Someone Else's Song by Wilco delves into the theme of feeling like an outsider or an imitator in one's own life. The song reflects on the notion of self-doubt and the struggle to carve out a unique identity when everything feels borrowed from others. Key themes include introspection, identity crisis, and the pressure to be original in a world where everything seems derivative. Poignant moments include lines that reveal the singer's vulnerability and the sense of melancholy that comes with recognizing one's own limitations and the search for authenticity.