Why does the eye see a thing more clearly in dreams than with the imagination being awake? - Leonardo da Vinci

There is no certainty in sciences where one of the mathematical sciences cannot be applied, or which are not in relation with these mathematics.

Fire is to represent truth because it destroys all sophistry and lies; and the mask is for lying and falsehood which conceal truth.

Raphael, on the other hand, found only beautiful sweetness everywhere. The tragedies of life failed to touch the young painter, who blotted from view all struggle and sorrow, and, in spite of the misery which had befallen his nation, could still rejoice in the sensuous beauty of the world. There was another side to the Renaissance, dependent neither on beauty nor heroic grandeur, yet sharing in both through qualities of its own.