Physics and Philosophy: Or, How Stephen Hawking Learned to Stop Worrying and Love the Big Bang

“[P]hilosophy,” Stephen Hawking famously claimed, “is dead.” “Philosophy,” he argued, “has not kept up with modern developments in science, particularly physics. Scientists have become the bearers of the torch of discovery in our quest for knowledge.”

Werner Heisenberg might well have agreed with Hawking, though again he might not have. We cannot be certain. After all, Heisenberg was himself both a physicist and a philosopher, though he was the former before he was the latter. In fact, the title of this article, “Physics and Philosophy,” was Heisenberg’s before it was mine. He used it 65 years ago as the title of his Gifford Lectures, in which he grappled with the philosophical implications of quantum theory, and especially of his eponymous Heisenberg uncertainty principle, which states that (in Stephen Hawking’s words) “a particle has neither a definite position nor a definite velocity unless and until those quantities are measured by an observer.”

Classical physics was (and remains) deterministic; quantum physics, Heisenberg recognized, reintroduced something akin to free will, or at the very least acknowledged that the human action of observation has an effect on that which the observer has observed — a decidedly philosophical concept.

About 25 years after Heisenberg delivered his Gifford Lectures, the Reverend Richard Rehm delivered a sermon at Christ Community Church in Spring Lake, Michigan. I was sitting in the pews with my trombone — not because I was an odd teenager, but because our public high-school band had been invited to play hymns during a Christmas service. Christ Community was a congregation in the Reformed Church in America, and I was, then as now, a Catholic, but I sat in rapt fascination as the Reverend Rehm, a few years before Stephen Hawking declared philosophy dead, essentially proclaimed the death of theology (though he didn’t phrase it that way).

Physicists, the Reverend Rehm declared, were more likely to discover God than theologians were. As they pursued the holy grail of a grand unified theory of physics, they were, he argued, entering into the mind of the god who had created the universe that this grand unified theory would ultimately define.

To a bright young student who loved mathematics and science and was considering majoring in physics in college, the Reverend Rehm’s words were as tempting as the serpent’s were to Eve. No greater pride hath a teenager than this: to think that he might discover God Himself. In no small part because of this particular sermon, I entered Michigan State a few years later as a physics major, though I switched to political theory after a single term.

About five years after I took a bite out of the apple that the Reverend Rehm had offered me, Russell Kirk, the great conservative thinker who would, over the next half-decade, become one of my mentors, told me that he thought that we were about to enter a new age of faith that would be ushered in by scientists — and, in particular, by physicists — who would prove the existence of God. Since it was the first time we had ever met, I did not have the courage to tell him that I knew that he was wrong.

For by then — even at the still young age of 21 — I had realized that a god who could be summed up in equations would no god at all. “The heavens proclaim the glory of God, and the firmament shows forth the work of His hands” — but equating God with the laws that govern the world He has created ultimately subordinates Him to His creation.

Stephen Hawking, of course, was not a believer. In fact, in October 1981, at (of all places) a meeting of the Pontifical Academy of Sciences, he had introduced his “no boundary” hypothesis of the universe, which accepted the idea of the Big Bang but, he argued, removed the need for a Prime Mover to have set the Big Bang into motion. As he wrote seven years later in his most famous work, A Brief History of Time, in the “no boundary” hypothesis “The universe would be completely self-contained and not affected by anything outside itself. It would be neither created nor destroyed. It would just be. … What place then for a creator?”

And yet, as his former student and frequent collaborator Thomas Hertog shows in his recent book On the Origin of Time: Stephen Hawking’s Final Theory, Hawking spent much of his life trying to discover the physical theories that the Reverend Rehm equated with the workings of the mind of God and that Russell Kirk thought might lead us to a new age of faith.

It is hard to overstate the enduring grip that the classical view of physics had on some of the greatest minds in physics even after the formulation of quantum mechanics. All too many Christian writers have misquoted Albert Einstein as saying that “God does not play dice with the universe” in an attempt to enlist his authority on behalf of belief in God. But what Einstein was actually expressing, in a letter to quantum theorist Max Born, was his resistance to quantum theory, because quantum theory undermines the determinism of classical physics (even as modified by Einstein’s own theory of relativity). Einstein used, not the word “God,” but the term “the Old One” as a metaphor for unchanging physical laws. Indeed, he had vehemently argued against Abbe Georges Lemaitre’s theory of the Big Bang because, as he told Lemaitre, “this reminds me too much of the Christian dogma of creation.” He preferred a universe with no beginning and no end, governed always by those same unchanging laws that, he was certain, physicists would one day fully discover.

Decades later, Hawking too had trouble shaking loose from the mindset imparted by classical physics. The “no boundary” hypothesis emerged from Hawking’s attempt to extend quantum theory to the macro world of phenomena described by the laws of classical physics. And from that emerged the view of the universe as a quantum wave function, a superposition of every possible state of every particle in the universe that extended the uncertainty principle to a macro level.

Yet even so, for another 20 years, Hawking clung to what he would eventually call a “God’s eye view” of cosmology, which assumed, Hertog writes, “that the mathematical laws of physics had some sort of existence that superseded the physical reality they governed.” It wasn’t until August 2002 that Hawking finally broke through the remaining grip of classical physics once and for all. “Time to stop playing God,” he told Hertog. “We need a new philosophy for cosmology.”

