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Home > Dictionary of Science Quotations > Scientist Names Index P > Ivan Petrovich Pavlov Quotes

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Ivan Petrovich Pavlov
(27 Sep 1849 - 27 Feb 1936)

Russian physiologist , who was awarded the 1904 Nobel Prize in Physiology or Medicine. He pioneered the investigation that he named the “conditioned reflex.” In his famous experiment, he trained a hungry dog to associate the sound of a bell with receiving food and begin salivating.


Science Quotes by Ivan Petrovich Pavlov (13 quotes)

Essentially only one thing in life interests us: our psychical constitution, the mechanism of which was and is wrapped in darkness. All human resources, art, religion, literature, philosophy and historical sciences, all of them join in bringing lights in this darkness. But man has still another powerful resource: natural science with its strictly objective methods. This science, as we all know, is making huge progress every day. The facts and considerations which I have placed before you at the end of my lecture are one out of numerous attempts to employ a consistent, purely scientific method of thinking in the study of the mechanism of the highest manifestations of life in the dog, the representative of the animal kingdom that is man's best friend.
— Ivan Petrovich Pavlov
'Physiology of Digestion', Nobel Lecture (12 Dec 1904). In Nobel Lectures: Physiology or Medicine 1901-1921 (1967), 134
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I am convinced that an important stage of human thought will have been reached when the physiological and the psychological, the objective and the subjective, are actually united, when the tormenting conflicts or contradictions between my consciousness and my body will have been factually resolved or discarded.
— Ivan Petrovich Pavlov
Physiology of the Higher Nervous Activity (1932), 93-4.
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In gaining knowledge you must accustom yourself to the strictest sequence. You must be familiar with the very groundwork of science before you try to climb the heights. Never start on the “next” before you have mastered the “previous.”
— Ivan Petrovich Pavlov
Translation of a note, 'Bequest of Pavlov to the Academic Youth of his Country', written a few days before his death for a student magazine, The Generation of the Victors. As published in 'Pavlov and the Spirit of Science', Nature (4 Apr 1936), 137, 572.
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In the dog two conditions were found to produce pathological disturbances by functional interference, namely, an unusually acute clashing of the excitatory and inhibitory processes, and the influence of strong and extraordinary stimuli. In man precisely similar conditions constitute the usual causes of nervous and psychic disturbances. Different conditions productive of extreme excitation, such as intense grief or bitter insults, often lead, when the natural reactions are inhibited by the necessary restraint, to profound and prolonged loss of balance in nervous and psychic activity.
— Ivan Petrovich Pavlov
Ivan Pavlov and G. V. Anrep (ed., trans.), Conditioned Reflexes—An Investigation of the Physiological Activity of the Cerebral Cortex (1927), 397.
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Let the mind rise from victory to victory over surrounding nature, let it but conquer for human life and activity not only the surface of the earth but also all that lies between the depth of the sea and the outer limits of the atmosphere; let it command for its service prodigious energy to flow from one part of the universe to the other, let it annihilate space for the transference of its thoughts.
— Ivan Petrovich Pavlov
In Ivan Pavlov and William Horsley Gantt (trans.), Lectures on Conditioned Reflexes (1928, 1941), Preface, 41.
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Modesty. Never think you know all. Though others may flatter you, retain the courage to say, “I am ignorant”.
— Ivan Petrovich Pavlov
Translation of a note, 'Bequest of Pavlov to the Academic Youth of his Country', written a few days before his death for a student magazine, The Generation of the Victors. As published in 'Pavlov and the Spirit of Science', Nature (4 Apr 1936), 137, 572.
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One can truly say that the irresistible progress of natural science since the time of Galileo has made its first halt before the study of the higher parts of the brain, the organ of the most complicated relations of the animal to the external world. And it seems, and not without reason, that now is the really critical moment for natural science; for the brain, in its highest complexity—the human brain—which created and creates natural science, itself becomes the object of this science.
— Ivan Petrovich Pavlov
Natural Science and Brain (1909), 120.
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Only science, exact science about human nature itself, and the most sincere approach to it by the aid of the omnipotent scientific method, will deliver man from his present gloom and will purge him from his contemporary share in the sphere of interhuman relations.
— Ivan Petrovich Pavlov
In Ivan Pavlov and William Horsley Gantt (trans.), Lectures on Conditioned Reflexes (1928, 1941), Preface, 41.
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Perfect as the wing of a bird may be, it will never enable the bird to fly if unsupported by the air. Facts are the air of science. Without them a man of science can never rise. Without them your theories are vain surmises. But while you are studying, observing, experimenting, do not remain content with the surface of things. Do not become a mere recorder of facts, but try to penetrate the mystery of their origin. Seek obstinately for the laws that govern them.
— Ivan Petrovich Pavlov
Translation of a note, 'Bequest of Pavlov to the Academic Youth of his Country', written a few days before his death for a student magazine, The Generation of the Victors. As published in 'Pavlov and the Spirit of Science', Nature (4 Apr 1936), 137, 572.
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Science must be your passion. Remember that science claims a man’s whole life. Had he two lives they would not suffice. Science demands an undivided allegiance from its followers. In your work and in your research there must always be passion.
— Ivan Petrovich Pavlov
Translation of a note, 'Bequest of Pavlov to the Academic Youth of his Country', written a few days before his death for a student magazine, The Generation of the Victors. As published in 'Pavlov and the Spirit of Science', Nature (4 Apr 1936), 137, 572.
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The digestive canal is in its task a complete chemical factory. The raw material passes through a long series of institutions in which it is subjected to certain mechanical and, mainly, chemical processing, and then, through innumerable side-streets, it is brought into the depot of the body. Aside from this basic series of institutions, along which the raw material moves, there is a series of lateral chemical manufactories, which prepare certain reagents for the appropriate processing of the raw material.
— Ivan Petrovich Pavlov
Speech to the Society of Russian Physicians (Dec 1874). as translated in Daniel P. Todes, Pavlov’s Physiology Factory: Experiment, Interpretation, Laboratory Enterprise (2002), 155.
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The nervous system is the most complex and delicate instrument on our planet, by means of which relations, connections are established between the numerous parts of the organism, as well as between the organism, as a highly complex system, and the innumerable, external influences. If the closing and opening of electric current is now regarded as an ordinary technical device, why should there be any objection to the idea that the same principle acts in this wonderful instrument? On this basis the constant connection between the external agent and the response of the organism, which it evokes, can be rightly called an unconditioned reflex, and the temporary connection—a conditioned reflex.
— Ivan Petrovich Pavlov
The Conditioned Reflex (1935), 249.
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We must painfully acknowledge that, precisely because of its great intellectual developments, the best of man's domesticated animals—the dog—most often becomes the victim of physiological experiments. Only dire necessity can lead one to experiment on cats—on such impatient, loud, malicious animals. During chronic experiments, when the animal, having recovered from its operation, is under lengthy observation, the dog is irreplaceable; moreover, it is extremely touching. It is almost a participant in the experiments conducted upon it, greatly facilitating the success of the research by its understanding and compliance.
— Ivan Petrovich Pavlov
'Vivisection' (1893), as translated in Daniel P. Todes, Pavlov’s Physiology Factory: Experiment, Interpretation, Laboratory Enterprise (2002), 123.
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Quotes by others about Ivan Petrovich Pavlov (5)

