This work was created from the statement But, all you have to do is make the robot recognize its surroundings. Salamanders do it, and how complex are they? Little did we know what a long path was started with those simple words. This book is a small step on that path, which we hope leads to robots that can serve as true and useful assistants to humans. At the least, we hope for some help with the tasks that are described by the 3 d**** words (dull, dirty, or dangerous). Fair warning, this work is a synthesis of ideas from many disciplines. As such, we have depended on the work of many other researchers and philosophers. The heart of this work, the lens model, comes from the work of Egon Brunswik. Even though he died in the 1950s, his ideas are still strong enough to resonate into the 2000s and into our robot. Another researcher whos work has greatly in?uenced this work is Walter Freeman, Professor Emeritus of Neurobiology at the University of California, Berkeley. We have relied heavily on his work on preafference and attention to guide the development of our robot. In addition, we have used research from a myriad of different ?elds. Our huge thanks to all the researchers whos work we used to synthesize this new theory. Denver, CO Louise F. Gunderson July 2008 James P.