we have something within their own literature stating otherwise?
"Apocalypse, or Revelation, is the name of the last book in the Bible, written toward the end of the first century C.E. In view of the prophetic nature and highly SYMBOLIC language of this book, the adjective “apocalyptic” came to be applied to a form of literature that began long before the Bible book of Revelation was written. The mythological SYMBOLISM of this literature goes back to ancient Persia and even beyond."
Watchtower Magazine 12/1/1999 page 4 : )