The Marriage of Heaven and Hell "A Memorable Fancy" plate 14 (1790 - 1793). Inspired the title of Aldous Huxley's 1954 book about drug experimentation, The Doors of Perception, which in turn inspired the name of the 1960s rock group The Doors.
Albert Einstein (2015). “Bite-Size Einstein: Quotations on Just About Everything from the Greatest Mind of the Twentieth Century”, p.24, St. Martin's Press