The Door to a Simulated World, Just Beyond Our Reach

How far can VR go in fooling us?

October 27, 2026 · Joo-Ho Lee

Prologue: Meta Chooses a Different Path

On October 28, 2021, the global social media company Facebook changed its name to Meta. It was a declaration that the next era of the internet would be one we stepped into, rather than watched on a screen. People would hold meetings in virtual offices, meet friends at virtual concert venues, and shop on virtual streets.

Almost five years have passed. Meta's Reality Labs division, responsible for virtual reality, augmented reality, smart glasses, and related products, recorded an operating loss of about $19.2 billion in 2025 alone. Those losses did not all come from VR headsets. In its 2025 annual report, Meta said it planned to allocate roughly 70 percent of the division's 2026 expenses to wearables, with the remaining 30 percent going to VR and its virtual-world platform, Horizon. The balance of investment is shifting from headsets that cover up reality toward smart glasses people can wear in everyday life.

One of the world's wealthiest companies, with an extraordinary pool of talent, has spent so much money over so many years, yet has not made virtual worlds part of people's daily lives. Of course, there are market challenges too: price, content, and comfort. Is the technology simply not mature enough yet? Or was there a barrier that was difficult to overcome from the start?

I think that barrier lies not only in the machines, but in us. This essay is about what that barrier looks like, and what VR can still do in its presence.

1. A Two-Hundred-Year Dream of an Artificial World

Attempts to create an artificial world go back further than we might think. In 1838, the British physicist Charles Wheatstone demonstrated that showing slightly different pictures to the left and right eyes could make flat images appear three-dimensional. He built a device called a stereoscope. The principle is that the brain interprets the difference between the two eyes' views as depth. Remarkably, today's VR headsets still rely on essentially the same principle: showing each eye a different image.

In 1962, the American cinematographer Morton Heilig received a patent for a machine called the Sensorama. Viewers sat in a chair and looked into a cabinet, where they experienced stereoscopic images and stereo sound. The chair vibrated, air blew across their faces, and scents matched the scene. It was a machine designed to fool the whole body, not just the eyes and ears. But Heilig could not find investors, and the Sensorama never became a commercial success.

In 1968, the American computer scientist Ivan Sutherland and his colleagues presented a computer display worn on the head. When the user turned their head, the computer detected the movement and changed the viewing angle of the shapes on the screen. The device was so heavy that it had to hang from the ceiling, earning it the name “the Sword of Damocles”: a sword suspended overhead. Today's VR headsets are its direct descendants.

In the more than half a century since then, displays have become astonishingly sharp, devices have grown lighter, and prices have fallen. Yet one thing has barely changed. Mainstream VR still concentrates on recreating what we see and hear. More than sixty years after Heilig tried to fool the whole body in 1962 with a vibrating chair, wind, and scents, that experience has yet to find a place in the average living room. There is a reason for that.

2. We Have More Than Five Senses

As children, we learn that human beings have five senses: sight, hearing, touch, taste, and smell. But that is only a convenient shorthand. Our bodies actually take in far more kinds of information at once.

Even as you read these words, the vestibular organs deep inside your ears are measuring which way your head is tilted and which direction your body is accelerating. Sensors in your muscles and tendons let you know where your arms are, even with your eyes closed. Your skin senses heat, cold, and pain. Inside your body, you feel hunger, your heartbeat, and shortness of breath. We are barely conscious of much of this, but when these sensations diverge too far, our bodies may tell us that something is wrong.

Each sense is also more complicated than we tend to imagine. The skin of our fingertips is densely packed with several kinds of receptors, each detecting different things: light touch, vibration, pressure, and the stretching of the skin. We can tell silk from sandpaper because the signals from these receptors work together. Smell is harder still. The human nose has roughly 400 types of receptors that recognize odor molecules, and combinations of their responses allow us to distinguish an enormous range of smells. A display can create a vast array of colors by mixing just red, green, and blue light. No universal equivalent of those three primary colors is known for smell.

Most importantly, these senses do not work in isolation. The brain continually compares what the eyes see, what the ears hear, what the balance organs in the ears detect, and what the ground feels like under our feet. From all of this, it constructs our experience of the world. Our sense of “reality” depends not only on the vividness of any one sensation, but on how well our different senses and past experiences fit together.

