Freeman Dyson’s Disturbing Scientific Theology

Physicist Freeman Dyson proposed an intriguing solution to the old problem of evil: if God created us, and loves us, why is life so painful? I found this photo on Wikipedia.

Hoboken, June 9, 2024. Recent advances in artificial intelligence have given new life to the old idea that one day intelligent machines will surpass their human creators. Physicist Freeman Dyson was an early explorer of this sci-fi scenario. Dyson, who died in 2020 at the age of 96, possessed one of the most brilliant, original minds I’ve ever encountered, a mind that no machine will ever match. Below is an updated version of my profile of Dyson in The End of Science. –John Horgan

Humanity, Nietzsche proclaimed, is just a steppingstone, a bridge to the Superman. If Nietzsche were alive today, he would surely entertain the notion that the Superman might be an intelligent machine.

There is, it turns out, an odd little scientific field that speculates about how intelligence will evolve if it sheds its mortal coil. I call this field scientific theology because it explores age-old philosophical and even theological questions: Why are we here? What are the ultimate limits of knowledge? Is suffering a necessary component of existence, or can we attain eternal bliss?

Freeman Dyson is the most brilliant practitioner of scientific theology. In his 1988 essay collection Infinite in All Directions, Dyson ponders why life is so hard. The answer, he suggests, might be related to “the principle of maximum diversity.” This principle, he explains,

operates at both the physical and the mental level. It says that the laws of nature and the initial conditions are such as to make the universe as interesting as possible. As a result, life is possible but not too easy. Always when things are dull, something turns up to challenge us and to stop us from settling into a rut. Examples of things which made life difficult are all around us: comet impacts, ice ages, weapons, plagues, nuclear fission, computers, sex, sin and death. Not all challenges can be overcome, and so we have tragedy. Maximum diversity often leads to maximum stress. In the end we survive, but only by the skin of our teeth.

When I first read this passage, I circled it and drew exclamation marks beside it. Dyson is rejecting the notion that physics can find a “final theory” that solves the riddle of the universe and brings physics to an end. Dyson is also hinting at a solution to the deepest of all theological puzzles, the problem of evil: Why would a loving, all-powerful God create such a painful, unjust world?

Dyson’s answer is that God makes life hard to ensure that it will be “as interesting as possible.” The implication is that existence is--and must be--an eternal struggle. Was I reading too much into Dyson's remarks? I hoped to find out when I interviewed him in 1993 at the Institute for Advanced Study, his home since the early 1940s.

Dyson is a slight man, all sinew and veins, with a cutlass of a nose and deep-set, watchful eyes. He resembles a gentle raptor. His demeanor is cool and reserved--until he laughs. Then he snorts through his nose, shoulders heaving, like a 12-year-old schoolboy hearing a dirty joke. It is a subversive laugh, the laugh of a man who insists that science at its best is “a rebellion against authority.”

I don’t bring up Dyson’s maximum-diversity idea right away. First, I ask about his career choices. Dyson was once at the forefront of the quest for a unified theory of physics. In the early 1950s, he helped invent the quantum theory of electromagnetism, which became part of the standard model of particle physics.

Then Dyson turned to problems that, some colleagues claim, were unworthy of his talents. When I mention this criticism, Dyson responds with a tight-lipped smile. He notes that physicist Lawrence Bragg was “a sort of role model.” After Bragg became director of the University of Cambridge's legendary Cavendish Laboratory in 1938, he steered it away from nuclear physics, on which its reputation rested, and into new territory.

“Everybody thought Bragg was destroying the Cavendish by getting out of the mainstream,” Dyson says. “But of course it was a wonderful decision, because he brought in molecular biology and radio astronomy. Those are the two things which made Cambridge famous over the next 30 years or so.”

Dyson, too, has spent his career swerving into new territory. He veered from mathematics, his focus in college, to quantum physics and from there to nuclear engineering, arms control, climate studies--and speculation about the long-term evolution of intelligence.

