Why should the US invest in brain science? See David's opinion in the New York Times.
Hear the actress Emily Blunt (Young Victoria, Devil Wears Prada) read "The Cast" from Sum. She is one of the dozens of terrific actors who read for the audio book.
In September, 2009, Sum became the number 2 book in the United Kingdom on Amazon's bestseller list, only behind Dan Brown's Lost Symbol.