No nude, however abstract, should fail to arouse in the spectator some vestige of erotic feeling, even if it be only the faintest shadow - and if it does not do so it is bad art and false morals.

The difference between what we see and a sheet of white paper with a few thin lines on it is very great. Yet this abstraction is one which we seem to have adopted almost instinctively at an early stage in our development, not only in Neolithic graffiti but in early Egyptian drawings. And in spite of its abstract character, the outline is responsive to the least tremor of sensibility.

Great works of art can be produced in barbarous societies - in fact the very narrowness of primitive society gives their ornamental art a peculiar concentration and vitality. At some time in the ninth century one could have looked down the Seine and seen the prow of a Viking ship coming up the river. Looked at today in the British Museum, it is a powerful work of art; but to the mother of a family trying to settle down in her little hut, it would have seemed less agreeable - as menacing to her civilisation as the periscope of a nuclear submarine.

The history of art cannot be properly understood without some reference to the history of science. In both we are studying the symbols by which man affirms his mental scheme, and these symbols, be they pictorial or mathematical, a fable or formula, will reflect the same changes.

The eye instinctively looks for analogies and amplifies them, so that a face imagined in the pattern of a wallpaper may become more vivid than a photograph.

A visual experience is vitalizing. Whereas to write great poetry, to draw continuously on one's inner life, is not merely exhausting, it is to keep alight a consuming fire.

A racist system inevitably destroys and damages human beings; it brutalizes and dehumanizes them, blacks and whites alike.