From Giovanni Gentile to Karl Marx, from Wesendonck to Francesco de Sanctis: some of the main authors of the nineteenth and twentieth centuries re-read and reinterpreted by Carlo Sini. Life, the knowledge of life and, between life and knowledge, everyday conversation. The continuous flow of language that makes us both contemporaneous and ancient, children of our time and heirs of traditions and past ages that coexist simultaneously in us and through us. In this world of restless industrial revolution, the discourses of knowledge, thought and art unfold and their subtle, invisible common trait is unveiled.