Each side of the album is a continuous piece of music. The five tracks on each side reflect various stages of human life, beginning and ending with a heartbeat, exploring the nature of the human experience, and (according to Waters) "empathy". "Speak to Me" and "Breathe" together stress the mundane and futile elements of life that accompany the ever-present threat of madness, and the importance of living one's own life "Don't be afraid to care". By shifting the scene to an airport, the synthesiser-driven instrumental "On the Run" evokes the stress and anxiety of modern travel, in particular Wright's fear of flying. "Time" examines the manner in which its passage can control one's life and offers a stark warning to those who remain focused on mundane aspects; it is followed by a retreat into solitude and withdrawal in "Breathe (Reprise)". The first side of the album ends with Wright and vocalist Clare Torry's soulful metaphor for death, "The Great Gig in the Sky".