What lies outside virtual reality ?

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Heading away, in Second Life. (Image copyright 2003, Linden Research, Inc. All Rights Reserved.)

Portable simulation machine at Oxford

What is outside of a virtual world? Such a world is not created by subdividing some physical space. There is no larger continuum that is the source of a virtual world. So what's outside?

  1. Strictly speaking a virtual world has no outside. The old Greek argument applies here: if there were an edge or border and you went there and threw a spear, and it moved, then there would be something outside -- which in this case would be another part of the virtual world.
  2. Or a virtual world could be finite and bounded, you could come to an edge and go no farther, or it could have a topology that returned you to where you started, as when one walks around the globe.
  3. In another sense, outside the virtual world are other virtual places that it might be linked to, but these links don't traverse physical space. When two virtual worlds have no internal links, then there is no "spatial" relation between them.
  4. In still another sense, outside the virtual world we find the usual physical world, with its causal interactions that are maintaining the virtual world. But that inside/outside relation differs from the relation between the inside and outside of a house. It is more like relation between a dream and waking life.