Our ignorance of the cosmos is too vast to commit to atheism, and yet we know too much to commit to a particular religion. A third position, agnosticism, is often an uninteresting stance in which a person simply questions whether his traditional religious story is true or not true. I call myself a possibilian. Find out why.
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.
Read David's new article in Wired magazine: "Apocalyse? No. Six Ways the Internet Will Save Civilization"
Sum was the only book of fiction in New Scientist magazine's selection of Best Books of 2009.