Find science on or your birthday

Today in Science History - Quickie Quiz
Who said: “I was going to record talking... the foil was put on; I then shouted 'Mary had a little lamb',... and the machine reproduced it perfectly.”
more quiz questions >>
Home > Category Index for Science Quotations > Category Index A > Category: A Priori

A Priori Quotes (6 quotes)

Among all the occurrences possible in the universe the a priori probability of any particular one of them verges upon zero. Yet the universe exists; particular events must take place in it, the probability of which (before the event) was infinitesimal. At the present time we have no legitimate grounds for either asserting or denying that life got off to but a single start on earth, and that, as a consequence, before it appeared its chances of occurring were next to nil. ... Destiny is written concurrently with the event, not prior to it.
In Jacques Monot and Austryn Wainhouse (trans.), Chance and Necessity: An Essay on the Natural Philosophy of Modern Biology (1971), 145.
Science quotes on:  |  Appear (7)  |  Assert (4)  |  Chance (73)  |  Consequence (42)  |  Deny (7)  |  Destiny (11)  |  Earth (238)  |  Event (45)  |  Exist (13)  |  Infinitesimal (6)  |  Life (439)  |  Occur (8)  |  Occurrence (20)  |  Particular (22)  |  Possible (19)  |  Prior (2)  |  Probability (54)  |  Start (24)  |  Universe (274)  |  Write (21)  |  Zero (8)

Behold the mighty dinosaur,
Famous in prehistoric lore,
Not only for his power and strength
But for his intellectual length.
You will observe by these remains
The creature had two sets of brains—
One in his head (the usual place),
The other at his spinal base.
Thus he could reason 'A priori'
As well as 'A posteriori'.
No problem bothered him a bit
He made both head and tail of it.
So wise was he, so wise and solemn,
Each thought filled just a spinal column.
If one brain found the pressure strong
It passed a few ideas along.
If something slipped his forward mind
'Twas rescued by the one behind.
And if in error he was caught
He had a saving afterthought.
As he thought twice before he spoke
He had no judgment to revoke.
Thus he could think without congestion
Upon both sides of every question.
Oh, gaze upon this model beast
Defunct ten million years at least.
'The Dinosaur: A Poem' (1912). In E. H. Colbert (ed.), The Dinosaur Book (1951), 78.
Science quotes on:  |  Afterthought (3)  |  Bother (2)  |  Brain (105)  |  Congestion (2)  |  Dinosaur (13)  |  Error (150)  |  Gaze (4)  |  Head (18)  |  Idea (220)  |  Intellect (95)  |  Judgment (38)  |  Million (27)  |  Mind (266)  |  Model (31)  |  Problem (178)  |  Question (152)  |  Rescue (2)  |  Solemnity (3)  |  Speaking (29)  |  Spinal Column (2)  |  Spine (2)  |  Tail (4)  |  Thinking (163)  |  Thought (168)  |  Twice (3)  |  Wisdom (87)

Philosophy stands in need of a science which shall determine the possibility, principles, and extent of human knowledge ΰ priori.
Critique of Pure Reason, translated by John Miller Dow Meiklejohn (1899), 4.
Science quotes on:  |  Extent (11)  |  Knowledge (662)  |  Philosophy (128)  |  Possibility (67)  |  Principle (96)

Science has taught us to think the unthinkable. Because when nature is the guide—rather than a priori prejudices, hopes, fears or desires—we are forced out of our comfort zone. One by one, pillars of classical logic have fallen by the wayside as science progressed in the 20th century, from Einstein's realization that measurements of space and time were not absolute but observer-dependent, to quantum mechanics, which not only put fundamental limits on what we can empirically know but also demonstrated that elementary particles and the atoms they form are doing a million seemingly impossible things at once.
In op-ed, 'A Universe Without Purpose', Los Angeles Times (1 Apr 2012).
Science quotes on:  |  20th Century (9)  |  Absolute (32)  |  Atom (164)  |  Classical (7)  |  Dependence (18)  |  Desire (45)  |  Albert Einstein (155)  |  Falling (3)  |  Fear (52)  |  Guide (17)  |  Hope (50)  |  Impossibility (31)  |  Logic (131)  |  Measurement (108)  |  Nature (524)  |  Observer (8)  |  Pillar (2)  |  Prejudice (29)  |  Progress (198)  |  Quantum Mechanics (15)  |  Realization (21)  |  Science (850)  |  Space And Time (4)  |  Teaching (60)  |  Thinking (163)  |  Unthinkable (2)  |  Wayside (2)

