The first manifestations of Cubism took people by surprise because their minds, ill-adapted as they are to the idea of movement, are never able, on t… - Albert Gleizes

If we wished to relate the space of the [Cubist] painters to geometry, we should have to refer it to the non-Euclidean mathematicians; we should have to study, at some length, certain of Riemann's theorems.

Never had the critics been so violent as they were at that time. From which it became clear that these paintings - and I specify the names of the painters who were, alone, the reluctant causes of all this frenzy: Jean Metzinger, Le Fauconnier, Fernand Léger, Robert Delaunay and myself - appeared as a threat to an order that everyone thought had been established forever.

There is not a canvas of that time that does not foreshadow the overthrow of the foundations on which the human race thought itself firmly established, where it felt itself secure. At the moment when the Ballets Russes were at their height, when the Neo-Impressionists and Fauves had dispensed with the drawing style of the Renaissance because it could not contain the purity of the colour - these humbly painted, angular, grey, ascetic pictures were, really, an unwelcome sight. It was not any upheaval of a geological nature that they prefigured, but a cataclysm in the human order. No tremor of the earth was registered, but a tremor of the spirit that disturbed the intellect of civilised man, too long the slave of his immobilised senses. At last he was beginning to suspect that something dangerous was approaching.