Mirrors by Niall Horan delves into the theme of self-realization and the struggle of seeing oneself clearly in the reflection of another's eyes. The song captures the emotional journey of understanding how one's actions and thoughts are perceived by others. As Horan reflects on his own identity, he explores the challenges of self-awareness and the pursuit of authenticity. Key themes include introspection, personal growth, and the quest for genuine connections. Particularly poignant moments in the song occur when Horan grapples with the dissonance between how he sees himself and how he is seen by others, urging listeners to embrace their true selves amid societal pressures.