Necessity is the mistress and guide of nature.

The noblest pleasure is the joy of understanding.

Obstacles cannot crush me. Every obstacle yields to stern resolve. He who is fixed to a star does not change his mind.

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.

Nature is so delightful and abundant in its variations that among trees of the same kind there would not be found one which nearly resembles another, and not only the plants as a whole, but among their branches, leaves, and fruit, will not be found one which is precisely like another.

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

When the thing taken into union is perfectly adapted to that which receives it, the result is delight and pleasure and satisfaction.