Gargoyles were the complement to saints; Leonardo's caricatures were complementary to his untiring search for ideal beauty. And gargoyles were the expression of all the passions, the animal forces, the Caliban gruntings and groanings which are left in human nature when the divine has been poured away. Leonardo was less concerned than his Gothic predecessors with the ethereal parts of our nature, and so his caricatures, in their expression of passionate energy, merge imperceptibly into the heroic.

Sweeping, confident articles on the future seem to me, intellectually, the most disreputable of all forms of public utterance.

We are part of a great whole. All living things are our brothers and sisters.

Evidently one cannot look for long at the Last Supper without ceasing to study it as a composition, and beginning to speak of it as a drama. It is the most literary of all great pictures, one of the few of which the effect may largely be conveyed - can even be enhanced - by description.

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.

You have no idea what portrait painters suffer from the vanity of their sitters.

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.