Harold C. Urey: Science, Religion, and Cold War Chemistry

Life in the atomic age, 1962. Schoolchildren in St. Petersburg, Florida, practice a duck-and-cover disaster drill. (Bettmann/CORBIS)

Life in the atomic age, 1962. Schoolchildren in St. Petersburg, Florida, practice a duck-and-cover disaster drill. (Bettmann/CORBIS)

Religion without God

Despite Urey’s assertion of the importance of religion in his public speeches, he did not himself become more religious—at least not in the conventional sense. His life’s story was one of a movement away from religion.

The story Urey told in “The Intellectual Revolution”—of scientists raised within religious homes to be moral and honest and then bringing these morals agnostically to their research—was the story he had lived. Urey was born into a family of ministers of the Church of the Brethren, which was at the time a conservative and agrarian Christian denomination.

From high school on, Urey struggled to distance himself from his religious upbringing. On the rare occasions when he spoke about his childhood, he presented himself as the quintessential American farm boy. Rather than highlight the peculiarities of being raised in one of the original Pennsylvania Dutch religions, he instead presented himself as having emerged from “among the ordinary, common people of the United States.”

Urey did not speak or write often about his own view of God. When asked whether his scientific education had eroded or strengthened his faith in God, Urey might respond as he did to one admirer’s letter: “I myself have my own definitions of God and things of this sort, but I would not like to discuss them in public at all.” In his unpublished autobiography he admitted that he did not believe in an afterlife and believed instead that “we are all temporary, and are only part of this enormously complex universe that changes with time.” In a public forum, after reciting from memory the first chapter of Genesis, Urey said it was “beautiful poetry” but that he was more convinced by the evidence for evolution.

When Urey did invoke God, it was a God who had done little more than set the universe in motion. Urey told his pious mother and stepfather, much to their dismay, that he preferred to believe in a “God [who] opened his hand and the universe was created.” As he explained to the editor of This Christian Century, it was simply “more beautiful to have a universe that is established in such a way that it takes care of itself completely by itself than it is to assume otherwise.”

Urey told one audience that the universe was like a god: “Now this God is a God that extends in all directions from billions of light years and has existed for billions of years and will exist for billions of years in the future and maybe all these numbers should be infinite. This God has left a true record in nature which we can read while exercising some diligence.”

Ultimately, it was the universe that inspired Urey: “To me, the enormous universe and all the things in it are the source of my wonder, and I need no God to increase this wonder at all.” Urey was content to believe that the universe, beginning with the Big Bang, had proceeded to unfold and evolve without the intervention of God and that life had emerged on Earth through chance chemical events.

One Great Cloud

Urey called for a “new prophet” to create a unifying vision for science and religion, but he knew that this would not be his role. As a skeptical scientist he felt that the best he could do was investigate and contribute to the inspirational story of humankind’s place in the universe. One of his last scientific projects—conducted under the auspices of NASA’s lunar exploration program—aimed to do this on a grand scale.

In the 1950s Urey proposed that the Moon was something like a cosmochemical fossil—one whose formation dated to the very beginning of the solar system. Such an object might reveal the chemical starting point from which the Sun and planets evolved. Urey’s ideas influenced NASA’s emerging lunar-science program. As the Space Age began, Urey eagerly participated in NASA’s robotic and manned exploration of the Moon. He even analyzed lunar rocks returned by the Apollo astronauts.

As a group of lunar scientists told the Washington Post during the Apollo program, “Uncle Harold is the real modern father of lunar science.” But the Moon turned out to be not what Urey expected, and no consensus over its origin emerged during his life. The Moon would be of little use to him in building the detailed chemical history of the solar system he had hoped to construct.

NASA’s lunar missions ended in 1972. Soon after, Urey’s eyesight failed, which, along with declining health that included the onset of Parkinson’s disease, robbed him of his ability to work. In 1977 he wrote to his old friend, physicist Raymond T. Birge: “I am feeling my old age every day. My hands quiver, I wobble when I walk, my eyesight is bad, and I can’t remember things so that I cannot keep up with the literature, hence I can do no scientific work at all.”

Reflecting on his life in science, Urey had mixed feelings. On the one hand, science had fulfilled many of its promises: “Think of the things that have happened in this century,” he wrote to Birge. “Almost the entire development of radioactivity has happened in this century.” But at the same time, Urey was plagued by the uncertainties unleashed by the century’s great developments. He asked Birge, “Do you think people will be here a million years from now, or even a century from now? . . . I wonder if we have not lived through an exceedingly interesting time and just before a very dreadful time when problems and disaster will plague men on the earth.”

Urey died in 1981, eight years before the fall of the Berlin Wall and the end of the Cold War. In one of his final speeches, to the graduating seniors of McGill University, he said that despite his and his colleagues’ professional success and prosperity he did not feel confident that they were leaving the world better than they had found it. There had been triumphs, but “one great cloud”—the atomic threat—still hung over their heads. At the end of his own career he could only wish the younger generation luck in clearing the cloud away.

Matthew Shindell is a postdoctoral research fellow at the University of Southern California and was the 2009–2010 John C. Haas Fellow at CHF. His research focuses on the development of American earth and planetary science during the Cold War.