"From a distance, Henri Matisse and Pablo Picasso spent a lifetime in as peers and rivals whose work was inextricably intertwined with one another.[i] "At certain key moments," says art historian Yve-Alain Bois, "both felt they were in a kind of boxing ring -- or that they were players/partners in a sort of game. And the stake of that game was, for both of them, the very practice of painting." Picasso's 1929 "Large Nude in Red Armchair," for example, was a clear parody of Mattisse's 1926 "Odalisque with a Tambourine." His "Acrobat" and "The Dance of Youth" also both clearly reference Matisse's "The Dance." From the other end, Matisse's confidence was powerfully shaken by Picasso's early cubism; he later created his "Reclining Nude in the Studio" as an homage to Picasso's nudes from that same era.[ii] "It's spectacular," says Bois, "the way each tries to introduce, in his own language, some trope of the other -- and to do something with it. It's like: 'You do this, I do that; you do this, I do that.'"