Only an inventor knows how to borrow, and every man is or should be an inventor.

Discovery consists of seeing what everybody has seen and thinking what nobody else has thought.

Simplicity is the ultimate sophistication.

Doubt is the father of invention.

I believe in human dignity as the source of national purpose, human liberty as the source of national action, the human heart as the source of national compassion, and in the human mind as the source of our invention and our ideas.

Where a new invention promises to be useful, it ought to be tried.

I do not think there is any thrill that can go through the human heart like that felt by the inventor as he sees some creation of the brain unfolding to success... Such emotions make a man forget food, sleep, friends, love, everything.

The march of invention has clothed mankind with powers of which a century ago the boldest imagination could not have dreamt

If you build a better mousetrap, you will catch better mice.

A tool is but the extension of a man's hand, and a machine is but a complex tool. And he that invents a machine augments the power of a man and the well-being of mankind.

- Henry Ward Beecher, in Proverbs from Plymouth Pulpit-Business

Before then any man might instantly use what another had invented; so that the inventor had no special advantage from his own invention. The patent system changed this; secured to the inventor, for a limited time, the exclusive use of his invention; and thereby added the fuel of interest to the fire of genius, in the discovery and production of new and useful things.

- Abraham Lincoln, in his Second Lecture on Discoveries and Inventions, February 11, 1859