Douglas Hofstadter is a professor of Cognitive Science and Comparative Literature at Indiana University in Bloomington. His research into cognitive science includes concepts such as the sense of self in relation to the external world, consciousness, artistic creation, literary translation, and discovery in mathematics and physics. His 1979 book Gödel, Escher, Bach: An Eternal Golden Braid won both the Pulitzer Prize for general nonfiction. His AI interests explore the subtlest and most slippery aspects of human intelligence, as embodied in deceptively deep analogy problems like ABC is to ABD as XYZ is to what?