Is our world virtual? This question may sound like something straight out of a science fiction novel, but it actually touches on the profound core of both philosophy and science. From ancient times to the present, humanity has never ceased to question what is “real.” And when we attempt to answer whether this world could be virtual, we inevitably have to return to classic thought experiments and theoretical foundations to search for clues.

Let’s begin with Descartes. This 17th-century philosopher laid the foundation for modern philosophy with a simple yet profound statement: “I think, therefore I am.” At first glance, this seems like just an affirmation of self-existence, but behind it lies a deep spirit of doubt: if we cannot even be certain that we ourselves exist, how can we trust everything we perceive? Descartes proposed an extreme possibility, known as the “evil demon hypothesis”: perhaps an all-powerful evil force is manipulating our senses, making everything we experience nothing but an illusion. In other words, everything we see, hear, and touch, even our own bodies, could be a carefully crafted deception. While this skeptical view is unsettling, it forces us to reconsider what is “real.” If we cannot verify the reality of the external world through our senses, what can we rely on as a trustworthy basis?

Next, let’s turn to Plato’s Allegory of the Cave. In this famous metaphor, Plato depicts a group of people chained inside a cave, facing a wall, watching shadows cast by a fire behind them. To them, these shadows are their entire reality, as they have never seen the actual objects or the light source. It is only when one of them escapes the chains and steps out of the cave that he sees the real world bathed in sunlight for the first time. However, when he returns to tell the others the truth, he is ridiculed and even attacked because his description exceeds their limited understanding. This story not only reveals the limitations of human cognition, but it also hints at a deeper question: could we, like the prisoners in the cave, be living in a lower-dimensional projection, with true reality existing in a higher-dimensional space? If so, then perhaps “virtual” does not refer to a computer-generated simulation, but rather to the idea that our current experiences and cognitive abilities are insufficient to access ultimate truth.

Of course, when discussing the nature of the world, we must address the debate between idealism and materialism. These two philosophical positions represent entirely different worldviews. Idealists argue that consciousness is the fundamental basis of the universe, and the material world is merely a product of consciousness. In other words, without an observer, there is no objectively existing world. For example, Bishop Berkeley once said, “To be is to be perceived,” a statement that may seem absurd at first, but upon closer inspection, it challenges our belief in “objective reality independent of consciousness.” If you close your eyes and then open them again, how can you prove that the scene you just saw still exists? If there is no continuous observer, will the world instantly disappear? These questions may seem abstract, but they strike at the heart of our understanding of reality.

On the other hand, materialists maintain that matter is primary, and consciousness is merely the result of complex material systems, like the brain, at work. From this perspective, even if humans or other intelligent life forms did not exist, the Earth, solar system, and even the entire universe would still operate according to physical laws. This explanation clearly aligns with scientific knowledge, but it also presents some thorny issues. For example, since our senses and thoughts are made up of matter, can they truly and fully reflect the real nature of the external world? After all, the human eye can only capture a limited range of wavelengths of light, and the ear can only hear a certain range of frequencies. This means that our perception of the world is inherently limited. Further, if our brains are just machines processing information, might they, like computer programs, only present filtered and processed data, rather than the complete and unaltered “truth”?

Interestingly, with the advancement of technology, especially in the fields of artificial intelligence, quantum mechanics, and brain science, these philosophical issues have once again gained new relevance. For example, the double-slit interference experiment in quantum mechanics shows that the behavior of particles can be influenced by how they are observed, as if they “know” they are being “watched.” This discovery brings to mind the idealist perspective: perhaps the observer’s consciousness does play a role in constructing reality. Additionally, advances in virtual reality technology have prompted people to reconsider: if, one day, we could create a sufficiently realistic digital world in which humans living within it could not distinguish between the virtual and the real, could such a world still be called “false”? Or, where exactly is the boundary between the virtual and the real?

Returning to the question at the beginning: is our world virtual? The answer may not be as important as we think, because whether the world is real or virtual, we still face the same challenge: how to better understand it, adapt to it, and give it meaning. As the philosopher Kant said, what matters is not what the world is like, but how we perceive it. Perhaps we may never know the ultimate answer, but that does not stop us from continuing our exploration. After all, it is this unceasing curiosity that defines what it means to be human.

