Louis Pasteur

"Theorie ist die Mutter der Praxis."

"Der Zufall begünstigt den vorbereiteten Geist."

"[…] erinnert an jenen Duellanten, der jeden herausforderte, der es wagte, ihm zu widersprechen oder ihn auch nur scharf anzuschauen, aber der die Gewohnheit hatte, sich die Wahl der Waffen vorzubehalten und seine Gegner verpflichtete, mit gebundenen Händen zu kämpfen."

"I am on the edge of mysteries and the veil is getting thinner and thinner."

"Dans les champs de l'observation le hasard ne favorise que les esprits préparés."

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

"L' univers est dissymetrique..."

"I beseech you to take interest in these sacred domains so expressively called laboratories. Ask that there be more and that they be adorned for these are the temples of the future, wealth and well-being. It is here that humanity will grow, strengthen and improve. Here, humanity will learn to read progress and individual harmony in the works of nature, while humanity's own works are all too often those of barbarism, fanaticism and destruction."

"Posterity will one day laugh at the foolishness of modern materialistic philosophers. The more I study nature, the more I stand amazed at the work of the Creator. I pray while I am engaged at my work in the laboratory."

"Young men, have confidence in those powerful and safe methods, of which we do not yet know all the secrets. And, whatever your career may be, do not let yourselves become tainted by a deprecating and barren scepticism, do not let yourselves be discouraged by the sadness of certain hours which pass over nations. Live in the serene peace of laboratories and libraries. Say to yourselves first : "What have I done for my instruction?" and , as you gradually advance, "What have I done for my country?" until the time comes when you may have the immense happiness of thinking that you have contributed in some way to the progress and to the good of humanity. But, whether our efforts are or not favoured by life, let us be able to say, when we come near the great goal, "I have done what I could.""

"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."

"One does not ask of one who suffers: What is your country and what is your religion? One merely says: You suffer, that is enough for me..."

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

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

"Le premier regard de l'homme jeté sur l'univers n'y découvre que variété, diversité, multiplicité des phénomènes. Que ce regard soit illuminé par la science, — par la science qui rapproche l'homme de Dieu, — et la simplicité et l'unité brillent de toutes parts."

"La génération spontanée, je la cherche sans la découvrir depuis vingt ans. Non, je ne la juge pas impossible. Mais quoi donc vous autorise à vouloir qu'elle ait été l'origine de la vie? Vous placez la matière avant la vie et vous faites la matière existante de toute éternité. Qui vous dit que, le progrès incessant de la science n'obligera pas les savants, qui vivront dans un siècle, dans mille ans, dans dix mille ans... à affirmer que la vie a été de toute éternité et non la matière.? Vous passez de la matière à la vie parce que votre intelligence actuelle, si bornée par rapport à ce que sera l'intelligence des naturalistes futurs, vous dit qu'elle ne peut comprendre autrement les choses. Qui m'assure que dans dix mille ans on ne considérera pas que c'est de la vie qu'on croira impossible de ne pas passer à la matière? Si vous voulez être au nombre des esprits scientifiques, s, qui seuls comptent, il faut vous débarrasser des idées et des raisonnements a priori et vous en tenir aux déductions nécessaires des faits établis et ne pas accorder plus de confiance qu'il ne faut aux déductions de pures hypothèses.""

"Great problems are now being handled, keeping every thinking man in suspense; the unity or multiplicity of human races; the creation of man 1,000 years or 1,000 centuries ago; the fixity of species, or the slow and progressive transformation of one species into another; the eternity of matter; the idea of a God unnecessary: such are some of the questions that humanity discusses nowadays."

"Comprenez-vous maintenant le lien qui existe entre la question des générations spontanées et ces grands problèmes que j'ai énumérés en commençant? Mais, messieurs, dans un pareil sujet, assez de poésie comme cela, assez de fantaisie et de solutions instinctives; il est temps que la science, la vraie méthode reprenne ses droits et les exerce. Il n'y a ici ni religion, ni philosophie, ni athéisme, ni matérialisme, ni spiritualisme qui tienne. Je pourrais même ajouter : Comme savant, peu m'importe. C'est une question de fait; je l'ai abordée sans idée préconçue, aussi prêt à déclarer, si l'expérience m'en avait imposé l'aveu, qu'il existe des générations spontanées, que je suis persuadé aujourd'hui que ceux qui les affirment ont un bandeau sur les veux."

