Getty / Arsh Raziuddin / The Atlantic

Jacques Monod arrived in Paris to some dreadful news. On June 5, 1944, four years into the German occupation of France during World War II, he was supposed to meet with fellow leaders in the French Resistance when his assistant, Geneviève Noufflard, told him that several commanders within the greater Paris region had just been caught by the Gestapo.

Monod was pretty sure that at least one of those arrested knew about the rendezvous he was planning to have that day. Since no one could predict who might buckle under the Gestapo’s pressure and give away names and addresses, he was immediately at risk.

An officer in the bureau that directed ambushes and sabotage against the German forces, Monod had made sure to take many precautions to avoid getting caught. A few months earlier, after his superior in the Resistance had been lured into a trap and captured, Monod had gone completely underground. The 34-year-old biologist abandoned his laboratory research at the Sorbonne, moved his Jewish wife and young sons to the suburbs, adopted a new alias, changed his hair color and clothing style, started wearing tinted glasses, and rotated between different safe houses.

Monod may have gone into hiding, but the meeting that day was crucial. Four nights earlier, the BBC had aired a string of coded messages in French, including “Ma femme a l’oeil vif” (“My wife has a lively expression”), the specific phrase that Monod and Paris commanders had been waiting for that signaled an Allied invasion was imminent.

Taking care to make sure that they weren’t being followed, Monod and Noufflard bicycled to the scheduled meeting six miles south of Paris. As Monod approached the hideout, he was wracked with the same question that had preceded similar clandestine meetings: Should he continue on and walk into the building, and risk never seeing his wife and children again, or just turn around and go back home?

He went inside the house. Other officers soon arrived, and the meeting went off without a hitch. That evening, the BBC broadcasted another stream of messages, including four phrases signaling to the Paris branch of the Resistance that they were to execute their sabotage plans: The invasion was on.

Monod was a man who took chances. He was one of the few early joiners of the Resistance, narrowly escaping arrest in 1940. Three years later, he made two secret trips to Switzerland to solicit arms and other supplies from the Allies. Once the invasion was under way, he crisscrossed boulevards and barricades under fire to help coordinate the uprising that liberated Paris.

But he was also someone who understood chance better than anyone in his day. He was not a mathematician or a bookie, but a biologist, and an extraordinary one at that: A pioneering molecular biologist, he would go on to win a Nobel Prize. Monod spent his life studying what he dubbed “the secrets of life”—the mysterious workings of genes that determine the properties of living things. And at the center of those secrets was the role of chance. He would deploy the idea beyond the realm of science, using it to powerful political and philosophical ends.

Monod was keen to hurl himself back into research after the war, but that hope didn’t last very long. He was once again compelled into action, but this time, the threat wasn’t an invading army but simply an esoteric scientific matter—or at least it seemed that way at first. As Monod discovered, the dispute was really a clash between two competing Cold War ideologies. And this world-shaping conflict hinged entirely on the idea of chance.

In August 1948, Monod read in one of the leading French Communist newspapers about a great debate between Soviet biologists that had just taken place at a meeting of the Lenin Academy of Agricultural Sciences, which oversaw the USSR’s crop breeding. On one side were biologists who subscribed to the principles of heredity discovered by the scientists Gregor Mendel and Thomas Hunt Morgan, namely the idea that organisms carry two alternative versions of each trait in their chromosomes, which are inherited at random by their offspring. On the other side were adherents of the Soviet botanist Trofim Lysenko, who denied these principles.

Monod’s ID card from his time in the French Resistance. The name “Malivert” is an alias. (Courtesy of Olivier Monod)

For Monod, who had spent a year working in Morgan’s lab at Caltech, the news from Moscow was shocking and puzzling. The USSR had once been home to many respected geneticists. What would cause them to reject a half century of science, Monod wondered? And just who was this Lysenko?

