I roamed the countryside searching for answers to things I did not understand. Why shells existed on the tops of mountains. How the various circles of water form around the spot which has been struck by a stone, and why a bird sustains itself in the air.

The painter will produce pictures of little merit if he takes the works of others as his standard: but if he will apply himself to learn from the objects of nature he will produce good results. This we see was the case with the painters who came after the time of the Romans, for they continually imitated each other, and from age to age their art steadily declined.

The painter strives and competes with nature.

Of the original phenomena, light is the most enthralling.

Although human ingenuity may devise various inventions which, by the help of various instruments, answer to one and the same purpose, yet will it never discover any inventions more beautiful, more simple or more practical than those of nature, because in her inventions there is nothing lacking and nothing superfluous; and she makes use of no counterpoise when she constructs the limbs of animals in such a way as to correspond to the motion of their bodies, but she puts into them the soul of the body.

Nature appears to have been the cruel stepmother rather than the mother of many animals.