Phil Lynott's defiant spirit colours many of Thin Lizzy's tunes, but the rocker also possessed a weary sadness. He describes a planet overrun with pollution on the bluesy environmental anthem “Mama Nature Said” and ruminates on lost youth in the soulful ballad “Shades of a Blue Orphanage”. A lot of Lynott's melancholy came from a lifelong sense of rootlessness, something he explored on the drifter's lament “Southbound”.