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Home > Dictionary of Science Quotations > Scientist Names Index P > Karl Raimund Popper Quotes > Knowledge

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Karl Raimund Popper
(28 Jul 1902 - 17 Sep 1994)

Austrian-British philosopher of science remembered for his writings on theory of scientific method.


Karl Raimund Popper Quotes on Knowledge (5 quotes)

>> Click for 42 Science Quotes by Karl Raimund Popper

>> Click for Karl Raimund Popper Quotes on | Criticism | Falsification | Idea | Refutation | Science | Scientific Method | Test | Theory | Truth |

I think that we shall have to get accustomed to the idea that we must not look upon science as a 'body of knowledge,' but rather as a system of hypotheses; that is to say, as a system of guesses or anticipations which in principle cannot be justified, but with which we work as long as they stand up to tests, and of which we are never justified in saying that we know they are 'true' or 'more or less certain' or even 'probable.'
— Karl Raimund Popper
The Logic of Scientific Discovery (1959), 317.
Science quotes on:  |  Accustom (52)  |  Accustomed (46)  |  Anticipation (18)  |  Body (557)  |  Certain (557)  |  Certainty (180)  |  Guess (67)  |  Hypothesis (314)  |  Idea (881)  |  Justification (52)  |  Know (1538)  |  Knowledge (1647)  |  Long (778)  |  Look (584)  |  More (2558)  |  More Or Less (71)  |  Must (1525)  |  Never (1089)  |  Principle (530)  |  Probability (135)  |  Say (989)  |  Stand (284)  |  System (545)  |  Test (221)  |  Think (1122)  |  Truth (1109)  |  Work (1402)

It is not his possession of knowledge, of irrefutable truth, that makes the man of science, but his persistent and recklessly critical quest for truth.
— Karl Raimund Popper
In The Logic of Scientific Discovery (1959, 1972), 281.
Science quotes on:  |  Critical (73)  |  Irrefutable (5)  |  Knowledge (1647)  |  Man (2252)  |  Persistent (18)  |  Possession (68)  |  Quest (39)  |  Recklessly (2)  |  Truth (1109)

Our knowledge can only be finite, while our ignorance must necessarily be infinite.
— Karl Raimund Popper
Essy, 'On the Sources of Knowledge and of Ignorance', in Conjectures and Refutations: The Growth of Scientific Knowledge (1962), 28.
Science quotes on:  |  Finite (60)  |  Ignorance (254)  |  Infinite (243)  |  Knowledge (1647)  |  Must (1525)  |  Necessarily (137)

The growth of our knowledge is the result of a process closely resembling what Darwin called “natural selection”; that is, the natural selection of hypotheses: our knowledge consists, at every moment, of those hypotheses which have shown their (comparative) fitness by surviving so far in their struggle for existence, a competitive struggle which eliminates those hypotheses which are unfit.
— Karl Raimund Popper
From Objective Knowledge: An Evolutionary Approach (1971), 261. As quoted in Dean Keith Simonton, Origins of Genius: Darwinian Perspectives on Creativity (1999), 26.
Science quotes on:  |  Call (781)  |  Consist (223)  |  Existence (481)  |  Growth (200)  |  Hypothesis (314)  |  Knowledge (1647)  |  Moment (260)  |  Natural (810)  |  Natural Selection (98)  |  Process (439)  |  Result (700)  |  Selection (130)  |  Struggle (111)

The old scientific ideal of episteme — of absolutely certain, demonstrable knowledge — has proved to be an idol. The demand for scientific objectivity makes it inevitable that every scientific statement must remain tentative for ever. (1959)
— Karl Raimund Popper
The Logic of Scientific Discovery: Logik Der Forschung (1959, 2002), 280.
Science quotes on:  |  Certain (557)  |  Certainty (180)  |  Demand (131)  |  Ideal (110)  |  Idol (5)  |  Inevitable (53)  |  Knowledge (1647)  |  Must (1525)  |  Objectivity (17)  |  Old (499)  |  Proof (304)  |  Remain (355)  |  Scientific (955)  |  Statement (148)  |  Tentative (18)  |  Theory (1015)


See also:
  • 28 Jul - short biography, births, deaths and events on date of Popper's birth.

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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Ernest Rutherford
James Chadwick
Marcel Proust
William Harvey
Johann Goethe
John Keynes
Carl Gauss
Paul Feyerabend
- 90 -
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Lise Meitner
Charles Babbage
Ibn Khaldun
Euclid
Ralph Emerson
Robert Bunsen
Frederick Banting
Andre Ampere
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Bible
Thomas Huxley
Alessandro Volta
Erwin Schrodinger
Wilhelm Roentgen
Louis Pasteur
Bertrand Russell
Jean Lamarck
- 70 -
Samuel Morse
John Wheeler
Nicolaus Copernicus
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Thomas Edison
Lord Kelvin
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- 60 -
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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
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