Hawking held a revered position in the global intellectual community, with many considering him to be “the most outstanding theoretical physicist since Einstein.” This is not only because of his scientific achievements, but also due to his philosophical and theological contemplations—though his theology was anti-theistic. When reading A Brief History of Time, it becomes evident that Hawking’s primary role as the author is not merely that of a scientist, but more so as a philosopher and theologian.
As a scientist, Hawking proposed a specific quantum gravity theory in A Brief History of Time, aiming to unify general relativity with quantum mechanics. In an effort to solve the technical difficulties of Feynman’s path integral method in quantum mechanics, he introduced “imaginary time,” extending Euclidean spacetime to infinity. As a result, time and space no longer existed as separate, isolated entities. This not only avoided the collapse of physical laws at singularities, but also allowed for the universe’s spacetime structure to be described as “finite but unbounded,” meaning there was no definitive beginning or end. Hawking likened this model of the universe to Earth: from the perspective of real time, the universe’s “beginning” (the Big Bang) is akin to Earth’s North Pole, while its “end” (the Big Crunch) is like the South Pole. Geometrically, the North and South Poles are not distinct; likewise, from the perspective of imaginary time, the universe’s beginning and end are simply human-defined concepts. For Hawking’s quantum gravity model to solidify as a sound scientific theory, it still needs to be observable, verifiable, and proven—a long road from hypothesis to confirmation.
As a philosopher, Hawking expressed strong dissatisfaction with modern philosophy in A Brief History of Time. Philosophy, according to Aristotle, is the love of wisdom, which begins with wonder and leisure. When familiar phenomena suddenly seem different, and we have the time to inquire about these differences, philosophy begins. We want to know who we are, what our purpose is, and to understand the nature of the world, the essence of the universe, and how it evolved from the past to the present, and where it will lead in the future. These grand questions occupied most traditional philosophers’ time. However, as Hawking criticized, since the 19th century, the specialization and mathematization of science have left philosophers unable to keep pace with the progress of scientific theory. They seem to have forgotten the questions posed by their predecessors and instead focus solely on the expression of language. Even one of the greatest philosophers of the 20th century, Ludwig Wittgenstein, declared that the task of philosophy was merely linguistic analysis. Hawking criticized this as a degradation.
As a philosopher, Hawking sought to revive the grand themes abandoned by 20th-century Anglo-Saxon philosophy. He wanted to provide a theory of everything—from our understanding of the universe, time, and space, to the Big Bang, the fundamental forces of the universe, elementary particles, black holes, the arrow of time, and the origin and fate of the cosmos, all the way to the unification of physics. In this sense, Hawking’s popular science works, such as A Brief History of Time and The Grand Design, are undeniably philosophical works, particularly in the domain of the philosophy of science and scientific thought.
From a philosophical perspective, Hawking was a proponent of model realism. Unlike naive realism, which asserts that we perceive the world directly, model realism holds that our descriptions of facts depend on theoretical models, and all observations are imbued with theoretical constructions. In the best case, we can never know how the world truly is; but if a theory predicts accurately, we can reasonably assume that it reflects reality. Thus, Hawking was a modern version of a Kantian philosopher, but with a twist: the model is not preordained and can be chosen freely.
Hawking was also an anti-theistic theologian. The central topic in A Brief History of Time is actually theological: does our universe need God? There is a famous video of physicist Yang Zhenning in which he reflects that as a young man, he did not believe in a creator, but later came to think there must be a creator, to explain certain features of the world, such as the beauty of Maxwell’s equations. Similarly, Einstein held a Spinozist religious view, even asserting that only those with genuine religious sentiment could become true scientists. Looking through the history of science, it is difficult to find a great scientist without some sense of the divine, though they often did not believe in a personal deity or anthropomorphic God.
However, Hawking likely contradicts this view. One of the key missions of A Brief History of Time is to expel God from the universe—not only by rejecting a personal creator, but by asserting that no creator is necessary at all. We live in this world, curious about everything around us, so we construct theories to describe it. Theories can be good or bad, but a good theory must make predictions that can be tested by experience. Thus, myths, magic, and ideologies are excluded from science. A good theory should also exclude emotions and will, because following the laws of nature is different from obeying human laws or moral codes. The former does not depend on emotion or will, and therefore teleology is excluded. In the early 19th century, Laplace’s determinism, built on Newton’s laws, believed that if we knew the laws and the state of the universe at a given moment, we could predict its future evolution, rendering God’s intervention unnecessary. The role of God became confined to the selection of initial conditions and universal laws. The development of quantum mechanics in the 20th century shook this determinism, showing that the universe’s evolution is not completely determined, at least not as Laplace imagined. However, the initial conditions and laws of the universe still remain unexplained. According to general relativity, time originated at a singularity where all physical laws broke down. Thus, God would have total freedom to choose how the universe began. However, if Hawking’s version of quantum gravity is correct, the universe is eternal, with no beginning or end, meaning there would be no initial conditions for God to choose.
