suicide, Planck interviewed in Vienna as a possible replacement, and it was during this visit that the young Lise Meitner heard him give a lecture. His interview went well enough that the University of Vienna extended an offer, and he faced a difficult decision. At age 49, had he accomplished all he could in Berlin? Wouldn’t it be wonderful to be closer to the beloved Alps? And immersed in Vienna’s music? Would a move benefit or harm Marie’s fragile health? And what were they going to do with their increasingly empty Grunewald nest anyway?
But Planck opted to stay. He identified too strongly with the empire that had grown with him to maturity, success, and esteem. And all signs suggested the best was yet to come. If he won the Nobel Prize, as many suggested, shouldn’t he receive that in Berlin? The news of his decision spread quickly in Berlin, and in the middle of a dark Grunewald night, Marie and Max woke to singing outside their home. When Max went blinking to the door, he heard a song from his youth, a sailing song of Kielers, coming full throat from a mob of torch-bearing students. Beer breath, spittle, and testosterone must have hit Max Planck in gusts. The students came to show their love for their professor and cheer the good news. And when they finished their song, he confirmed he was staying. He shouted into that feral night that he would never leave.30
The second story illuminating Planck’s Nazi-era behavior doesn’t involve him at all. The Swedish journalist Gunnar Pihl relays a common story from the middle and late 1930s. It exemplifies the kind of tale Germans traded in hushed tones during the years of the Third Reich, and certainly, Max Planck had heard it or stories much like it. As Hitler consolidated power and held sham votes along the way, one Catholic clergyman told his congregation, “I, Bishop of Münster, have voted against Hitler.” He said he must stand against obvious evil, and he was arrested later that day while the pews were still warm. But the town of Münster was the boyhood home to German hero and flying ace Colonel Werner Mölders. When Mölders heard of his bishop’s arrest, he gathered his party membership card with all his war medals and mailed them to a Nazi party office. Facing a rebuke from the popular hero, the Nazis quickly released the bishop and returned the materials to Colonel Mölders. So a prominent figure could and did stand up to the Nazis. And within a few weeks, the colonel was dead, allegedly killed in a routine solo flight. But those near the airfield reported no wreck, only the horrific sight of a body falling to earth, pushed from a plane far overhead.31
Planck was caught between an incredible allegiance to and identification with Germany, on the one hand, and the practical reality of what could be accomplished in protest, on the other. This neither excuses his actions nor completes a measure of his conscience, but by carefully mapping his boundaries, we take another step toward understanding what he did and didn’t do.
Planck had little direct contact with the Reich’s machinery from the time of his resignations until the time of Erwin’s arrest, roughly six years later. He threw himself into his philosophical lectures, his correspondence, and the remnants of his family, including Erwin, Nelly, and granddaughters Grete Marie and Emmerle. In 1944, he was ill equipped to gauge, let alone affect, the internal dynamics of the Third Reich.
Perhaps he and Nelly focused their efforts on the family of Himmler because they had heard of other cases where familial sentimentality thawed his ruthless Nazi gaze. Heisenberg, for instance, found himself under public attack in 1937—he was yet another deluded Einstein worshiper according to Stark and the SS. Heisenberg’s mother wrote a note to Himmler’s mother, as if the entire episode had been a misunderstanding on a childhood swing set, and the letter worked magic. Himmler wrote to Heisenberg directly, admitting, “You were recommended by my family.” He assured the physicist, “I have put a stop to any further attack on you.”32 Heisenberg’s reputation was not assailed further (at least in Germany), and he would go on to lead the German uranium project.
But Nelly and Max had no success via Himmler’s wife. The Planck clan tried to maintain one another’s spirits—Nelly sugar-coated things for Max where she could, and, as in the following letter, he in turn chided her for working too hard for the war effort, including running an early version of an X-ray machine for the wounded.
I knew from the beginning that your work is exhausting and also dangerous because of the radiation. But I think it is irresponsible that you additionally put your health at risk with your constant blood donations. You are usually so smart and prepared for all eventualities, but in this case you are like a child who cannot consider the future. What do you gain from all your sacrifice, when Mops will return to find, not his normal chubby wife, but a skeleton, somehow alive but without her normal charms? … please, dearest little Nelly, take this advice to your heart from your father who is worried about both of you to the same extent, and look forward to the moment you embrace your Mops again.33
Even as Planck made requests of the Reich, he made little effort to endear himself to the Nazis. He missed a mid-October deadline to submit a requested propaganda testimonial, one for the “Confession to the Führer” series. He finally just wrote, “I am sorry to tell you that because of the imprisonment of my son, I am unable to find the words that would be consistent with the purpose of this brochure.”34
On October 23, 1944, Erwin went to trial, or what passed as such. His official charges declared:
• Preparing high treason,
• To alter the Reich with violence,
• To attempt to remove the constitutionally provided powers of the Führer,
• To establish a group preparing high treason, and
• Abetting hostile forces during a time of war.35
The “People’s Court” hosted the case. Defendants here were often made to wear court-provided clothing: a shabby jacket, no tie, and for some, oversized pants with no belt. Judicial president Roland Freisler ruled here, shouting down defendants, asking rhetorical and humiliating questions. The word “shouting” cannot convey the absurd violence of Freisler’s voice. The court in action is readily and sickeningly available for viewing today, as the sessions were recorded both for propaganda and Hitler’s viewing pleasure.
If Erwin looked about the grim room, he saw only party officials and a few Nazi propaganda “journalists.” Family and friends of any sort were forbidden from the chambers. In the brief “trial,” Erwin and his lawyer built a narrative of Erwin always trying to be a good German. He had told the conspirators he just wanted to avoid the horror of 1918. He worried about what would happen when the Allies overran them. When others approached him discussing a diplomatic path to peace, he refused them, but he thought it his patriotic duty to listen.36 Such an argument won no sympathy from Freisler, who pronounced Erwin’s death sentence and moved to the next case.
Two days after the verdict, Max Planck sent a letter directly to Hitler.
I am deeply shaken by the news that my son Erwin was sentenced to death by the People’s Court.
As you’ve repeatedly commended me—in the most honorable expression of recognition—for my achievements in the service of our Fatherland, I feel entitled to ask that you lend a sympathetic ear to an 87-year-old.
As thanks from the German people for my life’s work—which has become an everlasting intellectual asset for Germany—I ask for my son’s life.37
If Planck received any response, it has not survived. As von Laue wrote to Lise Meitner in Stockholm, “one has not much hope.”38
Planck also wrote directly to Himmler once more. He attached his earlier letter and now pleaded for the commuting of Erwin’s sentence to life in prison. Erwin’s company risked irking the Reich and wrote a series of new letters on Erwin’s behalf. Nelly, along with her friends and family wrote to an array of Nazi officials, including Franz von Papen, the former Weimar-era chancellor who had somehow appeased his new overlords. In this case Nelly’s letter, co-signed by Max Planck, received a personal reply.
Madam!
I received your letter today and was very shocked by the news of your husband’s sentence. I was convinced that he completely withdrew from all political activity after that business in 1934. Due to the direct orders of the Führer, I am absolutely prohibited from filing or supporting clemency pleas—so I regret that there is no way I can assist. But even though I am completely ignorant about this case, I might hope—due to the great standing of your father in law—that the Führer might grant your clemency plea. I hope you will be spared the most difficult outcome.39