Science and Reason

The painter who draws by practice and judgment of the eye without the use of reason is like the mirror which reproduces within itself all the objects which are set opposite to it without knowledge of the same.

Things that are separate shall be united and acquire such virtue that they will restore to man his lost memory.

I have discovered that a screw-shaped device such as this, if it is well made from starched linen, will rise in the air if turned quickly.

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.

I am not to blame for putting forward, in the course of my work on science, any general rule derived from a previous conclusion.

There is no result in nature without a cause; understand the cause and you will have no need of the experiment.

I abhor the supreme folly of those who blame the disciples of nature in defiance of those masters who were themselves her pupils.

The instant the atmosphere is illuminated it will be filled with an infinite number of images which are produced by the various bodies and colors assembled in it. And the eye is the target, a lodestone, of these images.

Experience never misleads; what you are misled by is only your judgment, and this misleads you by anticipating results from experience of a kind that is not produced by your experiments.

Experience, the interpreter between creative nature and the human race, teaches the action of nature among mortals: how under the constraint of necessity she cannot act otherwise than as reason, who steers her helm, teaches her to act.

The eye transmits its own image through the air to all the objects which face it, and also receives them on its own surface, whence the “sensus communis

Oh! Speculators on things, boast not of knowing the things that nature ordinarily brings about; but rejoice if you know the end of those things which you yourself device.

Necessity is a guardian in Nature.

One day the world will look upon research upon animals as it now looks upon research on human beings.

It is the infinite alone that cannot be attained, for if it could it would become finite.

Perspective is a most subtle discovery in mathematical studies, for by means of lines it causes to appear distant that which is near, and large that which is small.

He who in reasoning cites authority is making use of his memory rather than of his intellect.

The light and heat of the universe comes from the sun, and its cold and darkness from the withdrawal of the sun.

Experience never errs; it is only your judgments that err by promising themselves effects such as are not caused by your experiments.

Those who condemn the supreme certainty of mathematics feed on confusion, and can never silence the contradictions of the sophistical sciences which lead to eternal quackery.

Many will think they may reasonably blame me by alleging that my proofs are opposed to the authority of certain men held in the highest reverence by their inexperienced judgments; not considering that my works are the issue of pure and simple experience.

Why are the bones of great fishes, and oysters and corals and various other shells and sea-snails, found on the high tops of mountains that border the sea, in the same way in which they are found in the depths of the sea?

The organ of perception acts more readily than judgment.

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