We live in a virtual world, a computer-simulated environment. Virtual worlds, such as computer games, can have numerous users who create personalised avatars, engage in activities, and interact with others. If you are familiar with computer games, you know what an avatar is. Once you enter a game, you become a character inside that game, your avatar, and you have an existence apart from your regular life. Inside the game, you are your avatar, not yourself. Alternatively, you could start a virtual world where you are God and make your dreams come true. In this world, you can also become someone else, a character in your story.

Virtual worlds have rules that may draw from reality or fantasy worlds. Rules can include gravity, methods of procreation, and types of communication. In virtual reality, you can change the rules. You can do away with planets and stars and create a flat surface. Or there is no surface at all. You can eliminate gravity and let everyone float. You can do away with procreation and let individuals emerge from thin air. You can invent species that communicate via light signals or not have species but individuals with random features.

This world might look like the original. Our experiences shape our imagination and influence the options we consider. If we write stories and produce films, most are about humans and their feelings and actions. Only a few are about animals. And the animals we imagine in our tales are like humans. Ed, the talking horse, is more human than a horse. Tales and motion pictures about imaginary beings, such as The Lord of the Rings or the Star Trek series, are rare compared to series about humans. And the fictitious beings in our stories, such as Star Trek, look and act like humans. They usually have two legs and two arms and walk upright. Extraterrestrials in Star Trek feature males and females.

The Holodeck is a virtual reality room available in the Starship Enterprise in Star Trek. Using holograms, it creates a realistic, interactive simulation of the physical world. On the Holodeck, you can make a personalised environment with objects and people, interact with them, or write a story and play a role in it. With the help of artificial intelligence, we might soon create simulations of humans and the world. If the technology becomes cheap, we could make billions of virtual universes. If we do that, it likely happened long ago, and we live inside a virtual world ourselves.¹

We are about to do so, so this world is probably a simulation. But can we find out? Most philosophers and scientists think we can’t. They have overlooked the obvious. There is an elephant in the room: the things science can’t explain. It begins with establishing that these phenomena aren’t subjective, so there must be multiple credible witnesses or verifiable evidence. Then, you need to certify that it is not due to randomness or a natural phenomenon. To say that the simulation causes these phenomena upends the knowledge we currently believe we have. And so, we must be thorough. Answering the question begins with investigating what we can or cannot know. That is the domain of knowledge theory, a branch of philosophy which deals with the nature of knowledge.

Latest revision: 18 July 2025

1. Are You Living In a Computer Simulation? Nick Bostrom (2003). Philosophical Quarterly (2003) Vol. 53, No. 211, pp. 243-255.