"What the Dead Men Say" is a science fiction novella by American writer Philip K. Dick, first published in Worlds of Tomorrow magazine in June 1964. The manuscript, originally titled "Man With a Broken Match", was received by Dick's agent on 15 April 1963.The concept of "half-life" introduced in the story was used again and developed in Dick's 1969 novel Ubik, which even re-uses a page of the novella verbatim. Source: Wikipedia (en)