Proto-Cubism that Metzinger was the first to recognize explicitly and implicitly the significance of the use of "a free, mobile perspective", and the "mixing... of the successive and the simultaneous". He was the first to write of the fact that artists had abandoned traditional perspective and were now free to move around their subjects to paint them from various points in space, and at various moments in time. Metzinger's role at center of Cubism both as a painter and theorist prompted Guillaume Apollinaire to write of Picasso, Braque and Metzinger as the first three Cubist painters. Now well beyond the teachings
Crystal Cubism towards the end of 1916, with an art world still under the pressures of war, to show the parallels between the poetic theories of Guillaume Apollinaire of Max Jacob and himself in marking the burgeoning of a new era for poetry and artistic reflection. In "Nord-Sud" Reverdy, with the help of Dermée and Georges Braque, exposed his literary theories, and outlined a coherent theoretical stance on the latest developments in Cubism. His treatise "On Cubism", published in the first issue of "Nord-Sud", did so perhaps most influentially. With his characteristic preference for offense rather than defense, Reverdy launched an attack