A contrarian nature, by clearing the field of received wisdom, speeds original thought. Physicists, astronomers, scholars of every stripe, have always been charmed by the counterintuitive—and why not, as it so often turns out to be right? Dyson’s present devotion to a set of contrary, counterintuitive, even counter-obvious ideas on climate change is hardly a novel stance for him, only a little more stubborn than usual. It is clear to me that he has been stung by the criticism of his musings on global warming, and is digging in his heels.
Dyson is prone to conducting thought experiments, and will often slip into one without warning. It is not always apparent when he is inhabiting some Dalí-esque experimental landscape between his ears and when he has touched down on Earth. Even his old colleagues from Project Orion, men working with him on an exceedingly far-out concept, were sometimes unsure.
“Freeman’s last lecture, toward the end of his stay, was a marvelous thing,” an Orion engineer named Brian Dunne told me. “He decided to take Orion to the ultimate. It was funnier than hell. First I didn’t believe it. Then I did. Then I didn’t. It was just so outlandish, beyond anything we had ever envisioned before.”
What Dyson proposed was a 240-million-ton ark with a pusher plate 90 miles in diameter and powered by hydrogen bombs. It was a modest vessel, really, the smallest possible practical version of a class of 6,000-miles-per-second starships he had dreamed up, dreadnoughts capable of crossing our solar system in a month. His starship would be slow off the starting blocks, with a zero-to-6,000-mps time of 30 years, but then it would really get rolling. Dyson addressed small details, like questions of plumbing. Nuclear-pulse propulsion, even in the small, pokey, atom-bomb-powered version of the Orion ship designed to tool around this solar system, required that each nuclear bomb be packaged in propellant—some material that, when vaporized into a plasma stream by the explosion, would strike the pusher plate and provide the necessary kick. For his starship, Dyson proposed recycling the feces of the astronauts as propellant. Riding a thermonuclear shit storm, his ark would carry several thousand colonists to Alpha Centauri on a 150-year voyage.
“Was he serious?” I asked Dunne.
“No,” said the engineer. He laughed merrily at the memory. Then suddenly he stopped. His face went thoughtful. “Well, you never know,” he said. “You can’t tell with Freeman. You have to be cautious.”
“Was he serious?” I asked Ted Taylor several days later. Taylor, an expert in the miniaturization of nuclear bombs, was the head of Project Orion and Dyson’s closest friend on the team.
“I don’t think so,” Taylor said, after several moments of hesitation. “In his characteristic way, he wanted to push something to the limit. H-bombs, per unit of energy, are a lot cheaper than A-bombs. They’re also a lot hotter, a lot more energetic.”
Dyson himself, when I put the same question to him, was dismissive. “The starship was like an existence theorem in math,” he said. “It was to prove if you could do it. I never really believed in it.”
Einstein could not make change, according to the lore; the bus drivers of Princeton had to pick out his nickels and quarters for him. We dimmer bulbs love to seize on tales like this. We are comforted by the notion of the educated fool. It seems only right that some leveling principle should deprive the geniuses among us of common sense, street smarts, mother wit. It is tempting to try explaining Dyson in this way.
Having myself grown up in Berkeley, where Nobel laureates are a dime a dozen, I certainly know the syndrome: the mismatched socks, the spectacles repaired with duct tape, the forgotten anniversaries and missed appointments, the valise left absentmindedly on the park bench. Yet hometown experience did not prepare me completely for Dyson. In my interviews with the physicist, he would sometimes depart the conversation mid-sentence, his face vacant for a minute or two while he followed some intricate thought or polished an equation, and then he would return to complete the sentence as if he had never been away. I have observed similar departures in other deep thinkers, but never for nearly so long.
“He’d just disappear,” George Dyson remembers. George was just 5 when his father moved the family west to La Jolla for the Orion work, but he was a watchful child, and it was his impression that the varied challenges of designing the spacecraft only intensified his father’s preternatural powers of concentration. Freeman’s body occupied the chair in his study, but in every other sense, he was gone.
Many years after Orion, in La Jolla, with the physicist as my guide, I tried to drive us to a restaurant that Dyson knew from his spaceship days. We overshot it by a mile going east, because Dyson got lost in some long chain of cogitation, and then we overshot it going west, and then overshot it going east again. Each time, Dyson would apologize, but remorse did not save him from falling again, just a few yards down the road, into some black pothole of cerebration. Our course to the restaurant, which we finally reached, half-starved, was the sort of oscillation you might chart by affixing a pencil to the tip of a pendulum as it loses momentum. (I chose not to interview Dyson afresh for this essay, not from any impatience with his mental walkabouts, but because what I wanted to address here were his public statements on climate change, the environment, and technology.)
If this seems to support a nutty-professor explanation for Dyson, then the testimony of his colleagues tends to argue the other way. Among his former co-workers, Dyson is famous for a kind of elevated common sense.
