Mathematician Stephan Wolfram has recently proposed that many different kinds of complex systems, including human thought and action, can be modeled using cellular automata. These very simple computational systems have demonstrated that they are capable of generating complex patterns using simple rules. According to physicist Ed Fredkin, cellular automata underlie physical reality on a subatomic level; in his view, nature itself is software running on a Universal Computer. This presentation will look critically at these claims, asking whether we should consider them as physical models or as over-determined metaphors that would inevitably emerge in a historical period when computation is pervasive. This issue, and its proliferating implications, will be explored through Greg Egan’s print novel Permutation City, which imagines a world in which it is possible to simulate a person’s consciousness inside a computer, creating a Copy that has all the personality and memories of the original.