Backwards Traveller by Paul McCartney speaks to the theme of time and exploration of one's past. The song portrays a nostalgic journey where the protagonist feels like a traveler moving backward through time. Key themes include reflection, introspection, and the passage of time. Poignant moments in the song include the lines where the lyrics express a longing to revisit and understand moments in the past, illustrating the human desire to reconcile with past experiences.