The stakes of the debate were both practical and political. Crop yields were a major challenge for the USSR after the Russian Revolution. Traditional breeders had modified crops and livestock over many generations by selectively breeding slight variants that arise within populations of plants and animals. But Lysenko and his followers claimed that there was a faster way of improving crops. They suggested that large changes in plants could be induced in response to external environmental conditions, and that these characteristics could be passed on immediately to their offspring.

Lysenko was largely unknown outside the Soviet Union, but he was exalted and very powerful within the country. A Ukrainian peasant’s son with only a meager education, he had risen to national fame through his work as an assistant at an agricultural station in Azerbaijan. Lysenko tested the idea that plants such as peas could be grown in the winter, providing fodder for livestock and nourishing the soil for cotton planted in the spring. The first year brought a mild winter and promising success. A journalist for Pravda, then the official paper of the Communist Party, sensationalized the results and portrayed Lysenko as a Soviet hero. Although the experiment was not successfully repeated and winter pea crops later failed, Lysenko learned a valuable lesson in propaganda.

He then turned his attention to a technique called vernalization, a means of priming crops for the spring by soaking seeds in cool water. He even boasted of transforming wheat into rye. Lysenko and his followers denied the existence of chromosomes and claimed that “human intervention makes it possible to coerce each animal or plant form to be modified more rapidly and in whatever way desirable to man.” The implication that plants, animals, and, by extension, people, could be shaped in any desirable way, unconstrained by heredity, fit with Marxist theory. Traditional genetics was therefore an obstacle to the Soviet struggle—“reactionary,” “bourgeois,” and “erroneous,” as Lysenko described it—and to be banned. It was just what the Communist Party leaders wanted to hear. Lysenko was awarded the country’s highest honors and made president of the Lenin Academy of Agricultural Sciences.

But for more than a decade, Lysenko had encountered a great deal of skepticism from other Russian scientists about the positive results he reported, which were often based on small sample sizes, frequently used inaccurate or falsified data, and usually lacked experimental controls. In the face of repeated crop failures, he was criticized for his rejection of traditional breeding methods used in the West. At the August 1948 meeting, Lysenko sought to silence his critics once and for all, or to purge them from the Russian academy. With Stalin’s full backing, he prevailed.

The Lysenkoist line coming from Moscow posed a painful dilemma for the many French scientists who were members of the very large and popular French Communist Party: Should they adhere to their political allegiances and toe the party line? Or, instead, should they defend genetics and break from the party? For an entire week in September 1948, the major newspaper Combat provided a forum for French scientists to debate it, under the headline “Mendel … or Lysenko.” The biologist Marcel Prenant, Monod’s former chief in the Resistance, sought to reconcile the two camps. He asserted that Lysenko did not reject the existence of genes and chromosomes, and had achieved important results.

Monod’s turn came the following day, and he was having none of Prenant’s apologetics. He charged his former comrade with embarrassing himself with contradictory explanations. No, Monod alleged, “the system by which [Lysenko] proposes to replace genetics is a muddle of propositions which are mutually contradictory when they are not meaningless.”

But he also articulated what he viewed as the greater threat: the Soviet Union itself. “What begs to be understood is how Lysenko was able to obtain sufficient power and influence to subjugate his colleagues,” he wrote, “to win the support of the radio and the press, the approval of the Central Committee and of Stalin personally, to the extent that today Lysenko’s derisory ‘Truth’ is the official truth guaranteed by the state, that everything that deviates from it is ‘irrevocably outlawed’ from Soviet science.”

The power of the USSR was such, Monod explained, “that his opponents who defend science, progress, and the interest of the nation against him are expelled, pilloried as ‘slaves of bourgeois science,’ and practically accused of treason. All of this is senseless, monstrous, unbelievable. Yet it is true. What has happened?”

