Jean-Luc Nancy (/nɑːnˈsiː/ nahn-SEE; French: [ʒɑ̃lyk nɑ̃si]; 26 July 1940 – 23 August 2021) was a French philosopher. Nancy's first book, published in 1973, was Le titre de la lettre (The Title of the Letter, 1992), a reading of the work of French psychoanalyst Jacques Lacan, written in collaboration with Philippe Lacoue-Labarthe. Nancy is the author of works on many thinkers, including La remarque spéculative in 1973 (The Speculative Remark, 2001) on Georg Wilhelm Friedrich Hegel, Le Discours de la syncope (1976) and L'Impératif catégorique (1983) on Immanuel Kant, Ego sum (1979) on René Descartes, and Le Partage des voix (1982) on Martin Heidegger.