Below The Beltway

That’s what one computer scientist seems to think:

Until I talked to Nick Bostrom, a philosopher at Oxford University, it never occurred to me that our universe might be somebody else’s hobby. I hadn’t imagined that the omniscient, omnipotent creator of the heavens and earth could be an advanced version of a guy who spends his weekends building model railroads or overseeing video-game worlds like the Sims.

But now it seems quite possible. In fact, if you accept a pretty reasonable assumption of Dr. Bostrom’s, it is almost a mathematical certainty that we are living in someone else’s computer simulation.

This simulation would be similar to the one in “The Matrix,” in which most humans don’t realize that their lives and their world are just illusions created in their brains while their bodies are suspended in vats of liquid. But in Dr. Bostrom’s notion of reality, you wouldn’t even have a body made of flesh. Your brain would exist only as a network of computer circuits.

You couldn’t, as in “The Matrix,” unplug your brain and escape from your vat to see the physical world. You couldn’t see through the illusion except by using the sort of logic employed by Dr. Bostrom, the director of the Future of Humanity Institute at Oxford.

Dr. Bostrom assumes that technological advances could produce a computer with more processing power than all the brains in the world, and that advanced humans, or “posthumans,” could run “ancestor simulations” of their evolutionary history by creating virtual worlds inhabited by virtual people with fully developed virtual nervous systems.

Some computer experts have projected, based on trends in processing power, that we will have such a computer by the middle of this century, but it doesn’t matter for Dr. Bostrom’s argument whether it takes 50 years or 5 million years. If civilization survived long enough to reach that stage, and if the posthumans were to run lots of simulations for research purposes or entertainment, then the number of virtual ancestors they created would be vastly greater than the number of real ancestors.

It’s a fascinating concept to think about, but does it really matter whether its true or not ?

A more practical question is how to behave in a computer simulation. Your first impulse might be to say nothing matters anymore because nothing’s real. But just because your neural circuits are made of silicon (or whatever posthumans would use in their computers) instead of carbon doesn’t mean your feelings are any less real.

David J. Chalmers, a philosopher at the Australian National University, says Dr. Bostrom’s simulation hypothesis isn’t a cause for skepticism, but simply a different metaphysical explanation of our world. Whatever you’re touching now — a sheet of paper, a keyboard, a coffee mug — is real to you even if it’s created on a computer circuit rather than fashioned out of wood, plastic or clay.

You still have the desire to live as long as you can in this virtual world — and in any simulated afterlife that the designer of this world might bestow on you. Maybe that means following traditional moral principles, if you think the posthuman designer shares those morals and would reward you for being a good person.

Or maybe it just means living your life and not worrying about the ramblings of philosophers.