... 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.

Common Sense is that which judges the things given to it by other senses.

O Time with your teethy years! You swallow up all things little by little in a slow-motion, wrinkling process of dying.

The motive power is the cause of all life.

Sculptured figures which appear in motion, will, in their standing position, actually look as if they were falling forward.

He who does not understand the supreme certainty of mathematics is wallowing in confusion.

Experience is a truer guide than the words of others.