“[Matisse] valued, and was determined to maintain, the traditional, physical substantiality of figural representation. But eventually, the very luminous substance of painting itself came to fulfill the functions that form and structure had fulfilled earlier.
Matisse said that the peak of his aspirations was the art of Giotto. Looking for a comparison for the revolution that Matisse effected, what Giotto did is precisely what comes to mind. There, too, we see pictorial art in an essential transition, wherein the substantiality of form and of luminous color momentarily combine. Matisse’s revolution, of course, turned art in the direction opposite to Giotto’s. Matisse was alone when he began to discover that the very colored stuff of which paintings are made can have an independent reality no less bodied and emotionally charged than the forms paintings depict. Others came to join him, and it might be expected that the magnitude of Matisse’s discovery was such that it would have been emulated. What happened, instead, was that his original imperative — somehow to maintain for painting a power equivalent to that of traditional figural art — was often forgotten. And without that, there could be only painting whose color was merely a decoration. The imperative was inseparable from the conventions of representation. A picture did not need to be representational in the old, depictive sense, as Matisse’s last cutouts demonstrate. But it did have to be, in the very broadest sense, a representation. Otherwise, it would have nothing to show.”
John Elderfield, Henri Matisse: A Retrospective, p.13-14