The only thing missing is most of the knowledge we'll need to make such machines intelligent. Indeed, as you might guess from all this, the focus of research in Artificial Intelligence should be to find good ways, as Vinge's fantasy suggests, to connect structures with functions through the use of symbols. When, if ever, will that get done? Never say "Never".

VERNOR VINGE

A Hugo and Nebula Award finalist for True Names, he is also the author of The Peace War, Grimm's World, and a number of short stories. A mathematician and computer scientist, he has published articles in magazines such as Omni. He teaches at San Diego State University.

BOB WALTERS

His illustrations have graced the pages of SF magazines such as Analog and Isaac Asimov's SF Magazine. He has also done a great deal of scientific illustration for college texts, as well as general advertising illustration. He lives in Philadelphia, Pennsylvania.

MARVIN MINSKY

Considered by many to be the father of Artificial Intelligence, he has written especially for this book an essay on the nature of intelligence, natural and artificial. He is the director of the Artificial Intelligence laboratory at the Massachusetts Institute of Technology.