On Se Sait Par Cœur paints the picture of a couple stuck in a love-hate stalemate. Calogero compares their bedroom to the Berlin Wall, their seasons turned upside-down, and the floor disappearing beneath their feet. These vivid images show how unnatural and fragile their relationship has become, yet both partners know each other par cœur—“by heart”—so letting go feels as frightening as an earthquake.
Throughout the song the singer asks the same haunting question: Who will make the final move? Every chorus circles back to the fear of separation, the idea that if one leaves, the other might “die” inside. The lovers wonder if they are still together out of affection or simple panic, and whether surrendering to the current might finally carry them to a calmer ocean. It is a powerful study of attachment, pride, and the moment just before goodbye.