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Home > Dictionary of Science Quotations > Scientist Names Index P > Louis Pasteur Quotes > Experiment

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Louis Pasteur
(27 Dec 1822 - 28 Sep 1895)

French chemist who became a founder of microbiology. He created and tested vaccines for diphtheria, cholera, yellow fever, plague, rabies, anthrax, and tuberculosis.


Louis Pasteur Quotes on Experiment (10 quotes)

>> Click for 66 Science Quotes by Louis Pasteur

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As I show you this liquid, I too could tell you, 'I took my drop of water from the immensity of creation, and I took it filled with that fecund jelly, that is, to use the language of science, full of the elements needed for the development of lower creatures. And then I waited, and I observed, and I asked questions of it, and I asked it to repeat the original act of creation for me; what a sight it would be! But it is silent! It has been silent for several years, ever since I began these experiments. Yes! And it is because I have kept away from it, and am keeping away from it to this moment, the only thing that it has not been given to man to produce, I have kept away from it the germs that are floating in the air, I have kept away from it life, for life is the germ, and the germ is life.'
— Louis Pasteur
Quoted in Patrice Debré, Louis Pasteur, trans. Elborg Forster (1994), 169.
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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
Ésur la maladie des vers ásoie (1870), 39.
Science quotes on:  |  Distinction (37)  |  Error (230)  |  Establish (30)  |  Experiment (543)  |  Fact (609)  |  Observation (418)  |  Rigour (10)  |  Truth (750)

I give them experiments and they respond with speeches.
— Louis Pasteur
in Patrice Debrι, Louis Pasteur, trans. Elborg Forster (1994), 362.
Science quotes on:  |  Experiment (543)  |  Response (24)  |  Speech (40)

In experimental science it’s always a mistake not to doubt when facts do not compel you to affirm.
— Louis Pasteur
…...
Science quotes on:  |  Affirm (2)  |  Compel (14)  |  Doubt (121)  |  Experimental (12)  |  Fact (609)  |  Mistake (107)  |  Science (1699)

It is characteristic of experimental science that it opens ever-widening horizons to our vision.
— Louis Pasteur
As translated in Renι J. Dubos, Louis Pasteur, Free Lance of Science (1950, 1986), 329.
Science quotes on:  |  Characteristic (66)  |  Experiment (543)  |  Horizon (13)  |  Science (1699)

Preconceived ideas are like searchlights which illumine the path of experimenter and serve him as a guide to interrogate nature. They become a danger only if he transforms them into fixed ideas – this is why I should like to see these profound words inscribed on the threshold of all the temples of science: “The greatest derangement of the mind is to believe in something because one wishes it to be so.”
— Louis Pasteur
Speech (8 Jul 1876), to the French Academy of Medicine. As translated in Renι J. Dubos, Louis Pasteur, Free Lance of Science (1950, 1986), 376. Date of speech identified in Maurice B. Strauss, Familiar Medical Quotations (1968), 502.
Science quotes on:  |  Belief (400)  |  Danger (62)  |  Derangement (2)  |  Experimenter (18)  |  Fixed (11)  |  Guide (46)  |  Idea (440)  |  Illuminate (12)  |  Interrogate (3)  |  Mind (544)  |  Nature (1029)  |  Path (59)  |  Preconceive (3)  |  Profound (46)  |  Science (1699)  |  Searchlight (4)  |  Temple (22)  |  Threshold (7)  |  Transform (20)  |  Wish (62)  |  Word (221)

The great art consists in devising dιcisive experiments, leaving no place to the imagination of the observer. Imagination is needed to give wings to thought at the beginning of experimental investigations on any given subject. When, however, the time has come to conclude, and to interpret the facts derived from observations, imagination must submit to the factual results of the experiments.
— Louis Pasteur
Speech (8 Jul 1876), to the French Academy of Medicine. As translated in Renι J. Dubos, Louis Pasteur, Free Lance of Science (1950, 1986), 376. Date of speech identified in Maurice B. Strauss, Familiar Medical Quotations (1968), 502.
Science quotes on:  |  Beginning (114)  |  Conclusion (120)  |  Decisive (9)  |  Derived (5)  |  Devise (11)  |  Experiment (543)  |  Fact (609)  |  Imagination (209)  |  Interpret (15)  |  Investigation (123)  |  Observation (418)  |  Observer (33)  |  Result (250)  |  Subject (129)  |  Submit (12)  |  Thought (374)

