Déraille literally means "goes off the rails" (like a train) or "derails". It's an evocative verb that suggests losing control or going crazy.
In the song, Claudio Capéo uses it to question his own sanity and perspective, singing, "C'est peut être moi qui déraille" (Maybe it's me who's going off the rails). This word perfectly captures the feeling of doubt and rebellion against societal norms, making it both interesting and memorable.
Ever feel like you're the only one who sees how weird the world is? That's the whole mood of this song. Claudio Capéo starts by wondering, "Je sais pas vous / C'est peut être moi qui suis fou" (I don't know about you / Maybe I'm the crazy one). He feels like an outsider, a sensitive dreamer who just can't accept that society is run by "dix abrutis en costard" (ten idiots in suits). It's a powerful song about refusing to be a passive observer in your own life.
Instead of just complaining, he decides to take control. He declares, "voilà mes lois je me les suis fixées" (so here are my laws, I've set them for myself) and insists on living by his own truth and reality. The chorus is just him repeating "Laissez-moi" (Leave me alone), a simple but strong demand for the freedom to be himself. He's tired of false hopes and people trying to dim his light, deciding instead, "j'avance vers ce que j'ai choisi" (I'm moving towards what I've chosen).