Keith Devlin is the Dean of the School of Social Science at St. Mary's College, Moraga, California, and a Senior Researcher at the Center for the Study of Language and Information at Stanford University. He is the author of 22 books, one interactive CD-ROM, and over 65 technical research papers in mathematics. His voice is heard regularly on National Public Radio, on such programs as "Weekend Edition," "Talk of the Nation," "Science Friday," "Sounds Like Science," and "To the Best of Our Knowledge." His previous books include Life by the Numbers, the companion to a PBS series that aired in April and May, 1998; Goodbye Descartes: The End of Logic; and The Language of Mathematics: Making the Invisible Visible.