Is our world virtual? This question may sound like a plot twist from a science fiction novel, but it has sparked profound discussions in physics and cosmology. From quantum mechanics to the multiverse hypothesis, and to information physicalism, scientists are using rigorous theoretical tools to explore what seems like an absurd question: could the reality we perceive be nothing more than some sort of “simulation” or “construct”? Let us dive into these fascinating thought experiments to see how they challenge our understanding of the world.

We cannot discuss this without mentioning the observer effect and wave function collapse in quantum mechanics. If you are familiar with quantum mechanics, you have likely heard of Schrödinger’s cat, a thought experiment that reveals a puzzling fact: at the microscopic level, a particle’s state is not definite, but exists in a probabilistic form until it is observed, at which point it “chooses” a specific state. In other words, before being observed, an electron can exist in multiple positions simultaneously; but once measured, its wave function collapses into a definite position. This phenomenon raises the question: could the physical world itself depend on the act of “observation”? If so, does that mean what we call “reality” is a phenomenon that requires consciousness to participate in its existence? Further, if our entire universe follows similar rules, does that mean everything we experience is the result of a “program” generated by some higher-dimensional system? Of course, this is just a philosophical conjecture, but it certainly raises new questions about the nature of matter—perhaps matter is not as solid and reliable as we once thought, but rather a dynamic manifestation based on information.

Another mind-boggling concept is the multiverse hypothesis. According to some modern physical theories, such as string theory or inflation theory, our universe may not be the only one. Instead, there could be countless parallel universes, each with its own unique physical laws, initial conditions, and even historical trajectories. If this hypothesis is true, then the world we inhabit is just one of many possibilities. Imagine that when you wake up in the morning and decide whether to wear a blue shirt or a red one, your choice might lead to two different universes branching out: in one universe, you wear the blue shirt to work; in the other, you choose the red one. Though these parallel universes operate independently and cannot communicate, their existence suggests a larger picture: what we perceive as “reality” may just be a small node in the vast multiverse network. If we think of the entire universe as a giant movie, the scene we each experience is just one frame. In this sense, the concept of “virtual” seems closer: if infinite possibilities exist, and we can only experience one version, does this mean our reality has some sort of “filtering mechanism,” much like a computer program generating specific scenes?

Let’s also discuss information physicalism, an increasingly popular field in recent years. Traditional physics tends to view the universe as an entity composed of fundamental particles, but information physicalism proposes a radically different view: the core of the universe is not matter, but information. Simply put, all physical phenomena can be reduced to the process of information processing. For example, studies of black holes show that the amount of information stored on a black hole’s surface is proportional to its area, not its volume, known as the “holographic principle.” This discovery challenges our traditional understanding of three-dimensional space, suggesting that the entire universe might operate like a projection on a two-dimensional screen. If the universe is made of information, then the line between it and virtual reality becomes blurred. After all, whether in a computer game or artificial intelligence, the foundation is code and data flow. If the universe itself is a complex information system, then we, as part of it, might be like game characters, following predefined rules. This thought may be unsettling, but it is also poetic: we may each be a note in the grand symphony of the universe, collectively composing a movement about existence.

Of course, these theories are still hypothetical and have not been fully proven. But it is these bold speculations that push science forward. They remind us not to accept reality at face value, but to keep our curiosity alive and continue questioning the fundamental issues hidden beneath the surface. Returning to the question at the beginning: is our world virtual? The answer may not matter much, because what is truly important is that, in this process, we learn to better understand ourselves and the universe. Even if we eventually prove that we live in a “real” world, the journey of thought itself will have been fascinating.

When discussing whether “our world is virtual,” computer science and technology offer us many thought-provoking angles. From the simulation hypothesis to digital cosmology, to the discussion of artificial intelligence and consciousness, these concepts not only challenge our perception of reality but also make us rethink our position in this universe.

