Dave Grohl stated Cobain believed "Music comes first, lyrics come second". Cobain focused, foremost, on the melodies of his songs.Cobain complained when fans and rock journalists attempted to decipher his singing and extract meaning from his lyrics, writing "Why in the hell do journalists insist on coming up with a second-rate Freudian evaluation of my lyrics, when 90 percent of the time they've transcribed them incorrectly?" While Cobain would insist of the subjectivity and unimportance of his lyrics, he was known to labour and procrastinate in writing them, often changing the content and order of lyrics during performances.Cobain would describe his lyrics himself as "a big pile of contradictions. They're split down the middle between very sincere opinions that I have and sarcastic opinions and feelings that I have and sarcastic and hopeful, humorous rebuttals toward cliché bohemian ideals that have been exhausted for years."
Cobain originally wanted Nevermind to be divided into two sides. A "Boy"-side, for the songs written about the experiences of his early life and childhood, and a "Girl"-side, for the songs written about his dysfunctional relationship with Tobi Vail Charles R. Cross would write "In the four months following their break-up, Kurt would write a half dozen of his most memorable songs, all of them about Tobi Vail". Though "Lithium" had been written before Cobain knew Vail, the lyrics of the song were changed to reference her.Cobain would say in an interview with Musician that "some of my very personal experiences, like breaking up with girlfriends and having bad relationships, feeling that death void that the person in the song is feeling. Very lonely, sick."While Cobain would regard In Utero "for the most part very impersonal" on the album he dealt with the childhood divorce of his parents, his newfound fame and the public image and perception of himself and Courtney Love on "Serve the Servants", with his enamoured relationship with Love conveyed through lyrical themes of pregnancy and the female anatomy on "Heart-Shaped Box". Cobain wrote "Rape Me" not only as an objective discussion of rape, but a metaphorical protest against his treatment by the media. He wrote about drug addiction and abortion on "Pennyroyal Tea", as well as women's rights and the life of Frances Farmer on "Frances Farmer Will Have Her Revenge on Seattle".
Cobain was affected enough to write the song "Polly" from Nevermind, after reading a newspaper story of an incident in 1987, where a young girl was kidnapped after attending a punk rock show, then raped and tortured with a blowtorch. She managed to escape after gaining the trust of her captor through flirting with him.After seeing Nirvana perform, Bob Dylan would cite "Polly" as the best of Nirvana's songs, and was quoted as saying about Cobain, "the kid has heart". Patrick Süskind, whose novel Perfume: The Story of a Murderer inspired Cobain to write the song "Scentless Apprentice" from In Utero. A historical horror novel about a perfumer's apprentice born with no body odor of his own but with a highly developed sense of smell, and who attempts to create the "ultimate perfume" by killing virgin women and taking their scent.
Cobain immersed himself in artistic projects throughout his life, as much so as he did in songwriting. The sentiments of his art work followed the same subjects of his lyrics, often expressed through a dark and macabre sense of humour. Noted was his fascination with physiology, his own rare medical conditions, and the human anatomy. Often unable to afford artistic resources, Cobain would improvise with materials, painting on board games and album sleeves, and painting with an array of substances, including his own bodily fluids. The artwork seen in his Journals would later draw acclaim as being of a high artistic standard. Many of Cobain's paintings, collages, and sculptures would appear in the artwork of Nirvana's albums. His artistic concepts would feature notably in Nirvana's music videos; the production and direction of which were acrimonious due to the artistic perfectionism of his visions.
Cobain would contribute backing guitar for a spoken word recording of beat poet William S. Burroughs' entitled "the "Priest" they called him". Cobain regarded Burroughs as a hero. During Nirvana's European tour Cobain kept a copy of Burroughs' Naked Lunch, purchased in a London bookstall. Ana Finel-Honigman, in her introduction to an interview with the artist Stella Vine on the Saatchi Gallery website, described Vine's art as bitterly honest in the same way Cobain's songs were; "acid outrage over adult lies and injustice", Holden Caulfield's observations about "a world filled with phonies", and Sylvia Plath's poetry an "over-heated anger and bitterness at the world's betrayals".