It is well known that Einstein founded twentieth-century physics with his work on relativity and quanta, but what do we really know about these ground breaking ideas? How were they discovered? What should we retain today from the conceptual upheavals he initiated? Through a selection of concrete scenes taken from Einstein's life, the author offers

Once Upon a Time . . ., Acknowledgments, 1 The Question of Time, 2 The World's Checkerboard, 3 Elastic Space-Time, 4 Einstein's World-Game, 5 Light and Energy in Grains, 6 Confronting the Sphinx, 7 Einstein's Legacy, Notes, Select Bibliography