Nearly all of his forty-four published books were science fiction, but Philip K. Dick, who died in 1982, has influenced countless writers and filmmakers with sociological, political, and metaphysical themes that trenscend genre. The Exegesis of Philip K. Dick, edited and introduced by Pamela Jackson and Jonathan Lethem, forthcoming from Houghton Mifflin Harcourt this fall, is the author's final work.