Trofim Lysenko not only denied a half-century of science; he sought to purge the Soviet Union of biologists who disagreed with him. (Getty)

It was a bold, devastating attack. Monod had many colleagues and even family members who belonged to the Communist Party. His essay was far more than a critique of some specialist branch of Soviet biology, it was a condemnation of the entire Soviet way of thinking. The more he looked into his own question about what had happened to Soviet science, the more he discovered that most of Lysenko’s key objections to genetics pivoted on, of all things, a misunderstanding of chance.

For decades, scientists had observed that mutations in genes arose spontaneously at a low, but measurable, rate. They could not predict whether any given individual plant, animal, or bacterium would bear a particular new mutation; it was a matter of probability, of random chance. Since no one could predict which chromosomes would be inherited by an individual animal or plant, geneticists understood fertilization to be a random process.

But to Lysenko, this unpredictability meant that genetics was a false science. “Mendelism-Morganism is built entirely on chance; this ‘science’ therefore … condemns practical workers to fruitless waiting,” he told the academy. “By ridding our science of Mendelism-Morganism, we will expel fortuities from biological science. We must firmly remember that science is the enemy of chance.” Lysenko added that “physics and chemistry have been rid of fortuities. That is why they have become exact sciences.”

With that statement, Monod realized that Lysenko had revealed the even greater depths of his ignorance. Physicists and chemists had shown that the behavior of molecules, atoms, and subatomic particles were statistical in nature. Nearly all of their laws expressed probabilities. To take Lysenko at his word, Monod wrote, “it would be necessary to renounce not only genetics, but modern physics, radioactivity and quantum theory, the gas Laws, chemical kinetics, thermodynamics.”

Monod was not the only Frenchman alarmed by developments in the Soviet Union. At the time, the writer Albert Camus was working on The Rebel, a book that would estrange him instantly and permanently from the Communist left in France. Monod was introduced to Camus, and they became fast friends. Thanks to Monod, Camus inserted a sophisticated scientific critique into his clear-eyed, damning indictment of Communism that did a great deal to derail Soviet influence in France and the West.

Nevertheless, Lysenko retained his stranglehold on Soviet biology for another 15 years, even steadfastly refusing to accept the discovery of DNA as the basis of heredity. All the while, his agricultural programs were disasters that perpetuated chronic food shortages. But today, Lysenko has become the quintessential model of scientific denialism. For Monod, the USSR’s move to take Lysenko at his word, to triumph ideology over science, was “a purely theological affair.” It was also a formative prelude to a broader philosophical view of chance and a broadside against all theologies.

For 20 years following the Lysenko episode, Monod was at the forefront of the revolution in molecular biology that deciphered the structure of DNA and cracked the genetic code. He shared a Nobel Prize with two close collaborators for fundamental discoveries about how gene activity is regulated. With all of this new knowledge, Monod saw an opportunity to return to the matter of chance with much greater force than during his exposé of Lysenko.

Steeped in France’s deep philosophical traditions, Monod was interested in science for more than just science’s sake. He felt that the public misunderstood the purpose of science as enabling the creation of technology, but he believed that technology was merely a by-product of it. “The most important results of science have been to change the relationship of man to the universe,” he once said, “or the way he sees himself in the universe.”

In the twilight of his career, he sought to spread that message by writing a book that would explain the meaning of modern biology to laypeople. Nothing about the start of the book is exceptional. Monod used several chapters to describe the insights that had very recently emerged from the study of DNA and the deciphering of the genetic code. He understood that this knowledge would be unfamiliar to most readers, so he included an appendix with chemical structures of proteins and nucleic acids, and a primer on how the genetic code worked. In a dry, matter-of-fact style, he explained how genetic mutations were now understood to be accidental alterations—substitutions, additions, deletions, or rearrangements—in the sequence of DNA, in the order of the long strings of bases that make up genes.

