Down through the ages, it was a generally accepted fact that art had a purpose. In fact, one might go so far to say the view was that it had to have a purpose. There was a broad range of acceptable "purposes" available to the working artist but nonetheless, the art he or she created had to have a reason to exist. An artist's work may educate or enlighten. It might amuse or entertain, it might provoke outrage or invoke great religious fervour. Whatever the case, it had to do something. Art was to be used. In fact, as the only means of visually representing an idea or event, for many centuries it was simply too important to be taken lightly or toyed with, even by the artists themselves. No one told them this. It was just understood. In fact, most probably very few artist of antiquity never even considered the self-indulgent possibility in their work.
For Edouard Manet the act of painting and the painting itself were sufficient reason for it to exist. It's uncertain where the phrase "Art for art's sake" originated, the rebel painters of the late 1800's were only to glad to adopt it as their own, if they did not in fact invent it. Manet's scandalous 1863 painting Le dejeuner sur l'herbe (Luncheon on the Grass) may well be the first such work of art to embrace "art for art's sake". The work refuses categorisation. It is not a simple genre scene involving a picnic on the grass as the name seems to imply. Neither is it a replay of classical themes despite the poses of the figures, which Manet borrowed from classical etchings.
Manet appears to have been conscious of just how radical the painting was. It provoked dismay and controversy even at the Salon de Refuse` where it was first exhibited. Manet was convinced the importance of the painting lay not in its subject matter but in the painting itself. The work is an amalgamation, pulled together from various sources, including photographs. The nude woman's face is photographically realistic unlike the rest of her nude body - which seems flat and perhaps rather alien. The figure in the background seems too large and almost a painted backdrop. In a very real sense, Manet was a bridge between the "useful" art of the past and the, "modern" art we know today wherein the artist rules!