"Et par conséquent, messieurs pourrais-je dire, en vous montrant ce liquide : J’ai pris dans l’immensité de la création ma goutte d’eau, et je l’ai prise toute pleine de la gelée féconde, c’est-à-dire, pour parler le langage de la science, toute pleine des éléments appropriés au développement des êtres inférieurs, Et j’attends, et j’observe, et je l’interroge, et je lui demande de vouloir bien recommencer pour moi la primitive création ; ce serait un si beau spectacle ! Mais elle est muette ! Elle est muette depuis plusieurs années que ces expériences sont commencées. Ah ! c’est que j’ai éloigné d’elle, et que j’éloigne encore en ce moment, la seule chose qu’il n’ait pas été donné à l’homme de produire, j’ai éloigné d’elle les germes qui flottent dans l’ait" j’ai éloigné d’elle la vie, car la vie c’est le germe et le germe c’est la vie. Jamais la doctrine de la génération spontanée ne se relèvera du coup mortel que Cette simple expérience lui porte."

"No, there is now no circumstance known in which it can be affirmed that microscopic beings came into the world without germs, without parents similar to themselves. Those who affirm it have been duped by illusions, by ill-conducted experiments, spoilt by errors that they either did not perceive or did not know how to avoid."

"Maintenant, messieurs, il y aurait un beau sujet à traiter : c’est celui du rôle, dans l’économie générale de la création, de quelques-uns de ces petits êtres qui sont les agents de la fermentation, les agents de la putréfaction, de la désorganisation de tout ce qui a eu vie il la surface du globe. Ce rôle est immense, merveilleux, vraiment émouvant. Un jour peut-être me sera-t-il donné de vous exposer ici quelques-uns de ces résultats. Dieu veuille que ce soit encore en présence à une aussi brillante assemblée!"

"To prove that, until this very day, life has never been shown to man as a product of the forces that govern matter, it could be useful the spiritual doctrine which has been very neglected elsewhere, but always finds at least a glorious refuge in your groups. Perhaps you know that in this difficult question concerning the origin of the infinitesimal, I will have brought experimental rigor that has grown weary of contradiction. Referring to the merit, however, we have inherited severe rules of the method from the great experimenters: Galileo, Pascal, Newton and their followers for two centuries."

"The human spirit, driven by an invincible force, will never cease to ask: What is beyond? Does he want to stop either in time or in space? Since the point at which he has reigned is only a finite magnitude, greater only than all those who have preceded him, he has scarcely begun to think of it as the implacable question and always without being able to silence his curiosity. There is nothing to answer: there are spaces, times or magnitudes without limits. No one understands these words."

"He who proclaims the existence of the Infinite, and none can avoid it — accumulates in that affirmation more of the supernatural than is to be found in all the miracles of all the religions; for the notion of the Infinite presents that double character that forces itself upon us and yet is incomprehensible. When this notion seizes upon our understanding we can but kneel ... I see everywhere the inevitable expression of the Infinite in the world; through it the supernatural is at the bottom of every heart. The idea of God is a form of the idea of the Infinite. As long as the mystery of the infinite weighs on human thought, temples will be erected for the worship of the Infinite, whether God is called Brahma, Allah, Jehovah, or Jesus; and on the pavement of these temples, men will be seen kneeling, prostrated, annihilated by the thought of the Infinite."

"Où sont les vraies sources de la dignité humaine, de la liberté et de la démocratie moderne, sinon dans la notion de l’infini devant laquelle tous les hommes sont égaux?"

"Les Grecs avaient compris la mystérieuse puissance de ce dessous de choses. Ce sont eux qui nous ont légué un des plus beaux mots de notre langue, le mot enthousiasme. — Εν Θεος. — Un Dieu intérieur."

"La grandeur des actions humaines se mesure à l’inspiration qui les fait naître. Heureux celui qui porte en soi un Dieu, un idéal de la beauté et qui lui obéit : idéal de l’art, idéal de la science, idéal de la patrie, idéal des vertus de l’Évangile! Ce sont là les sources vives des grandes pensées et des grandes actions. Toutes s’éclairent des reflets de l’infini."

