Guillaume Apollinaire was as firm as Whistler on the principle that literature and painting must be kept separate. Each has its own means of expression, and its aim can only be understood within the logic of that means. As he wrote in 1907, in an essay in praise of Matisse:

Il n’y a pas de rapport de la peinture à la littérature, et je me suis efforcé de n’établir à cet égard aucune confusion. C’est que chez Matisse l’expression plastique est un but, de même que chez le poète l’expression lyrique. (100)1

Painting has no connection with literature, and I have done my best not to give rise to any confusion on this subject. For in Matisse’s work, plastic expression is a goal, in the same way as lyric expression in a poet’s work.