The dog [in Pavlov’s experiments] does not continue to salivate whenever it hears a bell unless sometimes at least an edible offering accompanies the bell. But there are innumerable instances in human life where a single association, never reinforced, results in the establishment of a life-long dynamic system. An experience associated only once with a bereavement, an accident, or a battle, may become the center of a permanent phobia or complex, not in the least dependent on a recurrence of the original shock.
Personality: A Psychological Interpretation(1938), 199.
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Since Pawlow [Pavlov] and his pupils have succeeded in causing the secretion of saliva in the dog by means of optic and acoustic signals, it no longer seems strange to us that what the philosopher terms an 'idea' is a process which can cause chemical changes in the body.
The Mechanistic Conception of Life (1912), 63.
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Does the name Pavlov ring a bell?
Anonymous
Thomas F. Shubnell, Greatest Jokes of the Century Book 2 (2008), 90.
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Pavlov’s data on the two fundamental antagonistic nervous processes—stimulation and inhibition—and his profound generalizations regarding them, in particular, that these processes are parts of a united whole, that they are in a state of constant conflict and constant transition of the one to the other, and his views on the dominant role they play in the formation of the higher nervous activity—all those belong to the most established natural—scientific validation of the Marxist dialectal method. They are in complete accord with the Leninist concepts on the role of the struggle between opposites in the evolution, the motion of matter.
In E. A. Asratyan, I. P. Pavlov: His Life and Work (1953), 153.
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The truth is, Pavlov’s dog trained Pavlov to ring this bell just before the dog salivated.
Brain Droppings (1998), 187.
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See also:
  • 27 Sep - short biography, births, deaths and events on date of Pavlov's birth.
  • Ivan Pavlov: Exploring the Animal Machine, by Daniel Todes. - book suggestion.
  • Booklist for Ivan Pavlov.

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
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Wilhelm Roentgen
Louis Pasteur
Bertrand Russell
Jean Lamarck
- 70 -
Samuel Morse
John Wheeler
Nicolaus Copernicus
Robert Fulton
Pierre Laplace
Humphry Davy
Thomas Edison
Lord Kelvin
Theodore Roosevelt
Carolus Linnaeus
- 60 -
Francis Galton
Linus Pauling
Immanuel Kant
Martin Fischer
Robert Boyle
Karl Popper
Paul Dirac
Avicenna
James Watson
William Shakespeare
- 50 -
Stephen Hawking
Niels Bohr
Nikola Tesla
Rachel Carson
Max Planck
Henry Adams
Richard Dawkins
Werner Heisenberg
Alfred Wegener
John Dalton
- 40 -
Pierre Fermat
Edward Wilson
Johannes Kepler
Gustave Eiffel
Giordano Bruno
JJ Thomson
Thomas Kuhn
Leonardo DaVinci
Archimedes
David Hume
- 30 -
Andreas Vesalius
Rudolf Virchow
Richard Feynman
James Hutton
Alexander Fleming
Emile Durkheim
Benjamin Franklin
Robert Oppenheimer
Robert Hooke
Charles Kettering
- 20 -
Carl Sagan
James Maxwell
Marie Curie
Rene Descartes
Francis Crick
Hippocrates
Michael Faraday
Srinivasa Ramanujan
Francis Bacon
Galileo Galilei
- 10 -
Aristotle
John Watson
Rosalind Franklin
Michio Kaku
Isaac Asimov
Charles Darwin
Sigmund Freud
Albert Einstein
Florence Nightingale
Isaac Newton


by Ian Ellis
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