As Harrison's interest in Indian modes and melodies intensified prior to sessions for Revolver in 1966, he began using the organ as his primary compositional instrument. Songs like "Within You Without You," "Blue Jay Way" and "The Inner Light" all show hallmarks of this approach, with baroque bass passages and sustained chordal structures. "Circles" is among the last of these of these types of songs before Harrison returned the guitar, mostly out of necessity, during his time in India.
Though the track stands out as one of the few Esher demos the Beatles never recorded as a unit (it would surface on Harrison's 1982 solo album Gone Troppo), it's difficult to ignore the fact that it is an exceptionally dreary affair. Dissimilar from the lively acoustic numbers found elsewhere on the tape, "Circles" utilizes what Richie Unterberger evocatively describes as "an eerie organ that seems to have been dragged out of a dusty, disused church closet." Harrison taped two tracks on the instrument – likely a harmonium – sketching a sparse, almost ghostly arrangement. The mood isn't brightened by the solemn lyrics, which find Harrison contemplating the cyclical nature of humanity and the Hindi concept of reincarnation in a voice that barely raises above a whisper. He quotes the ancient Chinese philosopher Lao-Tze, whose teachings also inspired "The Inner Light," suggesting that the pair of songs were written around the same period in late 1967.
It's not known for certain why the Beatles decided to leave the track off the White Album. It's possible that "Circles" was deemed too similar to another sleepy-toned, organ-centric Harrison piece, "Long, Long, Long," which was far more developed.
Or maybe the band's primary songwriters were simply unwilling to cede too much album real estate to their lead guitarist.