A universe without law would be a universe without order, without the possibility of science, and the manifestations of an intelligent governor and creator.

All knowledge is profitable; profitable in its ennobling effect on the character, in the pleasure it imparts in its acquisition, as well as in the power it gives over the operations of mind and of matter. All knowledge is useful; every part of this complex system of nature is connected with every other. Nothing is isolated. The discovery of to-day, which appears unconnected with any useful process, may, in the course of a few years, become the fruitful source of a thousand inventions.

All parts of the material universe are in constant motion and though some of the changes may appear to be cyclical, nothing ever exactly returns, so far as human experience extends, to precisely the same condition.

Astronomy was not studied by Kepler, Galileo, or Newton for the practical applications which might result from it, but to enlarge the bounds of knowledge, to furnish new objects of thought and contemplation in regard to the universe of which we form a part; yet how remarkable the influence which this science, apparently so far removed from the sphere of our material interests, has exerted on the destinies of the world!

If, again with the light of science, we trace forward into the future the condition of our globe, we are compelled to admit that it cannot always remain in its present condition; that in time, the store of potential energy which now exists in the sun and in the bodies of celestial space which may fall into it will be dissipated in radiant heat, and consequently the earth, from being the theatre of life, intelligence, of moral emotions, must become a barren waste.

In this country, science is almost exclusively prosecuted by those engaged in the laborious and exhaustive employment of imparting instruction. Science among us brings comparatively little emolument and is accompanied with but little honor.

It is not surprising that science has made comparatively little advance among us, but that … it should have made so much.

Man does not live by bread alone, there are other wants to be supplied, and even in a practical point of view, a single thought may be fraught with a thousand useful inventions.

Meteorology has ever been an apple of contention, as if the violent commotions of the atmosphere induced a sympathetic effect on the minds of those who have attempted to study them.

Modern civilization depends on science … James Smithson was well aware that knowledge should not be viewed as existing in isolated parts, but as a whole, each portion of which throws light on all the other, and that the tendency of all is to improve the human mind, and give it new sources of power and enjoyment … narrow minds think nothing of importance but their own favorite pursuit, but liberal views exclude no branch of science or literature, for they all contribute to sweeten, to adorn, and to embellish life … science is the pursuit above all which impresses us with the capacity of man for intellectual and moral progress and awakens the human intellect to aspiration for a higher condition of humanity.
[Joseph Henry was the first Secretary of the Smithsonian Institution, named after its benefactor, James Smithson.]

Nearly all the great inventions which distinguish the present century are the results, immediately or remotely, of the application of scientific principles to practical purposes, and in most cases these applications have been suggested by the student of nature, whose primary object was the discovery of abstract truth.

No country in the world is so much indebted for its progress in power and intelligence to science than ours, and yet no country does so little to encourage or advance it.

Nothing can be unworthy of being investigated by man, which was thought worthy of being created by God.

Nothing in the whole system of nature is isolated or unimportant. The fall of a leaf and the motion of a planet are governed by the same laws. … It is in the study of objects considered trivial and unworthy of notice by the casual observer that genius finds the most important and interesting phenomena. It was in the investigation of the varying colors of the soap-bubble that Newton detected the remarkable fact of the fits of easy reflection and easy refraction presented by a ray of light in its passage through space, and upon which he established the fundamental principle of the present generalization of the undulatory theory of light. … The microscopic organization of animals and plants is replete with the highest instruction; and, surely, in the language of one of the fathers of modern physical science, “nothing can be unworthy of being investigated by man which was thought worthy of being created by GOD.”

Placed in a universe of constant change, on an isolated globe surrounded by distant celestial objects on all sides, subjected to influences of various kinds, it is a sublime occupation to measure the earth and weigh the planets, to predict their changes, and even to discover the materials of which they are composed; to investigate the causes of the tempest and volcano; to bring the lightning from the clouds; to submit it to experiment by which it shall reveal its character; and to estimate the size and weight of those invisible atoms which constitute the universe of things.

The general mental qualification necessary for scientific advancement is that which is usually denominated “common sense,” though added to this, imagination, induction, and trained logic, either of common language or of mathematics, are important adjuncts.

The great object of human thought is the discovery of truth or, in other words, to arrive at conceptions and expressions of things which shall agree with the nature of things.

The incessant call in this country for practical results and the confounding of mechanical inventions with scientific discoveries has a very prejudicial influence on science. … A single scientific principle may include a thousand applications and is therefore though if not of immediate use of vastly more importance even in a practical view.

The man imbued with the proper spirit of science does not seek for immediate pecuniary reward from the practical applications of his discoveries, but derives sufficient gratification from his pursuit and the consciousness of enlarging the bounds of human contemplation, and the magnitude of human power, and leaves to others to gather the golden fruit he may strew along his pathway.

The man of true genius never lives before his time, he never undertakes impossibilities, and always embarks on his enterprise at the suitable place and period. Though he may catch a glimpse of the coming light as it gilds the mountain top long before it reaches the eyes of his contemporaries, and he may hazard a prediction as to the future, he acts with the present.

The operations of the universe are unlimited, and in the great book of nature, man has scarcely read more than the title page or the preface.

The person who thinks there can be any real conflict between science and religion must be either very young in science or very ignorant in religion.

The seeds of great discoveries are constantly floating around us, but they only take root in minds well-prepared to receive them.

The study of abstract science … offers unbounded fields of pleasurable, healthful, and ennobling exercise to the restless intellect of man, expanding his powers and enlarging his conceptions of the wisdom, the energy, and the beneficence of the Great Ruler of the universe

The study of human anatomy is the basis of the investigation of the anatomy of all animals with a back-bone; and conversely, the anatomy of any animal of this class tends to throw light on that of man.

There are no royal roads to knowledge, and we can only advance to new and important truths along the rugged path of experience, guided by cautious induction.

There is poetry in science and the cultivation of the imagination is an essential prerequisite to the successful investigation of nature.