Margaret Walch, "The Colors of Matisse". In: Color Source Book, Charles Scribner's Sons, New York 1979
"I finally came to consider colors as forces, to be assembled as inspiration dictates. Colors can be transformed by relation; a black becomes red-black when you put it next to a rather cold color like Prussian blue, blue-black if you put it alongside a color that has an extremely hot basis: orange, for example. From that point on, I began working with a palette especially composed for each painting while I was working on it, which meant I could eliminate one of the primordial colors, like a red or a yellow or a blue, from my painting. And it goes right against neoimpressionist theory, which is based on optical mixing and color constraints, each color having its reaction. For example: if there is red, there has to be a green…. In a picture, neoimpressionist color reactions involved dominants. These dominants create reactions, but they have to remain dominants…. In terms of intensity, my reactions aren’t subordinate to the dominants, they’re on the same level… All the colors sing together; their strength is determined by the needs of the chorus. It’s like a musical chord."
Chatting with Henri Matisse – The Lost 1941 Interview, editor Serge Guilbaut, Getty Research Institute, Los Angeles 2013