Over the course of two decades, the “no boundaries” hypothesis had revolutionized physics, leading to, among other things, a multitude of theories of the multiverse, all of which Hawking adamantly rejected. He had intuited all along that there was something wrong with those theories, but only now could he fully articulate the problem. “The universe as we observe it,” he told Hertog, “is the only reasonable starting point in cosmology.” But that has, Hawking realized, serious philosophical implications. “We are not angels, who view the universe from the outside. We and our theories are part of the universe we are describing.” As Hertog writes, in this view, “cosmology is laboratory science inside out — we are within the system, looking up and looking out.”

In one sense, we might say that Hawking was late to the game. Heisenberg had already pointed in this direction in Physics and Philosophy, and two decades later (and 23 years before Hawking) the theoretical physicist John Archibald Wheeler had laid bare the philosophical implications of quantum theory:

We had this old idea, that there was a universe out there, and here is man, the observer, safely protected from the universe by a six-inch slab of plate glass. Now we learn from the quantum world that even to observe so minuscule an object as an electron we have to shatter the plate glass; we have to reach in there …

The physicist, Wheeler pointed out,

must install his chosen measuring equipment. It is up to him to decide whether he shall measure position or momentum. To install the equipment to measure the one prevents and excludes his installing the equipment to measure the other. Moreover, the measurement changes the state of the electron. The universe will never afterward be the same.

“To describe what has happened,” Wheeler concluded, “one has to cross out that old word ‘observer’ and put in its place the new word ‘participator.’ In some strange sense the universe is a participatory universe.”

Indeed, as early as the 1950’s and 1960’s some nonphysicists had taken note of, and expounded upon, the philosophical implications of a participatory universe, including C.S. Lewis’s and J.R.R. Tolkien’s friend Owen Barfield (most famously in Saving the Appearances) and my mentor and friend John Lukacs, in Historical Consciousness: The Remembered Past. Both had pointed out that we are not only part of the universe; the universe, as we experience and understand it, is inseparable from our human consciousness. It is this philosophical insight that Hawking imported back into cosmology when he noted to Hertog that “Our theories are never fully decoupled from us.”

If Heisenberg and Wheeler and Barfield and Lukacs and Hawking were right, Albert Einstein’s argument against quantum theory — that “Physics is an attempt to grasp reality as it is, independently of its being observed” — was wrong because it describes something that simply is not possible. As Niels Bohr had put it, “No phenomenon is a real phenomenon until it is an observed phenomenon.”

For decades, cosmological theorizing had started at the Big Bang and moved forward (a “bottom-up” view that Hawking himself had previously embraced, including in his “no boundary” hypothesis). But the bottom-up view had led to the maddening confusion of multiverse theory: If the universe can be described as a quantum wave function in which every possible outcome exists simultaneously until an act of observation causes a branching and the creation of another effectively infinite set of multiverses, how are we ever to find the universe that we actually inhabit?

Recognizing now that “The universe as we observe it is the only reasonable starting point in cosmology,” Hawking proposed a “top-down” view that moves backward in time from what we currently observe. As novel as this view was in cosmology, it is not, Hertog notes, without precedent in science: This is how evolutionary history is determined in the biological sciences.

But as we move backward in time, history becomes in some fundamental sense contingent on us. As Hawking told Hertog, “The history of the universe depends on the questions you ask.” History, like our theories, is “never fully decoupled from us,” because it is, in the words of John Lukacs, “the remembered past.” “Any kind of tangible past in top-down cosmology,” Hertog writes, “is always an observer’s past.” And thus, Hertog argues, “In a quantum universe — our universe — a tangible physical reality emerges from a wide horizon of possibilities by means of a continual process of questioning and observing.” “This observership, the interactive process at the heart of quantum theory that transforms what might be into what does happen, constantly draws the universe more firmly into existence.” Or, as Hertog sums up Hawking’s top-down view, “We create the universe as much as the universe creates us.”

The scientific revolution, it has often been said, removed man from the center of the universe. Five hundred years later, his top-down cosmology, Hawking realized, “put humankind back in the center.” Yet in doing so, it also puts us in our proper place, ontologically speaking. In adopting a God’s eye view of the universe, mankind had attempted to usurp the place of our Creator, to subordinate Him to the grand unified theory we were convinced that we would one day create. Restored to our proper place, we can see ourselves as Saint Augustine saw us: as co-creators with God of the universe He created for us.

Stephen Hawking never became a Christian, but after he proposed his top-down cosmology, he took Thomas Hertog to a production of Wagner’s Götterdämmerung at the Royal Opera House to mark, as he told Hertog, “the end of my battles with God.” And 35 years after he unveiled his “no boundary” hypothesis at the Pontifical Academy of Sciences, he returned to the Vatican to announce that “The universe may have a boundary after all.” In November 2016, Hertog writes, “there were no more battles with God or the pope to be fought. Quite on the contrary, Stephen found a strong and moving resonance with Pope Francis in their shared goal of protecting our common home in the cosmos for the benefit of humanity today and tomorrow.”

The death of philosophy, it appears, has been greatly exaggerated. And even the most prominent scientist of recent decades may have found a place for a creator, beyond mankind’s laws of space and time.

First delivered as a paper to the Cosmopolitan Club of Huntington County, Indiana, on October 17, 2023.