My father was the most rational and the most dispassionate of men.

Ten decimal places of π are sufficient to give the circumference of the earth to a fraction of an inch, and thirty decimal places would give the circumference of the visible universe to a quantity imperceptible to the most powerful microscope.

James Edward Oliver might have been one of the great mathematicians of his time had he not been absolutely wanting in the power of continuous work.

Aerial flight is one of that class of problems with which man will never be able to cope. . . . The example of the bird does not prove that man can fly. Imagine the proud possessor of the aeroplane darting through the air at a speed of several hundred feet per second. It is the speed alone that sustains him. How is he ever going to stop?

Construction of an aerial vehicle which can carry even a single man . . . requires the discovery of some new metal or force. Even with such a discovery, we could not expect one to do more than carry its owner.

Flight by machines heavier than air is unpractical and insignificant, if not utterly impossible.

My first undertaking in the way of scientific experiment was in the field of economics and psychology.