This marvellous experimental method eliminates certain facts, brings forth others, interrogates nature, compels it to reply and stops only when the mind is fully satisfied. The charm of our studies, the enchantment of science, is that, everywhere and always, we can give the justification of our principles and the proof of our discoveries.
— Louis Pasteur
As quoted in Renι Dubos, Louis Pasteur, Free Lance of Science (1960, 1986), 377.
Science quotes on:  |  Charm (18)  |  Discovery (591)  |  Enchantment (8)  |  Experiment (543)  |  Fact (609)  |  Interrogate (3)  |  Justification (33)  |  Marvellous (5)  |  Nature (1029)  |  Principle (228)  |  Proof (192)  |  Science (1699)  |  Scientific Method (155)  |  Study (331)

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. Sιdillot) to the method of cultivation out of the body.
— Louis Pasteur
Paper read to the French Academy of Sciences (29 Apr 1878), published in Comptes Rendus de l'Academie des Sciences, 86, 1037-43, as translated by H.C.Ernst. Collected in Charles W. Eliot (ed.) The Harvard Classics, Vol. 38; Scientific Papers: Physiology, Medicine, Surgery, Geology (1910), 364.
Science quotes on:  |  Agent (27)  |  Body (193)  |  Cause (231)  |  Contagion (4)  |  Cultivation (23)  |  Demonstration (51)  |  Disease (257)  |  Experiment (543)  |  Introduce (27)  |  Knowledge (1128)  |  Method (154)  |  Microbe (17)  |  Microscopic (10)  |  Nomenclature (129)  |  Organism (126)  |  Present (103)

When you believe you have found an important scientific fact, and are feverishly curious to publish it, constrain yourself for days, weeks, years sometimes, fight yourself, try and ruin your own experiments, and only proclaim your discovery after having exhausted all contrary hypotheses. But when, after so many efforts you have at last arrived at a certainty, your joy is one of the greatest which can be felt by a human soul.
— Louis Pasteur
From Speech (14 Nov 1888) at the Inauguration of the Pasteur Institute, as translated in Renι Vallery-Radot and Mrs R.L. Devonshire (trans.), The Life of Pasteur (1915), 443.
Science quotes on:  |  Arrive (17)  |  Certainty (97)  |  Constrain (6)  |  Contrary (22)  |  Curious (24)  |  Discovery (591)  |  Effort (94)  |  Exhaust (12)  |  Experiment (543)  |  Fact (609)  |  Greatest (53)  |  Hypothesis (227)  |  Important (124)  |  Joy (61)  |  Proclaim (12)  |  Publish (18)  |  Ruin (23)  |  Science And Journalism (3)  |  Soul (139)


See also:

Carl Sagan Thumbnail In science it often happens that scientists say, 'You know that's a really good argument; my position is mistaken,' and then they would actually change their minds and you never hear that old view from them again. They really do it. It doesn't happen as often as it should, because scientists are human and change is sometimes painful. But it happens every day. I cannot recall the last time something like that happened in politics or religion. (1987) -- Carl Sagan
Quotations by: • Albert Einstein • Isaac Newton • Lord Kelvin • Charles Darwin • Srinivasa Ramanujan • Carl Sagan • Florence Nightingale • Thomas Edison • Aristotle • Marie Curie • Benjamin Franklin • Winston Churchill • Galileo Galilei • Sigmund Freud • Robert Bunsen • Louis Pasteur • Theodore Roosevelt • Abraham Lincoln • Ronald Reagan • Leonardo DaVinci • Michio Kaku • Karl Popper • Johann Goethe • Robert Oppenheimer • Charles Kettering  ... (more people)

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- 90 -
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Euclid
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- 80 -
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Bible
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- 70 -
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- 60 -
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- 50 -
Stephen Hawking
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- 40 -
Pierre Fermat
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JJ Thomson
Thomas Kuhn
Leonardo DaVinci
Archimedes
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- 30 -
Andreas Vesalius
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Richard Feynman
James Hutton
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- 20 -
Carl Sagan
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