Genius is not inspired. Inspiration is perspiration.

Unfortunately, there seems to be far more opportunity out there than ability.... We should remember that good fortune often happens when opportunity meets with preparation.

X-rays ... I am afraid of them. I stopped experimenting with them two years ago, when I came near to losing my eyesight and Dally, my assistant practically lost the use of both of his arms.

It is apparent to me that the possibilities of the aeroplane, which two or three years ago were thought to hold the solution to the [flying machine] problem, have been exhausted, and that we must turn elsewhere.

There is no limit to which a man will not go to avoid thinking.

The doctor of the future will give no medicine, but will involve the patient in the proper use of food, fresh air and exercise

It is astonishing what an effort it seems to be for many people to put their brains definitely and systematically to work.