"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."

"Though one discovery always surpasses another, and though the chemical and physical knowledge accumulated since his time has gone beyond all Lavoisier's dreams, his work, like that of Newton and a few other rare spirits, will remain ever young. Certain details will age, as do the fashions of another time, but the foundation, the method, constitute one of those great aspects of the human mind, the majesty of which is only increased by years."

"God grant that by my persevering labours I may bring a little stone to the frail and ill-assured edifice of our knowledge of those deep mysteries of Life and Death where all our intellects have so lamentably failed."

"I confess frankly, however, that I am not competent on the question of our philosophical schools. Of M. Comte I have only read a few absurd passages; of M. Littré I only know the beautiful pages you were inspired to write by his rare knowledge and some of his domestic virtues. My philosophy is of the heart and not of the mind, and I give myself up, for instance, to those feelings about eternity which come naturally at the bedside of a cherished child drawing its last breath. At those supreme moments, there is something in the depths of our souls which tells us that the world may be more than a mere combination of phenomena proper to a mechanical equilibrium brought out of the chaos of the elements simply through the gradual action of the forces of matter."

"You say that, in the present state of science, it is wiser to have no opinion: well, I have an opinion, not a sentimental one, but a rational one, having acquired a right to it by twenty years of assiduous labour, and it would be wise in every impartial mind to share it. My opinion — nay more, my conviction — is that, in the present state of science, as you rightly say, spontaneous generation is a chimera ; and it would be impossible for you to contradict me, for my experiments all stand forth to prove that spontaneous generation is a chimera. What is then your judgment on my experiments? Have I not a hundred times placed organic matter in contact with pure air in the best conditions for it to produce life spontaneously? Have I not practised on these organic materia which are most favourable, according to all accounts, to the genesis of spontaneity, such as blood, urine, and grape juice? How is it that you do not see the essential difference between my opponents and myself? Not only have I contradicted, proof in hand, every one of their assertions, while they have never dared to seriously contradict one of mine, but, for them, every cause of error benefits their opinion. For me, affirming as I do that there are no spontaneous fermentations, I am bound to eliminate every cause of error, every perturbing influence, I can maintain my results only by means of most irreproachable experiments; their opinions, on the contrary, profit by every insufficient experiment and that is where they find their support."

"You bring me the deepest joy that can be felt by a man whose invincible belief is that Science and Peace will triumph over Ignorance and War, that nations will unite, not to destroy, but to build, and that the future will belong to those who will have done most for suffering humanity."

"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."

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

"Religion has no more place in science than science has in religion."

"It is surmounting difficulties that makes heroes."

"A little science estranges men from God, but much science leads them back to Him."

"The microbe is nothing. The terrain is everything."

"In September 1873 the Germans, who had been occupying sixteen départements, finally left the country. Showing remarkable resilience, the French had discharged the entire five-billion-franc indemnity in a little more than two years. These reparations had been paid so promptly thanks largely to the profits from a booming wine industry, since Louis Pasteur had discovered that pasteurizing wine — briefly heating it to fifty-five degrees Celsius to kill off the microscopic organisms — made it last longer and travel better. The result was an increase in exports to countries such as Britain and America. French art as well as French wine looked like it was beginning to travel well."

"Pasteur originally conceived the idea of germs and of destroying them. Although this started as a personal thing, it has mushroomed into DDT, killing beetles and worms, resulting in food contamination, much sickness, and trouble. Although he is regarded as hero by modern medicine, Pasteur will be treated in much the same way as a warmonger when he is judged in the spiritual world."

"Pasteur was far ahead of his time. Although the structural theory of Kekulé had not yet been proposed, Pasteur explained his results by speaking of the molecules themselves, saying, “There is no doubt that [in the dextro tartaric acid] there exists an asymmetric arrangement having a nonsuperimposable image. It is no less certain that the atoms of the levo acid have precisely the inverse asymmetric arrangement.” Pasteur's vision was extraordinary, for it was not until 25 years later that his ideas regarding the asymmetric carbon atom were confirmed. Today, we would describe Pasteur's work by saying that he had discovered enantiomers. Enantiomers, also called optical isomers, have identical physical properties, such as melting point and boiling point, but differ in the direction in which their solutions rotate plane-polarized light."