Nevertheless, Hawking did not entirely rule out the possibility of God’s existence. He acknowledged that the universe requires a set of laws, but no sufficient explanation was provided for these laws. Hawking stated that even if God exists, His freedom would be severely limited, because there may only be a few complete theories that can explain the existence of the entire universe. However, he also recognized a fundamental dilemma: even if such laws exist, they are merely rules and equations, mathematical models. How can a mathematical model generate a real universe? This dilemma points to the gap between mathematics and physics. We are familiar with this gap. Laozi said: “One gave birth to two, two gave birth to three, and three gave birth to all things.” It is easy to understand how numbers give birth to numbers, but it is hard to grasp how an endless sequence of numbers could generate “things.”
This suggests that while Hawking succeeded as a scientist, if his quantum gravity theory is proven experimentally, he still did not completely expel God. On the issue of God, A Brief History of Time maintains an inconsistent stance. In some parts, Hawking recounts with interest his experience at a Vatican conference, where the Pope told the attendees that they could study the events after the Big Bang but should not inquire about the Big Bang itself, as it was the moment of creation and a matter for God. Hawking expressed some satisfaction at that time, as his theory suggested no such moment existed. He also felt a strong identification with Galileo, who opposed the church’s orthodoxy and was placed under house arrest. Hawking, born on the 300th anniversary of Galileo’s death, did not want to share Galileo’s fate. However, in other parts of A Brief History of Time, Hawking demonstrates humility, acknowledging that even if we find a theory of everything and understand why we and the universe exist, this ultimate victory of human reason would merely reveal “the mind of God.” However, this victory has a limitation: the laws we know only hold within the bounds set by the uncertainty principle.
Scientist Hawking sought to pursue the age-old philosophical dream of using reason to uncover the ultimate truths of the universe. His vision of the ultimate victory of human reason is, in essence, a response to a theological question: does the Creator exist, or does the universe require a Creator? Whether or not Hawking succeeded scientifically, he still failed to provide a definitive answer to this question.
It is worth noting that Hawking’s interest in these grand themes may have stemmed from his family background. His father, Frank Hawking, was a medical student at Oxford University and enjoyed debating theology, often telling him Bible stories and indulging in theological studies. His mother, Isobel Hawking, was a graduate of Oxford University’s PPE (Philosophy, Politics, and Economics) program.
As a child, Hawking’s academic performance was poor—he was third from the bottom of his class in first grade. Yet, he did not care and admired himself, focusing more on what intrigued him. Young Hawking was particularly focused on his interests; his mother recalled that once when he was studying the structure of farm machinery parts, other children climbed on his head, but he didn’t even notice.
Due to a tracheotomy, Hawking lost the ability to speak. Because of ALS, he was confined to a wheelchair. Compared to ordinary people, the pleasure his body brought him was almost negligible. Through reading and understanding Hawking, I’ve come to deeply appreciate why Socrates refused his students’ request to help him escape from prison. The students only saw that the Athenian prison had confined Socrates’ body, but Socrates saw that his body confined his soul. We have long focused on how Hawking’s active and profound thoughts were confined in a wheelchair and a physical body—a mixture that seemed insignificant and even odd. As a great theoretical physicist, this was Hawking’s misfortune. He could no longer engage in the complex, delicate, and lengthy mathematical calculations; but it was also his fortune, as he was forced to speak quickly and intermittently like a child, to “compress” his thoughts and focus on grander themes: the fate of the entire universe, and the hopes of all mankind.
In an article commemorating Einstein, Hawking wrote that the world had experienced unprecedented changes over the past 100 years, and the reasons for these changes lay more in science than in politics or economics. The scientific progress of the 20th century is best represented by Einstein. Einstein’s general relativity equations would last as long as the universe. This was a distant echo of Einstein’s refusal to accept the presidency of Israel: politics is temporary, but equations are eternal. As a philosophy teacher, I understand that the great minds of natural science are more concerned with the universe. But here, I want to gently remind readers: we cannot be eternal; we live only in the present. Once we realize this, we will cherish even more the comprehensive explanation of the creation and end of the universe in A Brief History of Time. Even if real time is truly just a figment, we still live in this imagined world. We are beings within time. We love the fragments of space and time around us and also love the efforts of great scientists like Hawking to piece these fragments into a whole.
Reading A Brief History of Time helps us understand time.
A person attempting to understand time is like a drop of water trembling as it melts into the sea.