The memory of benefits is a frail defence against ingratitude.

The eye transmits its own image through the air to all the objects which face it, and also receives them on its own surface, whence the "sensus communis" takes them and considers them.

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

Where the spirit does not work with the hand, there is no art.

Nothing is so much to be feared as Evil Report.

... we might say that the earth has a spirit of growth; that its flesh is the soil, its bones the arrangement and connection of the rocks of which the mountains are composed, its cartilage the tufa, and its blood the springs of water.

I say that the power of vision extends through the visual rays to the surface of non-transparent bodies, while the power possessed by these bodies extends to the power of vision.