The Ethics of Ambiguity (French: Pour une morale de l'ambiguïté) is Simone de Beauvoir's second major non-fiction work. It was prompted by a lecture she gave in 1945, where she claimed that it was impossible to base an ethical system on her partner Jean-Paul Sartre's major philosophical work Being and Nothingness (French: L'Être et le néant).[citation needed] The following year, over a six-month period, she took on the challenge, publishing the resulting text first as installments in Les Temps modernes and then, in November 1947, as a book.