N. David Mermin is Horace White Professor of Physics Emeritus at Cornell University. He is known throughout the scientific world as co-author of Solid State Physics, and for his columns in Physics Today. He was awarded the Julius Edgar Lilienfeld Prize of the American Physical Society for 'outstanding contributions to physics' in 1989, and is a member of the American Philosophical Society, the US National Academy of Sciences and the American Academy of Arts and Sciences.