The functional validity of a working hypothesis is not a priori certain, because often it is initially based on intuition. However, logical deductions from such a hypothesis provide expectations (so-called prognoses) as to the circumstances under which certain phenomena will appear in nature. Such a postulate or working hypothesis can then be substantiated by additional observations ... The author calls such expectations and additional observations the prognosis-diagnosis method of research. Prognosis in science may be termed the prediction of the future finding of corroborative evidence of certain features or phenomena (diagnostic facts). This method of scientific research builds up and extends the relations between the subject and the object by means of a circuit of inductions and deductions.
In 'The Scientific Character of Geology', The Journal of Geology (Jul 1961), 69, No. 4, 454-5.
Science quotes on:  |  Certainty (59)  |  Circuit (10)  |  Circumstance (25)  |  Deduction (38)  |  Diagnosis (48)  |  Evidence (80)  |  Expectation (24)  |  Functional (4)  |  Future (101)  |  Hypothesis (147)  |  Induction (22)  |  Intuition (25)  |  Logic (131)  |  Object (44)  |  Observation (256)  |  Phenomenon (113)  |  Postulate (20)  |  Prediction (45)  |  Prognosis (2)  |  Relation (33)  |  Research (358)  |  Scientific Method (98)  |  Subject (48)  |  Substantiate (2)  |  Validity (11)  |  Working (11)

The test of a theory is its ability to cope with all the relevant phenomena, not its a priori 'reasonableness'. The latter would have proved a poor guide in the development of science, which often makes progress by its encounter with the totally unexpected and initially extremely puzzling.
'From DAMTP [Department of Applied Mathematics and Theoretical Physics] to Westcott House', Cambridge Review (1981), 103, 61.
Science quotes on:  |  Ability (38)  |  Coping (3)  |  Development (117)  |  Encounter (6)  |  Extreme (17)  |  Guide (17)  |  Latter (2)  |  Phenomenon (113)  |  Poor (15)  |  Progress (198)  |  Proof (133)  |  Puzzle (14)  |  Reasonableness (3)  |  Relevance (9)  |  Science (850)  |  Test (44)  |  Theory (346)  |  Total (13)  |  Unexpected (13)


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)

Quotations about: • Atomic  Bomb • Biology • Chemistry • Deforestation • Engineering • Anatomy • Astronomy • Bacteria • Biochemistry • Botany • Conservation • Dinosaur • Environment • Fractal • Genetics • Geology • History of Science • Invention • Jupiter • Knowledge • Love • Mathematics • Measurement • Medicine • Natural Resource • Organic Chemistry • Physics • Physician • Quantum Theory • Research • Science and Art • Teacher • Technology • Universe • Volcano • Virus • Wind Power • Women Scientists • X-Rays • Youth • Zoology  ... (more topics)
Sitewide search within all Today In Science History pages:
Custom Quotations Search - custom search within only our quotations pages:
Visit our Science and Scientist Quotations index for more Science Quotes from archaeologists, biologists, chemists, geologists, inventors and inventions, mathematicians, physicists, pioneers in medicine, science events and technology.

Names index: | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |

Categories index: | 1 | 2 | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
Author Icon
who invites your feedback

Today in Science History

Most Popular

Thank you for sharing.
Today in Science History
Sign up for Newsletter
with quiz, quotes and more.
- 100 -
Sophie Germain
Gertrude Elion
Ernest Rutherford
James Chadwick
Marcel Proust
William Harvey
Johann Goethe
John Keynes
Carl Gauss
Paul Feyerabend
- 90 -
Antoine Lavoisier
Lise Meitner
Charles Babbage
Ibn Khaldun
Euclid
Ralph Emerson
Robert Bunsen
Frederick Banting
Andre Ampere
Winston Churchill
- 80 -
John Locke
Bronislaw Malinowski
Bible
Thomas Huxley
Alessandro Volta
Erwin Schrodinger
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

New Book


The Simpsons and their Mathematical Secrets,
by Simon Singh

Cleverly embedded in many Simpsons plots are subtle references to mathematics, because the show's brilliant comedy writers with advanced degrees in math or science. Singh offers an entirely new insight into the most successful show in television history.