3. When the Body Detects the Lie

Quite a few people who have tried a VR headset have felt dizzy or nauseated within minutes. This is especially common when riding a virtual roller coaster or walking through a virtual world with a joystick. What is often called “VR sickness” involves not only the characteristics of the device and its content, but also the way the body processes sensory information.

One leading explanation is sensory conflict. Your eyes say that your body is rushing forward, while the balance organs in your ears and the muscles in your legs say that you are standing still. The two witnesses disagree. The idea that such mismatches can cause sickness is also connected to research on motion sickness in boats and cars. But no single cause explains every case of VR sickness. Display latency, motion, and individual differences also matter.

Even if we consider the eyes alone, problems remain. When we look at something nearby in the real world, our eyes turn inward, and their lenses focus on the nearby object. Those two actions normally work together. In a conventional fixed-focus headset, however, the apparent distance of a virtual object can differ from the optical distance at which the eyes must focus. This mismatch can cause eyestrain and discomfort. Technologies that change the focal distance are being explored, but the ability to adjust focus does not, by itself, make a device comfortable to use for long periods. A gaze-driven system, for example, must track the eyes accurately and respond quickly while keeping the image clear. Its weight and fit must also be manageable. The practical difficulty of a head-mounted display, or HMD, lies in meeting all of these requirements together in a small device.

Here we reach VR's dilemma. A sharp display and vivid sound do not automatically fill the gaps left by the other senses. Your eyes tell you that you are standing at the edge of a cliff, but the soles of your feet feel the living-room floor. Your hand grasps a virtual cup, but there is nothing between your fingers. In some situations, those mismatches break our belief in the virtual world.

Researchers have, of course, tried to fill these gaps one by one. They have developed vibrating gloves, moving floors, scent-emitting devices, and even full-body suits. But each added sense brings weight, cost, and complexity that must also be addressed. There are more signals to keep in sync. When artificial signals are delivered to each sensory organ separately from outside the body, it is difficult to coordinate every sense precisely at the same time. This is the first wall that VR encounters when it tries to fool our senses one by one.

4. The Final Door: Speaking Directly to the Brain

If there are limits to fooling each sensory organ individually, another path is conceivable: bypass the organs and send signals directly to the brain. Neural activity in the brain is involved in everything we see, hear, and feel. If we could reproduce that activity precisely, sensory technologies that go beyond headsets and gloves might become possible. But sensory information is processed across multiple brain regions, not gathered at a single point. Reaching the brain directly would not automatically bring the senses into agreement.

This is not merely science fiction. Beginning in the 1930s, the Canadian neurosurgeon Wilder Penfield applied weak electrical stimulation to the surface of the brain while operating on conscious patients with epilepsy. Depending on where he stimulated, patients reported tingling in a finger, seeing light, and, in some cases, hearing music or recalling scenes from the past. These observations showed that electrical stimulation of the brain could produce sensory experiences even without the corresponding external stimulus.

Technology that sends signals to peripheral nerves, rather than the brain itself, has already changed countless lives. Cochlear implants convert sound into electrical signals and deliver them directly to the auditory nerve. With appropriate rehabilitation, they help many people perceive sounds and understand speech, though they do not reproduce natural hearing exactly. They offer some of the clearest evidence that sensory technology can succeed by speaking directly to the nervous system.

Doors are opening gradually for other senses too. In 2016, researchers at the University of Pittsburgh implanted electrodes in the sensory cortex of a man who had been paralyzed in all four limbs in an accident. When the electrodes were stimulated as someone pressed a finger on a robotic hand, he reported feeling as though his own finger were being touched. In January 2024, Neuralink implanted its device in a human brain for the first time. A participant with paralysis in all four limbs subsequently controlled a computer cursor using signals associated with the intention to move. That was an achievement in reading signals from the brain, not evidence that a complete sensory experience had been written into it.

But we should also look at the other side of these successes. Argus II, an artificial retina for people who had lost their sight, received approval in Europe in 2011 and in the United States in 2013. It had just 60 electrodes, however, and provided limited patterns of light and dark rather than natural vision. Some users could make out the stripes of a crosswalk; others struggled to distinguish even simple shapes. The company stopped production in 2019. As support was subsequently scaled back, some people with implants were left without reliable access to repairs when their devices failed or parts became unavailable.

