Born in Crowthorne in 1923, Freeman Dyson spent most of his career at the Institute for Advanced Study in Princeton, where he tackled problems stretching across physics, engineering, mathematics and statistics. Recognised early on in his childhood as a prodigy, Dyson won a scholarship at 17 to study Pure Mathematics at Trinity College, Cambridge. During his time there, which coincided with World War II, Dyson was assigned to the Operational Research Section of the RAF Bomber Command and was responsible for calculating optimal bomber formations. This became an extremely upsetting experience for Dyson, who felt his work on “how to murder most economically” created an “emptiness of the soul,” but it was also a formative one. Dyson’s wartime experience made him extremely aware of the intimate relationship between science and social justice and drove him towards projects where science could be used for good throughout the rest of his life.

In 1947, Dyson moved to Cornell University for postgraduate study with nuclear physicist Hans Bethe, where he made his arguably greatest contribution to fundamental science. At the time, three seemingly different formulations of quantum electrodynamics had been proposed by Richard Feynman, Julian Schwinger and Shinichiro Tomonaga. As most physicists struggled to discern which was correct, Dyson demonstrated that the three were, in fact, equivalent. Hailed by Richard Feynman as the “jewel of physics,” Dyson’s demonstration was the foundation of the theory of quantum electrodynamics, which paved the way for modern computers, digital cameras and radiation therapies for cancer.

“Rebellion is vital within science as a catalyst for new knowledge production”

Even without a doctorate, Dyson soon received fellowship offers from elite institutes around the world, ultimately accepting one from Robert Oppenheimer himself to join the Institute for Advanced Study. However, despite this widespread recognition, Dyson was passed over for the 1965 Nobel Prize, which was instead awarded to Feynman, Schwinger and Tomonaga. While this decision outraged many in the scientific community, whenever asked for his opinion, Dyson simply said, “if you want to win a Nobel Prize, you should have a long attention span, get hold of some deep and important problem and stay with it for ten years. That wasn’t my style.”

Instead, Dyson said, “I look for puzzles. I look for interesting problems that I can solve. I don’t care whether they’re important or not...I’m definitely not obsessed with solving some big mystery.” Dyson’s unique “style”, as well as an unparalleled self-awareness and intense drive to use science and technology for social justice, led Dyson to work on projects from designing a nuclear reactor TRIGA, used in hospitals to diagnose metabolic diseases, to developing a cheap and portable mine detector. Dyson’s sense of social responsibility was never clearer than when he testified in support of the nuclear-test-ban treaty between the US and USSR, despite having worked devotedly for Orion, an Air Force project designing a spacecraft powered by exploding atomic bombs that would be terminated by the treaty.

“Science needs its contrarians and rebels to generate the diversity of ideas required for scientific progress”

Though he claimed to be “much more of a conformist,” it is hard to ignore the streak of rebellion in Dyson. His distinct puzzle-solving approach to research directly counters the conventional paradigm of how scientists work and advance in their fields. More explicitly, Dyson has, in many of his popular science books, posited rebellion as central to the ability of science to better both society and science itself. In his collection of essays, The Scientist as Rebel, Dyson advises parents “to introduce our children to science today as a rebellion against poverty and ugliness and militarism and economic injustice.” Not only is rebellion a valuable driving force behind the role of science within society, Dyson asserts that rebellion is vital within science as a catalyst for new knowledge production. Whether ironic or fitting, it was his role as a scientific contrarian that ultimately landed Dyson in much publicised controversy in the final years of his life.

In 2005, Dyson began publicly stating his misgivings about whether climate change was a pressing issue, announcing that “all the fuss about global warming is grossly exaggerated.” While agreeing that there were rising atmospheric carbon-dioxide levels caused by human activity, Dyson believed warming to be local, not global, and doubted the severity of climate change’s impact on humans and the biosphere. His convictions about climate change were grounded in his own climate models and observations of a deficiency in convincing data. Going against consensus did not bother him in the slightest. Dyson believed that the deeper discord was between those who allege that “any gross human disruption of the natural environment is evil” and those who hold that conserving the biosphere is less important than fighting other evils such as war and poverty. In other words, Dyson simply did not see enough evidence to convince him that climate change was a significant enough problem to divert resources from more pressing issues.

Dyson has said that he did not want his legacy to be defined by his views on climate change. For both his sake and the sake of future generations of scientists, I hope for this as well. While Dyson’s dissension from climate change orthodoxy is significant and perhaps even dangerous given his stature, it is just as dangerous to allow the public disavowal of such an eminent scientist for the singular reason that he, rightly or wrongly, spoke against a certain consensus. It is important to recognise that Dyson’s reservations about climate change came from a lifetime of experience.

Despite the unorthodoxy of his position on climate change, Dyson was a good scientist and, like any good scientist, asked hard questions. As a good scientist, Dyson acknowledged that he was just as likely to be a lonely prophet as he was dead wrong, and, as a good scientist, he did not care. Science needs its contrarians and rebels to generate the diversity of ideas required for scientific progress. Ultimately, as long as science is anchored by social responsibility, it is the direction in which science progresses and the fruits it bears along the way that matter.