Inventor and visionary computer scientist Ray Kurzweil probes the past, present, and future of artificial intelligence, from its earliest philosophical and mathematical roots to tantalizing glimpses of 21st-century machines with superior intelligence and truly prodigious speed and memory. Generously illustrated and easily accessible to the nonspecialist, this book provides the background needed for a full understanding of the enormous scientific potential represented by intelligent machines as well as their equally profound philosophic, economic, and social implications.