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Today in Science History - Quickie Quiz
Who said: “I have no satisfaction in formulas unless I feel their arithmetical magnitude.”
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Thumbnail of Carl Sagan (source)
Carl Sagan
(9 Nov 1934 - 20 Dec 1996)

American astronomer, exobiologist and writer remembered for popularizing astronomy and science, especially with his public television series Cosmos. Its accompanying book spent seventy weeks on The New York Times bestseller list. He was an adviser to NASA for the Mariner, Voyager, and Viking unmanned space missions.


Carl Sagan - A Subject Called Chemistry

Illustrated Quote - Large (800 x 600 px)

“Chlorine is a deadly poison gas employed on European battlefields in World War I. Sodium is a corrosive metal which burns upon contact with water. Together they make a placid and unpoisonous material, table salt. Why each of these substances has the properties it does is a subject called chemistry.”
— Carl Sagan
In Broca's Brain: The Romance of Science.)

More Carl Sagan quotes on science >>

The quote above appears as a footnote in a Carl Sagan essay, 'Can We Know the Universe?' It is one of a number of articles previously published in various magazines that were collected in a book titled Broca's Brain. He opens saying:

“Science is a way of thinking much more than it is a body of knowledge. Its goal is to find out how the world works, to seek what regularities there may be, to penetrate the connections of things. … Understanding is a kind of ecstasy.”

Sagan then moves to wonder to what extent really understanding the universe is possible. So to simplify, he asks what can be known about a mere microgram speck of salt. Sagan compares the number of neurons in the brain with the number of atoms in the tiny grain of salt. The essay compares that with the bits of information for the information-carrying capacity of the brain. He proposes that

“To understand such a universe we would need a brain at least as massive as the universe.”

The essay then roams through mention of the Special Theory of Relativity, the ultimate limit of the speed of light, restrictions on the rotational positions of molecules and infrared spectra.

As for chemistry, the quote above is all he wrote, as a parenthetical thought, expressed only as a footnote.

Quoted text from Carl Sagan, Broca's Brain (1979), 13-18. (source)

Carl Sagan quote Advances in medicine and agriculture
A bean farmer checks her crop in Congo. Photo by Neil Palmer (CIAT). CC2.0 (source)

See also:
  • Science Quotes by Carl Sagan.
  • 9 Nov - short biography, births, deaths and events on date of Sagan's birth.
  • Carl Sagan - context of quote A Subject Called Chemistry - Medium image (500 x 350 px)
  • Carl Sagan - context of quote “Advances in medicine and agriculture” - Medium image (500 x 250 px)
  • Carl Sagan - context of quote “Advances in medicine and agriculture” - Large image (800 x 400 px)
  • Carl Sagan: A Life in the Cosmos, by William Poundstone. - book suggestion.
  • Booklist for Carl Sagan.

Nature bears long with those who wrong her. She is patient under abuse. But when abuse has gone too far, when the time of reckoning finally comes, she is equally slow to be appeased and to turn away her wrath. (1882) -- Nathaniel Egleston, who was writing then about deforestation, but speaks equally well about the danger of climate change today.
Carl Sagan Thumbnail Carl Sagan: 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) ...(more by Sagan)

Albert Einstein: I used to wonder how it comes about that the electron is negative. Negative-positive—these are perfectly symmetric in physics. There is no reason whatever to prefer one to the other. Then why is the electron negative? I thought about this for a long time and at last all I could think was “It won the fight!” ...(more by Einstein)

Richard Feynman: It is the facts that matter, not the proofs. Physics can progress without the proofs, but we can't go on without the facts ... if the facts are right, then the proofs are a matter of playing around with the algebra correctly. ...(more by Feynman)
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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- 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



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