(Photo by EstudioBLAU)

Many people have noticed that there seem to be no new arguments for the truth of any of the world's religions. I recently stumbled upon one, however, and it has given me a moment's pause.

The Oxford philosopher Nick Bostrom has argued that our entire cosmos could be running as a simulation on a supercomputer of the future. This, needless to say, is a bizarre claim, but it can be defended with a few surprisingly plausible assumptions:

Bostrom's first premise is that human consciousness is the product of information processing in the brain. If this is correct, there is probably nothing magical about having the wet stuff of neurons doing the work, and it should be possible to instantiate minds like our own on a computer. Human consciousness, therefore, would be platform independent.

There are smart people who will leap off this train before it leaves the station—the mathematical physicist Roger Penrose thinks that consciousness cannot be the result of mere computation; the philosopher John Searle and the computer scientist David Gelernter believe that consciousness is a matter of computation, but there must be something special about biological neurons.  However, these appear to be minority opinions in the scientific community. The assumption that minds like our own could, in principle, be realized on a computer seems to be on reasonably firm ground.

Bostrom's second assumption is that if we survive the next few centuries without annihilating ourselves, it is just a matter of time before we build computers capable of running virtual worlds populated by virtual people. Our descendants will likely do this, the way we create video games like The Sims. They might create virtual worlds where simulated ancestors live in circumstances very much like our own. In his paper, Bostrom justifies this assumption using known principles of computation and without assuming any breakthroughs in physics.