Rob,
.999 repeating is exactly equal to 1.
Johan,
The philosopher Daniel Dennett argues that we can't be simulated in a computer because computers aren't fast enough to do stuff. Dennett's argument is wrong, because we don't know how fast putative REAL computers might be.
Your philosopher is also wrong, though. Math and logic exist prior to programming. If we follow the analogy it means that the programmers in the putative REAL world must have some mathematics. Following the logic, we must believe that THAT world was a virtual reality.
While I don't have a theoretical problem with recursion (it being one of my fortes), I do think that this is an argument leading nowhere - someone akin to the "Am I a man dreaming he is a butterfly or a butterly dreaming he is a man?" type question.
