The book's title, in the original German and in translation, uses a phrase that was well known at the time in many European cultures and had specific meaning. One of its earliest literary uses is in Rabelais's Gargantua and Pantagruel ("gai sçavoir"). It was derived from a Provençal expression (gai saber) for the technical skill required for poetry-writing. The expression proved durable and was used as late as 19th century American English by Ralph Waldo Emerson and E. S. Dallas. It was also used in deliberately inverted form, by Thomas Carlyle in "the dismal science", to criticize the emerging discipline of economics by comparison with poetry. The book's title was first translated into English as The Joyful Wisdom, but The Gay Science has become the common translation since Walter Kaufmann's version in the 1960s. Kaufmann cites The Shorter Oxford English Dictionary (1955) that lists "The gay science (Provençal gai saber): the art of poetry." The book is usually placed within Nietzsche's middle period, during which his work extolled the merits of science, skepticism, and intellectual discipline as routes to mental freedom. The affirmation of the Provençal tradition (invoked through the book's title) is also one of a joyful "yea-saying" to life.