Dyson was provoked into taking up this final topic by Steven Weinberg’s notorious remark that “the more the universe seems comprehensible, the more it also seems pointless.” No universe with intelligence is pointless, Dyson retorts in a 1979 paper in Reviews of Modern Physics. He proposes that in an eternally expanding universe, intelligence can persist forever--perhaps in the form of a cloud of charged particles--through shrewd conservation of energy. 

In Infinite in All Directions, Dyson predicts that the entire universe might eventually be transformed into one great mind. He addresses a question this prophecy raises: “What will mind choose to do when it informs and controls the universe?” The question, Dyson makes clear, has theological implications:

I do not make any clear distinction between mind and God. God is what mind becomes when it has passed beyond the scale of our comprehension. God may be considered to be either a world-soul or a collection of world souls. We are the chief inlets of God on this planet at the present stage in his development. We may later grow with him as he grows, or we may be left behind.

Dyson insists that even a cosmic superintelligence cannot solve the riddle of existence. There will “always be new things happening, new information coming in, new worlds to explore, a constantly expanding domain of life, consciousness and memory.” The quest for knowledge will be--must be—“infinite in all directions.”

Dyson admits that his views reflect wishful thinking. When I ask if science can keep evolving forever, he replies, “I hope so! It's the kind of world I'd like to live in.” The history of knowledge-seeking gives Dyson hope. More than two thousand years ago, “very bright people” invented something that, while not science in the modern sense, was its precursor.

“If you go into the future, what we call science won't be the same thing anymore, but that doesn't mean there won't be interesting questions.” Dyson cites Kurt Gödel’s famous proof that every mathematical system poses questions that cannot be answered within that system. “Since we know the laws of physics are mathematical,” Dyson says, “and we know that mathematics is an inconsistent system, it’s sort of plausible that physics will also be inconsistent” and therefore open-ended.

Dyson grants that Hawking, Weinberg and others predicting the “end of physics” may turn out to be “right in the long run. Physics may become obsolete. But I would guess myself that physics might be considered something like Greek science: an interesting beginning but it didn't really get to the main point. So the end of physics may be the beginning of something else.”

When, finally, I ask Dyson about his principle of maximum diversity, he grimaces and shrugs. Oh, he didn’t intend anyone to take that idea too seriously. He is not really interested in “the big picture”; one of his favorite quotes is "God is in the details."

But doesn't he find it disturbing, I persist, that many scientists seem compelled to reduce the immense diversity of things to a single explanation, such as string theory? Don't such efforts represent a dangerous game, which might bring our knowledge-seeking to a halt?

Dyson smiles, as if he finds my obsession with his idea amusing. "Yes, that's true in a way," he replies, “I never think of [maximum diversity] as a deep philosophical belief," he adds. "It's simply, to me, just a poetic fancy."

Dyson is no doubt just maintaining a little ironic distance between himself and his “poetic fancy.” I nonetheless find his dismissal of maximum diversity frustrating, and even disingenuous. Throughout his career, Dyson has adhered to the principle of maximum diversity; that is why he keeps veering away from mainstream thinking in physics and other fields.

Dyson’s principle of maximum diversity is also a profound, and disturbing, solution to the problem of evil, one that I stumbled on during a scary psychedelic trip in 1981. Even if the cosmos was designed for us, Dyson suggests, we will never figure it out, because not even God, if there is a God, can figure it out. Nor will we ever create a blissful paradise, or utopia, in which all our problems are solved. Without “challenges” like wars, genocides, plagues, nuclear weapons and superintelligent machines, life would be too boring.

This is a chilling answer to the problem of evil, but I haven’t found a better one.

Further Reading:

Check out my chapter on scientific theology in The End of Science.

And here are some related columns:

The Delusion of Scientific Omniscience

My Doubts about The End of Science

Conservation of Ignorance: A New Law of Nature

Sabine Hossenfelder, The End of Science and My Quantum Experiment

What Is It Like to Be God?