" Complexity is self-generating. The diversity of our world is understandable because it is possible to design imaginary self-consistent worlds potentially as complex as our own.     This is no mere restatement of common sense. Everyone daydreams alternate worlds, but the imagination soon tires of filling in details. Ulam, Von Neumann, and Conway showed that a few recursive rules can paint in all the details. Creation can be simple. "

― William Poundstone , The Recursive Universe: Cosmic Complexity and the Limits of Scientific Knowledge