"Mind Games" is the title track from an album of the same name by John Lennon. It was also released as a single, reaching 26 in the UK Single Charts and #18 on the U.S. Billboard Hot 100, the B-Side was Meat City. Originally titled "Make Love Not War," the song evoked lingering hippie sentiments mixed with the evolving mysticism of the early 1970s.[citation needed] Although Phil Spector was not involved in this album, Lennon's production is similar to the Spector "Wall of Sound." This song, which was begun in 1969 and can be heard in the Beatles' Let It Be sessions, was inspired by the book of the same name by Robert Masters and Jean Houston (1972), which emphasized the power of the human brain to induce various states of consciousness without the aid of external substances. The book presented a series of exercises intended to maximize one's potential for problem solving, conflict resolution, visionary thinking, creativity, focused listening and super-communication. Each application would start with a brief meditation cycle followed by the guided instructions of a director. During the exercise, only the director would speak, but each person would share their experience afterwards. Mind alteration had long since been a point of interest to Lennon, however he was aware of the risks involved with chemical consumption. A recommendation by Lennon himself is included with the book.