sentences:  Science Fiction writer Ray Nelson's 1975 novel "Blake's Progress" is based on the assumption that Blake was a time-traveler, possessing the ability to travel to the past or future, and that many of Blake's "visions" - sometimes conceived as indications of his "madness" - were actual, concrete things he had seen in these past and future times that he visited.The 2017 Robert Langdon series' best selling mystery-thriller novel "Origin", written by American author Dan Brown, incorporates text from the Blake poem "Vala, or The Four Zoas" as a prominent plot point of the story.Blake was particularly influential on the young generation of early twentieth-century English landscape painters, such as Paul Nash and Dora Carrington.