The human retina contains more than 100 million light-sensitive cells, and the brain has roughly 86 billion neurons. Of course, we cannot compare those numbers with electrode counts on a one-to-one basis. The more important question is which neurons to stimulate, when, and in what patterns to produce the intended experience. Success in producing certain sensations does not mean that we have worked out how to recreate all the senses naturally. We still need to learn whether adding more electrodes would be enough, or whether principles we do not yet understand are also required. Will this door ever open?

5. The Person Standing at the Door

Suppose technology does someday become capable of creating perfectly convincing artificial sensations in the brain. Even then, the door will not open easily. The reason lies not in the machine, but in the person who must accept it. To make VR indistinguishable from reality, we have to convince human senses. And the person whose senses we are addressing is not an object, but someone with a body, desires, and rights.

The body: Would we open our skulls for pleasure?

So far, most people who have had devices implanted directly into their nerves or brains have been patients who could not hear, see, or move, or who were suffering from disease. Surgical risks may be worth taking to regain something that has been lost. But would a healthy person have their skull opened for a more vivid game? There are risks of infection and bleeding, electrodes that may degrade or lose performance inside the body, and the prospect of living with a machine that cannot easily be repaired if its manufacturer withdraws support, as some Argus II patients discovered. A headset can simply be taken off. A device implanted in the brain is not so easily removed.

Desire: What if a perfect illusion becomes addictive?

In 1954, James Olds and Peter Milner at McGill University in Canada implanted electrodes in particular areas of rats' brains. Pressing a lever delivered electrical stimulation to the implanted site. Rats stimulated in some of those areas pressed the lever over and over again. They continued seeking the stimulation even without food as a reward. The experiment showed that stimulation of certain brain regions could itself reinforce behavior.

Recreating sensory experiences is, of course, different from directly stimulating reward circuits. That experiment alone does not establish that perfect VR would necessarily be addictive. Still, we need to ask what risks might arise from virtual worlds designed to keep people inside them. If closing our eyes opened a world more beautiful, more thrilling, and more responsive to our wishes than reality, what would make us want to open them again? Watching how hard we already find it to put down short videos on a screen, I find that question difficult to answer.

Truth: When we open our eyes, are we back in reality?

However vivid today's VR may be, we know it is not real. The headset presses against our nose, and we feel the living-room floor beneath our feet. Paradoxically, that incompleteness protects us. But if every sense were perfectly deceived, how would we tell the artificial from the real? How would the wounds and memories we acquired in a virtual world differ from those acquired in reality? If we could not tell the difference, could we still call it “virtual”?

Power: What if whoever shapes my senses can also read my thoughts?

If a device that sends signals into the brain also gains the ability to read signals from it, ownership of neural data becomes an issue alongside control over our senses. This does not mean that today's technology can read people's thoughts at will. But the possibility of companies collecting and using information derived from brain activity is already a practical concern. Some societies have begun to take it seriously. Chile amended its constitution in 2021 to protect brain activity and the information derived from it amid advances in science and technology. In 2024, the US state of Colorado passed a law protecting data from the brain and nervous system as sensitive personal information. Society, in effect, is putting a lock on the door before the technology has even reached it.

Which path will people choose?

This brings us back to Meta's change of direction. The company is putting new emphasis on glasses that help people find information and communicate in the real world, rather than on headsets that block that world out. This alone does not prove that people have rejected VR. But it does suggest a judgment that there is an opportunity in technology that makes life more convenient while keeping people in reality, rather than taking them away from it. Perhaps this moment asks us to consider not only technological performance, but also people's attachment to the real world.

This, ultimately, is where VR encounters its barriers. The route that fools our senses one by one from outside the body must contend with their complexity. The route that reaches directly into the brain must take account of human bodies, desires, and rights. Whichever route we follow, we meet a human being at the end. Because VR must work with people, advances in technology will not make these limits disappear easily.

6. Give VR a Clear Purpose, and It Becomes a Powerful Tool

None of this means that VR is useless. What I question is the demand that it become a “second reality” from the outset. Once we set aside the goal of fooling every sense and give it tasks for which a few senses are enough, VR is already producing remarkable results.

The oldest example is the flight simulator. In 1929, the American inventor Edwin Link built a device that allowed pilots to practice flying while still on the ground. Today, pilots use simulators to rehearse engine failures, severe weather, and other situations they could not deliberately practice in a real aircraft. A simulator does not need to create a perfect sky. It only needs to represent accurately what the pilot must learn.

