Of the original phenomena, light is the most enthralling.

Those who fall in love with practice without science are like a sailor who enters a ship without a helm or a compass, and who never can be certain whither he is going.

Black is like a broken vessel, which is deprived of the capacity to contain anything.

Those who are in love with practice without knowledge are like the sailor who gets into a ship without rudder or compass and who never can be certain whether he is going. Practice must always be founded on sound theory, and to this Perspective is the guide and the gateway; and without this nothing can be done well in the matter of drawing.

...The world wouldn't be the world, without trouble.

Music cannot be called otherwise than the sister of painting, for she is dependent upon hearing, a sense second to sight, and her harmony is composed of the union of its proportional parts sounded simultaneously, rising and falling in one or more harmonic rhythms.

Abbreviators do harm to knowledge and to love.