Jean-François Lyotard (Vincennes, August 10, 1924 – Paris, April 21, 1998) was a French philosopher whose work is placed within poststructuralist and postmodern philosophy. He was primarily concerned with issues in aesthetics, ethics, and political philosophy. The central focus of his work was how one can justly bear witness to the unrepresentable and the disputes between various forms of speech. He himself rejected every attempt to develop a universal and overarching framework for this. Lyotard gained international fame with his book La condition postmoderne (1979), which popularized the term postmodernism. He considered Le différend (1983) to be his most important work.