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Wikipedia Summary for Louis Pasteur

Louis Pasteur (, French: [lwi pastœʁ]; 27 December 1822 – 28 September 1895) was a French chemist and microbiologist renowned for his discoveries of the principles of vaccination, microbial fermentation, and pasteurization. His research in chemistry led to remarkable breakthroughs in the understanding of the causes and preventions of diseases, which laid down the foundations of hygiene, public health and much of modern medicine. His works are credited to saving millions of lives through the developments of vaccines for rabies and anthrax. He is regarded as one of the founders of modern bacteriology and has been honoured as the "father of bacteriology" and as the "father of microbiology" (together with Robert Koch, and the latter epithet also attributed to Antonie van Leeuwenhoek).

Pasteur was responsible for disproving the doctrine of spontaneous generation. Under the auspices of the French Academy of Sciences, his experiment demonstrated that in sterilized and sealed flasks, nothing ever developed; and, conversely, in sterilized but open flasks, microorganisms could grow. For this experiment, the academy awarded him the Alhumbert Prize carrying 2,500 francs in 1862.

Pasteur is also regarded as one of the fathers of germ theory of diseases, which was a minor medical concept at the time. His many experiments showed that diseases could be prevented by killing or stopping germs, thereby directly supporting the germ theory and its application in clinical medicine. He is best known to the general public for his invention of the technique of treating milk and wine to stop bacterial contamination, a process now called pasteurization. Pasteur also made significant discoveries in chemistry, most notably on the molecular basis for the asymmetry of certain crystals and racemization. Early in his career, his investigation of tartaric acid resulted in the first resolution of what is now called optical isomers. His work led the way to the current understanding of a fundamental principle in the structure of organic compounds.

He was the director of the Pasteur Institute, established in 1887, until his death, and his body was interred in a vault beneath the institute. Although Pasteur made groundbreaking experiments, his reputation became associated with various controversies. Historical reassessment of his notebook revealed that he practiced deception to overcome his rivals.

The greatest disorder of the mind is to let will direct it.

--Louis Pasteur

Do not put forward anything that you cannot prove by experimentation.

--Louis Pasteur

Time is the best appraiser of scientific work, and I am aware that an industrial discovery rarely produces all its fruit in the hands of its first inventor.

--Louis Pasteur

The Ancients understood the omnipotence of the underside of things.

--Louis Pasteur

It would seem to me that I was committing a theft if I were to let one day go by without doing some work.

--Louis Pasteur

Science and Peace will triumph over Ignorance and War.

--Louis Pasteur

My strength lies solely in my tenacity.

--Louis Pasteur

To demonstrate experimentally that a microscopic organism actually is the cause of a disease and the agent of contagion, I know no other way, in the present state of Science, than to subject the microbe (the new and happy term introduced by M. Sédillot) to the method of cultivation out of the body.

--Louis Pasteur

The grandeur of the acts of men are measured by the inspiration from which they spring.

--Louis Pasteur

As in the experimental sciences, truth cannot be distinguished from error as long as firm principles have not been established through the rigorous observation of facts.

--Louis Pasteur

We affirm the neutrality of Science ... Science is of no country. ... But if Science has no country, the scientist must keep in mind all that may work towards the glory of his country. In every great scientist will be found a great patriot.

--Louis Pasteur

Change only favours minds that are diligently looking and preparing for discovery.

--Louis Pasteur

Herrmann Pidoux and Armand Trousseau stated 'Disease exists within us, because of us, and through us', Pasteur did not entirely disagree, 'This is true for certain diseases', he wrote cautiously, only to add immediately: 'I do not think that it is true for all of them'.

--Louis Pasteur

It is a matter of fact; I approached without a preconceived idea, too ready to declare, if the experiment had imposed upon me the confession, that there was a spontaneous generation, of
which I am convinced today that those who assure it are blindfolded.

--Louis Pasteur

If perchance you should falter during the journey, a hand would be there to support you. If that should be wanting, God, who alone could take that hand from you, would Himself accomplish its work.

--Louis Pasteur

The greatest malfunction of spirit is to believe things.

--Louis Pasteur

These three things -- work, will, success -- fill human existences. Will opens the door to success, both brilliant and happy. Work passes these doors, and at the end of the journey success comes in to crown one's efforts.

--Louis Pasteur

The more I know, the more nearly is my faith that of the Breton peasant. Could I but know all I would have the faith of a Breton peasant woman.

--Louis Pasteur

Since the most ancient times, all men, and particularly those who endeavored in the practice of medicine, have brought closer together two natural phenomena of capital importance: illness or fever and fermentation.

--Louis Pasteur

Science advances through tentative answers to a series of more and more subtle questions which reach deeper and deeper into the essence of natural phenomena.

--Louis Pasteur

If you suppress laboratories, physical science will be stricken with barrenness and death.

--Louis Pasteur

The nights seem to me too long... I am often scolded by Madame Pasteur, but I tell her I shall lead her to fame.

--Louis Pasteur


Whatever your career may be, do not let yourselves become tainted by a deprecating and barren scepticism.

--Louis Pasteur

After death, life reappears in a different form and with different laws. It is inscribed in the laws of the permanence of life on the surface of the earth and everything that has been a plant and an animal will be destroyed and transformed into a gaseous, volatile and mineral substance.

--Louis Pasteur

Bernard was right. The germ is nothing, the terrain is everything.

--Louis Pasteur

The flavor of wine is like delicate poetry.

--Louis Pasteur

A bottle of wine contains more philosophy than all the books in the world.

--Louis Pasteur

The Greeks bequeathed to us one of the most beautiful words in our language -- the word 'enthusiasm' -- en theos -- a god within. The grandeur of human actions is measured by the inspiration from which they spring. Happy is he who bears a god within, and who obeys it.

--Louis Pasteur

Let me tell you the secret that has led me to my goal: my strength lies solely in my tenacity.

--Louis Pasteur

When I approach a child, he inspires in me two sentiments -- tenderness for what he is and respect for what he may become.

--Louis Pasteur

Chance favors the prepared mind.

--Louis Pasteur

Never will the doctrine of spontaneous generation recover from the mortal blow struck by this simple experiment.

--Louis Pasteur

It is surmounting difficulties that makes heroes.

--Louis Pasteur

There are no such things as applied sciences, only applications of science.

--Louis Pasteur

Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world.

--Louis Pasteur

Longer Version:

Science knows no country, because knowledge belongs to humanity, and is the torch which illuminates the world. Science is the highest personification of the nation because that nation will remain the first which carries the furthest the works of thought and intelligence.


The universe is asymmetric and I am persuaded that life, as it is known to us, is a direct result of the asymmetry of the universe or of its indirect consequences.

--Louis Pasteur

Longer Version:

The universe is asymmetric and I am persuaded that life, as it is known to us, is a direct result of the asymmetry of the universe or of its indirect consequences. The universe is asymmetric.


There does not exist a category of science to which one can give the name applied science. There are science and the applications of science, bound together as the fruit of the tree which bears it.

--Louis Pasteur

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