I have heard articulate speech produced by sunlight I have heard a ray of the sun laugh and cough and sing! … I have been able to hear a shadow, and I have even perceived by ear the passage of a cloud across the sun's disk.

The most successful men in the end are those whose success is the result of steady accretion. It is the man who carefully advances step by step, with his mind becoming wider and wider - and progressively better able to grasp any theme or situation - persevering in what he knows to be practical, and concentrating his thought upon it, who is bound to succeed in the greatest degree.

Don't keep forever on the public road, going only where others have gone and following one after the other like a flock of sheep. Leave the beaten track occasionally and dive into the woods.

I have had the feeling that a properly constructed flying-machine should be capable of being flown as a kite; and conversely, that a properly constructed kite should be capable of use as a flying-machine when driven by its own propellers.

The achievement of one goal should be the starting point of another.

Man is an animal which, alone among the animals, refuses to be satisfied by the fulfillment of animal desires.

Leave the beaten track behind occasionally and dive into the woods. Every time you do you will be certain to find something you have never seen before.