But then, almost without warning, he turned to the broader implications of how mutations arise in DNA, delivering a stunningly powerful idea. “We call these events accidental; we say they are random occurrences,” he wrote. “And since they constitute the only possible source of modifications in the genetic text, itself the sole repository of the organism’s hereditary structure, it necessarily follows that chance alone is at the source of every innovation, of all creation in the biosphere … There is no scientific concept, in any of the sciences, more destructive of anthropocentrism than this one.”

In essence, what had once been obscure discoveries in biochemistry and genetics had not only advanced our understanding of life, they also had overturned millennia of religion and philosophy that had placed humans at the apex of creation. “Man was the product of an incalculable number of fortuitous events,” Monod wrote. “The result of a huge Monte Carlo game, where our number eventually did come out, when it might not well have appeared.”

A first-time author, Monod did not know what to expect when the book, Chance and Necessity, was first published in October 1970, exactly 50 years ago. La merde hit the fan.

The book rocketed up to number two on France’s best-seller list, and Monod gave scores of interviews that brought it even more attention. Immediately, many commentators recognized the threat that chance posed to traditional Western ideas of humanity’s origins and purpose. Arthur Peacocke, a British biochemist turned prominent theologian, suggested that Monod had put forth “one of the strongest and most influential attacks of the century on theism.”

A flurry of counterattacks appeared, with titles such as Anti-Chance, and Beyond Chance & Necessity. The theologian R. C. Sproul sounded echoes of Lysenko in his book Not a Chance, when he wrote, “Chance as a real force is a myth. It has no basis in reality and no place in scientific inquiry. For science and philosophy to continue the advance in knowledge, chance must be demythologized once and for all.”

Monod gladly took on challengers in debates on television and radio, and in print. What Sproul and other theologians argued, or perhaps at least hoped, was that what scientists perceived as chance merely reflected a lack of knowledge of the true causes of events, that is, God’s intervention or some other undiscovered natural law ordained by God. Like the Soviets before them, they were unable and unwilling to budge from their dogmatic stance against chance, regardless of the evidence.

If Monod were alive today, even he would not be able to imagine all the realms in which chance has revealed itself. Fifty years later, chance only plays a bigger role in what we know about nature and our origins.

As scientists have learned much more about the history and workings of the planet, they have been startled to discover how the course of life has been buffeted by a variety of cosmological and geological accidents—without which we would not be here. The most surprising and famous is the discovery in 1980 that life’s history was rewritten in an instant by a very rare, large asteroid strike 66 million years ago. That impact triggered the demise of the great dinosaurs and three-quarters of all animal and plant species on the planet, but it also cleared the way for the rise of mammals, our primate ancestors, and, eventually … us.

At the opposite end of the scale, at the atomic level, biochemists have caught chance red-handed. They have captured the fleeting moment when a subtle shape-shift within DNA causes a mutation, the change that is at the very root of all the diversity and beauty in living things, as well as of pandemics and cancer. This spectacular accomplishment reveals how mutation is a built-in feature, not a bug, in DNA, an unavoidable, inevitable consequence of DNA chemistry and DNA-based life.

Monod’s hope was that society would come to embrace science and the reality of our chance-driven existence. “Modern societies accepted the treasures and the power that science laid in their laps,” he wrote. “But they have not accepted—they have scarcely even heard its profounder message; the defining of a new and unique source of truth.” After a lifetime of confronting all sorts of menacing isms—Nazism, Stalinism, Communism, and Lysenkoism— truth and the courage to tell it remained the values he cherished most.

In the last months of his life, although weakened by anemia and easily fatigued, he found time to reply to some letters, including one from a 13-year-old boy who asked him for advice on what maxim had helped guide his life. His reply is as fitting now as it was in 1976. “All I can tell you are the qualities that appear most important to me,” Monod answered. “They are: courage, as much moral as physical, as well as the love of truth, or rather, the hatred of lies. I prefer to speak of the hatred of lies rather than the love of truth, since one is never sure of holding the truth, whereas with lies, one is almost always able to detect them, to discover them, and to denounce them.”

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