Gilles Deleuze (1925-1995) was professor of philosophy at the university of Paris viii. He is a key figure in poststructuralism, and one of the most influential philosophers of the twentieth century. Felix guattari (1930...Gilles Deleuze (1925-1995) was professor of philosophy at the university of Paris viii. He is a key figure in poststructuralism, and one of the most influential philosophers of the twentieth century. Felix guattari (1930-1992) was a psychoanalyst at the la borde clinic, as well as being a major social theorist and radical activist.