In 1907, Apollinaire introduced Picasso to Georges Braque, another young painter deeply interested in Cézanne. Braque and Picasso worked together closely; Braque later said they were "roped together like mountaineers" as they explored a new approach to organizing pictorial space. While "Les Demoiselles" cleared the ground, Cubism was a joint construction, to the extent that sometimes Picasso and Braque could not tell their work apart. Afterwards, describing Braque's role in Cubism's later evolution, Picasso called him "just a wife," simultaneously dismissing both his colleague and women. But Braque's integral role in Cubism's initial invention cannot be disputed.
During the summer of 1908 Braque went to L'Estaque, in southern France, where his idol Cézanne had painted before him. The way in which Cubism sliced and diced pictorial space, attempting to see all angles at once, to paint an analysis of a form instead of its appearance, is illustrated by the comparison of Braque's painting "Houses at L'Estaque" with a photograph of the view that Braque was painting. (The photograph was taken by Picasso's dealer, Daniel- Henry Kahnweiler.) Scale and perspective are gone; forms are simplified into blocks. There is no distinction between foreground and background; the shapes of the painting seem to be stacked on top of each other.
The influence of Braque and Cézanne is clear in Picasso's paintings from the summer of 1909, which he spent with Fernande in Horta de Ebro. Braque and Picasso had extended Cézanne's method landscape painting to the point where a view became an almost monochromatic field of faceted forms.
This method, extended and developed, led to paintings that were almost indecipherable combinations of fragmented facets in grays and browns. Kahnweiler was later to name this stage of Picasso and Braque's work Analytical Cubism, because it was based on an analytical description of objects. Picasso's portrait of Kahnweiler, in which he splits up his sitter into a multiplicity of discontinuous surfaces, exemplifies his work during this period, showing how far he took the results of his summer in Horta. Describing this period, Kahnweiler wrote, "The great step has been made. Picasso has exploded homogenous form." Indeed, Cubism was an explosion; not only did Cubist paintings resemble the shrapnel of their ostensible subjects, but the intent was a kind of joyous destruction of the tradition of Western painting and the result was a revolution in art history.
Meanwhile, Picasso had grown tired of his struggling-artist existence at the Bateau-Lavoir; in the fall of 1909, he and Fernande moved to an new apartment, with a maid, near the Place Pigalle in Paris. He exhibited internationally, from Moscow to New York. His collaboration with Braque continued, and the two spent the August of 1911 together painting in Céret. There he began working with more easily legible imagery than that used in the nearly abstract work of the year before. Braque began stenciling letters and words on his paintings, and Picasso followed suit; his word-filled paintings became riddles, puns and love-tokens. Picasso began a new affair in the fall of 1911, with Eva Gouel; instead of painting portraits of her, he marked the presence of this new muse by incorporating the words "ma jolie," meaning "my pretty," into his paintings.