The Orion engineer Brian Dunne, a nuts-and-bolts sort of guy, was doubtful at first about Dyson’s pragmatism. “I had had dealings with lots of very eminent theorists,” he told me. “I’d found huge gaps in their knowledge of things, particularly experimental problems—how to put something together that works. When I realized Freeman really is a fine engineer, I was astounded. He knows electrical engineering, mechanical engineering, structural. That’s unnerving, in a theoretical physicist with the eminence that he enjoys. His contributions to quantum electrodynamics are classics. They are beautiful pieces of work—poetry in physics, if you will. To see the same man do an analysis of the pusher-plate motion, and the shock-absorber motion, putting in the damping coefficients, and the strengths and stresses, and getting it all right—that’s unnerving.”
Dyson eludes stereotype. The nutty-professor hypothesis, as applied to him, remains a work in progress.
Some critics have suggested that at his advanced age, Dyson is “out of his beautiful mind,” as one put it. On most subjects, Dyson’s recent writings and lectures give no hint that he is slipping. He puts his words and thoughts together as lucidly as ever. When a mind starts out with all the excess computing power that Dyson’s did, it generally has enough millions of spare neurons to carry the owner into his 90s and across the finish line in style. I would venture that if Dyson’s mind is lost, or just wandering far afield in its idiosyncratic way, then that detour happened long ago, and age has nothing to do with it.
“First I have to clear away a few popular misconceptions about space as a habitat,” he said, lecturing in London in 1972, when he was only 48. “It is generally considered that planets are important. Except for Earth, they are not. Mars is waterless, and the others are, for various reasons, basically inhospitable to man. It is generally considered that beyond the sun’s family of planets there is absolute emptiness extending for light-years until you come to another star. In fact, it is likely that the space around the solar system is populated by huge numbers of comets, small worlds a few miles in diameter, rich in water and the other chemicals essential to life.”
The comets contain everything we need except warmth and air, he promised, and he predicted that biological engineering would make up for these two shortcomings: bio-engineers would design trees that function in airless space and thus make the comets habitable. Then he turned to potential habitations much closer at hand:
“There’s very good news from the asteroids. It appears that a large fraction of them, including the big ones, are actually very rich in H2O. Nobody imagined that. They thought they were just big rocks … It’s easier to get to an asteroid than to Mars, because the gravity is lower and landing is easier. Certainly the asteroids are much more practical, right now. If we start space colonies in, say, the next 20 years, I would put my money on the asteroids.”
The real-estate mantra “Location, location, location” applies to the asteroids, as it does everywhere else. The near-Earth asteroids seem particularly prime. And Dyson has had his eye on them for a very long time.
Eros, the first near-Earth asteroid discovered and the second-largest of them all, is promising terrain. Eros is a Mars-crosser. It is named for the god of love. Shaped something like a sweet potato, or a cashew, it is 21 miles long by eight wide by eight deep—somewhat bigger, astronomers think, than the asteroid that dug the Chicxulub crater out of the Yucatán Peninsula and wiped out the dinosaurs. The Erotic climate is not perfect. Temperatures rise to 212 degrees Fahrenheit in daytime and drop to minus 238 degrees at night. Gravity there is unsettled, fluctuating wildly depending on where you stand. But Eros does have redeeming features. More gold, silver, aluminum, zinc, and other precious metals lie near its surface, in theory, than exist in all the Earth’s crust. Eros was the first asteroid on which a spacecraft ever landed. In 2001, after orbiting Eros for a year, the robotic probe Shoemaker set down on the rubble of the Erotic surface. The probe sits there still. For future colonists, it may prove useful—a historical monument, perhaps, or just scrap.
Dyson has been thinking about Eros for most of his life, and in his imagination, he anticipated the Shoemaker’s landing by nearly 70 years. Among the relics of his childhood is a blue exercise book, its cover reading, in fountain pen, Sir Phillip Roberts’s Erolunar Collision. Written by F. J. Dyson, aged 8–9, 1932–1933. The story opens:
Chap. I. The Great Discovery
Sir Phillip Roberts, director of the British South-African Astronomical Society, was sitting in his study, calculating facts about Eros, the minor planet which revolves at between 100,000,000 and 180,000,000 miles from the sun, and which sometimes approaches within 13,000,000 miles of the Earth; He had just discovered that Eros was going to come exceptionally near to the Earth in 10 years and 291 days, and might, by some luck, be caught within the Earth’s attraction. He quickly went off and told one of the members of the society, Major Forbes, who was rather a friend of his, the good news.
There is very little action in “Sir Phillip Roberts’s Erolunar Collision,” but a great deal of calculating. (“This set everybody calculating exactly where the Moon would be at that time, and, wonder of wonders!, the Moon was found to be due at the exact spot where Eros would be in 10 years, 285 days’ time; or, to put it more shortly, Eros would collide with the Moon.”) Sir Phillip Roberts and his astronomer colleagues, having determined that Eros will hit the moon, set about designing a craft that will take them there in time to observe the crash. (“‘Well,’ said Sir Phillip, ‘we are here to converse about our projectile inside which we are to ascend to our only satellite; what size do you prepose?’”)
My point here is not that this fictional projectile eerily foreshadows Dyson’s work on the Orion spaceship—though foreshadow it certainly does. My point is that the physicist was not in his 80s and fading when he lost his beautiful mind in the asteroids. He was just 8 years old.