The same is true in surgery. In 2002, researchers at Yale University divided 16 surgical residents into two groups and trained only one group in laparoscopic surgery using a VR simulator. They then evaluated a specific stage of an actual gallbladder-removal operation. The VR-trained group made an average of 1.19 errors, as defined in advance by the researchers, compared with 7.38 in the control group. In this small study, errors fell to roughly one-sixth of the control group's level. That number is not a promise of the same effect across all surgery, but it showed that practice in a virtual environment could carry over into performance in a real operating room.

VR is also used to ease pain. At the University of Washington, Hunter Hoffman and David Patterson gave burn patients VR headsets to wear while enduring the severe pain of wound cleaning. The patients threw snowballs at penguins in a snow-covered virtual world called SnowWorld. In some early studies, adding VR to standard pain treatment reduced patients' reported pain by about 35 to 50 percent. The size of the effect varies across studies and patients, but the findings suggest that VR can help support existing treatment. In 2021, the US Food and Drug Administration authorized the marketing of EaseVRx, a prescription VR device designed to help reduce chronic low back pain in adults. Research also continues into treating post-traumatic stress disorder by allowing veterans to confront their memories gradually in virtual combat environments.

These examples have something in common. None tries to deceive people completely. Pilots know they are in a simulator. Doctors know the patients are virtual. Burn patients know the penguins are not real. Yet the benefits remain. What is needed is not a perfect illusion, but enough immersion for the task at hand. Indeed, knowing that “this is not real” can put people at ease and let them practice dangerous tasks safely.

Education, training, rehabilitation, treatment, design, and access to places that are difficult to visit: VR shines when it helps us in the real world, rather than trying to replace it. Within those applications, research into making VR lighter, clearer, and less likely to cause sickness remains thoroughly worthwhile.

Conclusion: Before the Door We Cannot Reach

Looking back from Wheatstone's stereoscope to Meta's headsets, technology has been extraordinarily successful at fooling our eyes and ears. But we do not experience the world through our eyes and ears alone. Balance, the position of our bodies, temperature, smell, and the feel of things beneath our fingertips all matter. The brain brings together the sensations and experiences available to it to construct “reality.” It is difficult to make all of them agree at once by fooling each sensory organ separately. The route that reaches directly into the brain faces a higher wall still: our bodies, desires, and rights.

This is where I arrive. Until we can perfectly deceive all the human senses, complete VR that is indistinguishable from reality will be difficult to achieve. That is not proof that it will remain impossible forever. But neither is it easy to believe that the pace of technological progress alone will carry us past these limits. VR is dealing with human beings, not machines. We can see the door to an artificial world, but the further we reach for it, the further away it seems to move.

Yet being unable to open the door does not mean there is nothing worth doing on this side of it. VR is already a valuable tool for training pilots, reducing surgeons' errors, and easing burn patients' pain. What we need is to be clear about what we want it to do, instead of demanding that it become a second reality. When we acknowledge its limits and give it a defined purpose, VR finds its place.

While writing this essay, I often thought of my excellent colleagues in VR research. They ask when a person begins to accept a virtual space as “real,” which mismatches make people feel sick, and how a single vibration at a fingertip can create an illusion of weight or texture. For each question, they develop hypotheses, design experiments, and carefully record the responses of countless participants.

At first glance, their work is about making better VR. Take a step back, though, and it is also about understanding human beings more deeply. Before we can fool the senses, we have to understand them. At the very points where VR fails to deceive us completely, researchers are uncovering, piece by piece, how intricately our bodies and brains construct the world. Follow the limits of the machine, and eventually you come face to face with the human being. I have genuine admiration for that persistent effort.

Research that expands what VR can do should not stop: lighter equipment, less sickness, more precise touch, and better neural technologies for people who cannot hear or see. Even if we never reach a fully convincing artificial world, the journey toward that door has already given us tools that make reality a little better. Perhaps VR's true value lies not beyond the door, but along the path that leads to it.

Sources and Further Reading

Meta 2025 annual report · Focus conflicts and eye fatigue · Brain stimulation and touch · Bionic eyes without support · Brain stimulation and reward · Chile neurorights law · Colorado neural data law · VR surgical training · VR for burn pain · FDA authorization of EaseVRx