and three are covers. Two of the covers were originally slated for an abandoned sequel to Bowie's 1973 covers album Pin Ups: Young's "I've Been Waiting for You", taken from his 1969 eponymous debut album, and "I Took a Trip on a Gemini Spaceship" by Norman Odam, or the Legendary Stardust Cowboy, from whom Bowie lifted part of his Ziggy Stardust moniker in 1972. The final cover is "Cactus" by the Pixies, taken from their debut album Surfer Rosa (1988). In his book Strange Fascination, David Buckley discusses the album's musically diversity, from the "edgy rock" of Scary Monsters ("Cactus"), techno ("I Took a Trip on a Gemini Spaceship"), American punk ("I've Been Waiting For You"), drum and bass ballad ("I Would Be Your Slave"), riff rock ("Afraid"), quasi-reggae ("5.15 The Angels Have Gone") and 1971-era pop ("Everyone Says 'Hi). Other reviewers have classified Heathen as art rock and art pop. Compared to previous albums, the songs feature ties between the melodies, harmonies and arrangements, predominantly on "Sunday", "Slip Away" and "Afraid". Bowie said he wanted to capture the mood of Bob Dylan's Time Out of Mind (1997), and based "Sunday", "Heathen (The Rays)", "I Would Be Your Slave" and "5.15 The Angels Have Gone" off of Richard Strauss's Four Last Songs. Thematically, Heathen continues the spirituality of Outside (1995), Earthling (1997) and Hours (1999). Depicting a godless world, the record also presents Bowie's reflections on ageing. He told Interview that once you reach a certain age, you realise "you're not growing anymore", "your body's strength is diminishing" and once aware, "you've got to let it go". Comparing Heathen and Hours, author Dave Thompson says that both share similar moods, reflections and "deep, personal beauty". However, compared to the melancholic nostalgia that pervaded Hours, biographer Nicholas Pegg says that Heathen focuses on feelings of existential dread, particularly on "Sunday", "Afraid" and "Heathen (The Rays)". Pegg also analyses the feeling of anxiety, stating that unlike Diamond Dogs and Station to Station (1976), throughout Heathen the anxiety is of "a happy, fulfilled mind struggling to come to terms with imitations of mortality." Bowie elaborated in Interview: "It's a head-spinning dichotomy of the lust for life against the finality of everything." He also defined the album's protagonist as a lost 21st-century man. Connections with 9/11 Due to its subject matter, recording location and timing of its release, commentators at the time suggested that