His son's artwork appears to have inspired Lennon to draw heavily on his own childhood affection for Lewis Carroll's "Wool and Water" chapter from Through the Looking-Glass. At least one lyric was influenced by both Carroll and skits on a popular British radio comedy programme (The Goon Show) making references to "plasticine ties", which showed up in the song as "Plasticine porters with looking glass ties". A parody of "Twinkle Twinkle Little Star", recited by the Mad Hatter, appears in Lewis Carroll's Alice's Adventures in Wonderland.
Paul McCartney recounted trading lyric ideas with Lennon in an interview, saying, "We never noticed the LSD initial until it was pointed out later, by which point people didn't believe us."[6] This is confirmed by a 1971 interview of Lennon, where he admitted to curiously going so far as to search for anagrams in his other work, only to find "they didn't spell out anything." George Martin also denied the song was about LSD in the book The Complete Beatles Recording Sessions by Mark Lewisohn. However, Lewisohn goes on to say "there can be little doubt that this was the very substance that provoked such colourful word imagery to flow out of Lennon's head and onto paper." [7] McCartney agrees in a 2004 interview, where he noted that Julian's painting had inspired the song, but that it was "pretty obvious" that the song was also inspired by LSD.[8] For his part, Lennon attributed the colourful prose not to the drug, but to the writings of Lewis Carroll.