Let’s talk about the Simulation Hypothesis. This theory was first proposed by philosopher Nick Bostrom, who argues that humanity might be living in a simulated world created by an advanced civilization. Imagine that, one day in the future, technology advances to the point where it can fully replicate every detail of the real world—including physical laws, social interactions, and even individual emotional experiences. Would such a simulation be indistinguishable from reality? Furthermore, if we cannot distinguish between what is “real,” how can we prove that everything we are experiencing is not the result of a supercomputer running a simulation? This may sound like a plot from The Matrix, but it has deep logical support. Modern computers are already able to generate realistic virtual environments through complex algorithms, and cutting-edge technologies like quantum computing and neural networks are rapidly pushing the boundaries of this capability. Therefore, some speculate that in a few hundred years, humanity might create a virtual world even more complex and realistic than today’s, and we might be part of that experiment. Of course, this raises an interesting question: if the simulation exists, who is controlling it? Is it an advanced civilization, or some entity beyond our understanding?

We can also turn to Digital Cosmology, another way of viewing the nature of reality. Digital Cosmology suggests that our world might essentially be a massive digital simulation. In other words, the entire universe operates like a giant computer, where all matter, energy, and even time itself can be seen as composed of basic code or data. This may sound absurd, but it actually aligns with some findings in physics. For example, in quantum mechanics, scientists have found that the behavior of microscopic particles often exhibits discreteness rather than continuity. This discreteness resembles the “0” and “1” in binary code. Furthermore, research in information theory has shown that any system can be described in terms of information, and the process of information processing is akin to computation. Based on this, some scholars have proposed a bold hypothesis: perhaps our universe is not made of traditional matter, but of information, with these pieces of information following an extremely complex set of rules for computation. If this is true, then what we call “reality” is not what we see with our eyes, but rather a series of intertwined data flows.

Finally, the most exciting and controversial topic is the relationship between artificial intelligence and consciousness. In recent years, with the rapid development of AI technology, more and more research has focused on whether machines can possess self-awareness. Although there is no definitive evidence that AI has true subjective experience yet, they have made astonishing progress in mimicking human thought. For example, language models like GPT-4 can generate fluent text that even seems to express emotions; AlphaGo’s victory over Go champion Lee Sedol demonstrated strategic intelligence that amazed many. However, as AI approaches human-level intelligence, an inevitable question arises: if, one day, AI truly gains self-awareness, can we still insist that our “reality” is unique? After all, if consciousness can be encoded into algorithms and embedded into machines, does that mean our own consciousness could also be the result of an advanced algorithm? In other words, could we just be a program within some larger system, mistaking ourselves for free, independent beings because we lack the proper perspective?

To better understand this, let’s do a thought experiment. Suppose you are a programmer designing a highly intelligent game character. To make this character seem real enough, you give it memory, learning abilities, and a certain degree of autonomy. Over time, this character becomes more complex, even beginning to question its own existence and seeking answers. For it, the world within the game is its entire reality because it lacks the ability to step outside the frame and observe the real world. As the creator, would you tell it the truth? More importantly, if you choose to hide it, how could it ever know it is living in a virtual world? Expanding this metaphor to the entire universe, could we also be similar characters, trapped in some grand simulation, unable to find the exit?

Of course, the above viewpoints are not without controversy. Critics point out that even if we could build highly realistic virtual worlds, it does not necessarily follow that we are living within one. After all, science is about empirical evidence, not mere speculation. Furthermore, even if the universe could be represented digitally, it does not mean it is an artificially created product; perhaps this is just a manifestation of natural laws. Additionally, the discussion about AI consciousness faces numerous challenges. We still do not understand the essence of consciousness, let alone reduce it to mathematical formulas or programming languages. Therefore, while these questions are captivating, there is still a long way to go before we arrive at definitive conclusions.

Nonetheless, the value of such thinking lies in its ability to inspire us to reflect on the meaning of reality. No matter what the final answer is, exploring the question of whether “our world is virtual” helps us broaden our horizons and encourages us to understand life, the universe, and everything from a new perspective. Perhaps the truth does not matter, and what truly matters is what we learn and how we grow during this journey. After all, whether virtual or real, as long as we can feel love, hope, and creativity, the world is already beautiful enough.