Justus von Liebig Quotes

I will now direct the attention of scientists to a previously unnoticed cause which brings about the metamorphosis and decomposition phenomena which are usually called decay, putrefaction, rotting, fermentation and moldering. This cause is the ability possessed by a body engaged in decomposition or combination, i.e. in chemical action, to give rise in a body in contact with it the same ability to undergo the same change which it experiences itself.

I have spent some months in England, have seen an awful lot and learned little. England is not a land of science, there is only a widely practised dilettantism, the chemists are ashamed to call themselves chemists because the pharmacists, who are despised, have assumed this name.

If you want to become a chemist, you will have to ruin your health. If you don't ruin your health studying, you won't accomplish anything these days in chemistry. Liebig's advice to Kekulé.

There is in the chemist a form of thought by which all ideas become visible in the mind as strains of an imagined piece of music. This form of thought is developed in Faraday in the highest degree, whence it arises that to one who is not acquainted with this method of thinking, his scientific works seem barren and dry, and merely a series of researches strung together, while his oral discourse when he teaches or explains is intellectual, elegant, and of wonderful clearness.

Chocolate is a perfect food, as wholesome as it is delicious, a beneficent restorer of exhausted power...it is the best friend of those engaged in literary pursuits.

The secret of all those who make discoveries is that they regard nothing as impossible.

Chemistry, in its application to animals and vegetables. Endeavours jointly with physiology to enlighten us respecting the mysterious processes and sources of organic life.

Observation is like a piece of glass, which, as a mirror, must be very smooth, and must be very carefully polished, in order that it may reflect the image pure and undistorted.

I have learnt that all our theories are not Truth itself, but resting places or stages on the way to the conquest of Truth, and that we must be contented to have obtained for the strivers after Truth such a resting place which, if it is on a mountain, permits us to view the provinces already won and those still to be conquered.

The more fodder, the more flesh; the more flesh, the more manure; the more manure, the more grain.

A fact acquires its true and full value only through the idea which is developed from it.

If it is impossible to judge merit and guilt in the field of natural science, then it is not possible in any field, and historical research becomes an idle, empty activity.

A manure containing several ingredients acts in this wise: The effect of all of them in the soil accommodates itself to that one among them which, in comparison to the wants of the plant, is present in the smallest quantity.

Since the discovery of oxygen the civilised world has undergone a revolution in manners and customs. The knowledge of the composition of the atmosphere, of the solid crust of the earth, of water, and of their influence upon the life of plants and animals, was linked to that discovery. The successful pursuit of innumerable trades and manufactures, the profitable separation of metals from their ores, also stand in the closest connection therewith.

But it must not be forgotten that ... glass and porcelain were manufactured, stuffs dyed and metals separated from their ores by mere empirical processes of art, and without the guidance of correct scientific principles.

There are various causes for the generation of force: a tensed spring, an air current, a falling mass of water, fire burning under a boiler, a metal that dissolves in an acid-one and the same effect can be produced by means of all these various causes. But in the animal body we recognise only one cause as the ultimate cause of all generation of force, and that is the reciprocal interaction exerted on one another by the constituents of the food and the oxygen of the air. The only known and ultimate cause of the vital activity in the animal as well as in the plant is a chemical process.

Only about seventy years ago was chemistry, like a grain of seed from a ripe fruit, separated from the other physical sciences. With Black, Cavendish and Priestley, its new era began. Medicine, pharmacy, and the useful arts, had prepared the soil upon which this seed was to germinate and to flourish.

The finest imagination in the world could not have conceived of a better idea than the philosophers' stone to inspire the minds and faculties of men. Without it, chemistry would not be what it is today. In order to discover that no such thing as the philosopher's stone existed, it was necessary to ransack and analyze every substance known on earth. And in precisely this lay its miraculous influence.

What struck me most in England was the perception that only those works which have a practical tendency awake attention and command respect, while the purely scientific, which possess far greater merit are almost unknown. And yet the latter are the proper source from which the others flow. Practice alone can never lead to the discovery of a truth or a principle. In Germany it is quite the contrary. Here in the eyes of scientific men no value, or at least but a trifling one, is placed upon the practical results. The enrichment of science is alone considered worthy attention.

The progress of mankind is due exclusively to the progress of natural sciences, not to morals, religion or philosophy.

From one sublime genius-NEWTON-more light has proceeded than the labour of a thousand years preceding had been able to produce.

In this apparatus is nothing new but its simplicity and thorough trustworthiness. On his revolutionary method of organic analysis.

Receiving a new truth is like adding a new sense.

The loveliest theories are being overthrown by these damned experiments; it's no fun being a chemist anymore.

I would... establish the conviction that Chemistry, as an independent science, offers one of the most powerful means towards the attainment of a higher mental cultivation; that the study of Chemistry is profitable, not only inasmuch as it promotes the material interests of mankind, but also because it furnishes us with insight into those wonders of creation which immediately surround us, and with which our existence, life, and development, are most closely connected.

We may fairly judge of the commercial prosperity of a country from the amount of sulphuric acid it consumes.

A time will come, when fields will be manured with a solution of glass (silicate of potash), with the ashes of burnt straw, and with the salts of phosphoric acid, prepared in chemical manufactories, exactly as at present medicines are given for fever and goitre.

Without an acquaintance with chemistry, the statesman must remain a stranger to the true vital interests of the state, to the means of its organic development and improvement; ... The highest economic or material interests of a country, the increased and more profitable production of food for man and animals, ... are most closely linked with the advancement and diffusion of the natural sciences, especially of chemistry.

By the deficiency or absence of one necessary constituent, all the others being present, the soil is rendered barren for all those crops to the life of which that one constituent is indispensable.

In the progressive growth of astronomy, physics or mechanical science was developed, and when this had been, to a certain degree, successfully cultivated, it gave birth to the science of chemistry.

The person who observes a clock, sees in it not only the pendulum swinging to and fro, and the dial-plate, and the hands moving, for a child can see all this; but he sees also the parts of the clock, and in what connexion the suspended weight stands to the wheel-work, and the pendulum to the moving hands.