John Lennon wrote this, and described it as "my first psychedelic song." It was inspired by Timothy Leary and Richard Alpert's book The Psychedelic Experience: A Manual Based On The Tibetan Book Of The Dead
, which Lennon discovered at Indica Books and Gallery (inspiration for "Paperback Writer
The book is a reinterpretation of the Tibetan Book of the Dead
and a guide to understanding it through psychedelic drugs. Lennon would read it while tripping on LSD, and according to his biographer Albert Goldman, he recorded himself reading from the book, played it back while tripping on LSD, and wrote the song.
The most overt reference to the book is the line:Turn off your mind
Relax and float downstream
It is not dying
The book states: "Whenever in doubt, turn off your mind, relax, float downstream."