"Comfortably Numb" (working title "The Doctor") is a song by the English rock band Pink Floyd, which first appears on the 1979 double album The Wall. It was also released as a single in 1980 with "Hey You" as the B-side. It is one of only three songs on the album for which writing credits are shared between guitarist David Gilmour and bassist Roger Waters. The chorus music and guitar solos were written by Gilmour while Waters contributed the lyrics and the music for the verses. An early version of the song was included under the working title on the "Immersion Box Set" of The Wall, released in 2012.

The song is one of Pink Floyd's most famous, and is renowned especially for its guitar solos in the middle and at the end of the song. In 2004, the song was ranked number 314 on Rolling Stone magazine's list of the 500 Greatest Songs of All Time. In 2005, it became the last song ever to be performed by Waters, Gilmour, keyboardist Richard Wright, and drummer Nick Mason together. In 2011, the song was ranked 5th in the BBC Radio 4's listeners' Desert Island Discs choices. The two guitar solos were ranked as the greatest guitar solos of all time by both Planet Rock listeners and WatchMojo.com.

While most songs on The Wall were written by Waters alone, most of the music for "Comfortably Numb" was written by David Gilmour, who originally recorded the instrumental demo during the latter stages of recording his first solo album, hoping to find some later use for it. Gilmour later brought his demo of it to The Wall sessions. In Gilmour's original demo, though there were no lyrics, he sang a melody not unlike the final version of the chorus. The verses, however, were in the key of E minor (a progression of E minor, D major, C major, A minor, and back to E minor again), rather than B minor, as in the final version. Also, the chord sequence for the final chorus line "I have become comfortably numb" did not exist in Gilmour's demo. So, while the music is widely considered to be Gilmour's work, it is likely that Waters composed the chords for that line, as well as making the decision to change the verses from E minor to B minor.

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