There&#x27;s a school of thought that says we&#x27;re already in a virtual reality.<p>As I understand it, the argument is basically that, assuming true high-fidelity virtual reality is possible, then it&#x27;s likely that any society that advances far enough technologically will eventually create a virtual world and populate it (or let it populate itself) with virtual beings that don&#x27;t know they&#x27;re in a virtual reality. Given this assumption, if you let the virtual reality run long enough, then the virtual beings inside the virtual reality will eventually end up creating yet another layer of virtual reality. Assuming this is possible at all, it then follows that there could be an effectively infinite number of virtual realities layered inside each other, and under those circumstances, it&#x27;s extremely unlikely that our reality happens to be the outermost &quot;real&quot; reality but is instead somewhere in the stack of virtual realities.