"When I put a green, it it not grass. When I put a blue, it is not the sky."

"I interpret nature and submit it to the spirit of the picture."

Henri Matisse

It was the uprush of violence as much as the earthy physicality of the finished work that shocked people. Matisse said he himself took fright, like the Douanier Rousseau, who sometimes had to open a window to let out the elemental force of his own painting. In Dance and Music, Matisse attempted simultaneously to release and contain that force. "At the precise moment when raging bands were milling about in front of his huge canvases, tearing him to pieces and cursing him," wrote Sembat, "he confessed coolly to us: 'What I want is an art of balance, of purity, an art that won't disturb or trouble people. I want anyone tired, worn down, driven to the limits of endurance, to find calm and repose in my painting'."

Hilary Spurling, from Matisse the Master, vol 2, which won the Whitbread Prize last night.