Each man is always in the middle of the surface of the earth and under the zenith of his own hemisphere, and over the centre of the earth.

The length of a man's outspread arms is equal to his height.

Knowledge of the past and of the places of the earth is the ornament and food of the mind of man.

I have always felt it is my destiny to build a machine that would allow man to fly.

When once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been, and there you will always long to return.

The senses are of the earth, the reason stands apart from them in contemplation.