TODAY IN SCIENCE HISTORY ®  •  TODAYINSCI ®
Celebrating 24 Years on the Web
Find science on or your birthday

Today in Science History - Quickie Quiz
Who said: “The Superfund legislation... may prove to be as far-reaching and important as any accomplishment of my administration. The reduction of the threat to America's health and safety from thousands of toxic-waste sites will continue to be an urgent�issue �”
more quiz questions >>
Home > Category Index for Science Quotations > Category Index W > Category: Well-Defined

Well-Defined Quotes (9 quotes)

At fertilization, these two “haploid” nuclei are added together to make a “diploid” nucleus that now contains 2a, 2b and so on; and, by the splitting of each chromosome and the regulated karyokinetic separation of the daughter chromosomes, this double series is inherited by both of the primary blastomeres. In the resulting resting nuclei the individual chromosomes are apparently destroyed. But we have the strongest of indications that, in the stroma of the resting nucleus, every one of the chromosomes that enters the nucleus survives as a well-defined region; and as the cell prepares for its next division this region again gives rise to the same chromosome (Theory of the Individuality of the Chromosomes). In this way the two sets of chromosomes brought together at fertilization are inherited by all the cells of the new individual. It is only in the germinal cells that the so called reduction division converts the double series into a single one. Out of the diploid state, the haploid is once again generated.
In Arch. Zellforsch, 1909, 3, 181, trans. Henry Harris, The Birth of the Cell (1999), 171-2.
Science quotes on:  |  Both (496)  |  Call (781)  |  Cell (146)  |  Chromosome (23)  |  Chromosomes (17)  |  Daughter (30)  |  Destroy (189)  |  Division (67)  |  Enter (145)  |  Fertilization (15)  |  Indication (33)  |  Individual (420)  |  Individuality (25)  |  Inherit (35)  |  Inherited (21)  |  New (1273)  |  Next (238)  |  Nucleus (54)  |  Primary (82)  |  Reduction (52)  |  Rise (169)  |  Separation (60)  |  Series (153)  |  Set (400)  |  Single (365)  |  State (505)  |  Strongest (38)  |  Survive (87)  |  Theory (1015)  |  Together (392)  |  Two (936)  |  Way (1214)

Before the promulgation of the periodic law the chemical elements were mere fragmentary incidental facts in nature; there was no special reason to expect the discovery of new elements, and the new ones which were discovered from time to time appeared to be possessed of quite novel properties. The law of periodicity first enabled us to perceive undiscovered elements at a distance which formerly were inaccessible to chemical vision, and long ere they were discovered new elements appeared before our eyes possessed of a number of well-defined properties.
In Faraday Lecture, delivered before the Fellows of the Chemical Society in the Theatre of the Royal Institution (4 Jun 1889), printed in Professor Mendeléeff, 'The Periodic Law of the Chemical Elements', Transactions of the Chemical Society (1889), 55, 648.
Science quotes on:  |  Chemical (303)  |  Discover (571)  |  Discovery (837)  |  Distance (171)  |  Element (322)  |  Expect (203)  |  Expectation (67)  |  Eye (440)  |  Fact (1257)  |  Facts (553)  |  First (1302)  |  Fragmentary (8)  |  Inaccessible (18)  |  Incidental (15)  |  Law (913)  |  Long (778)  |  Nature (2017)  |  New (1273)  |  Novel (35)  |  Number (710)  |  Periodic Law (6)  |  Periodicity (6)  |  Possess (157)  |  Promulgation (5)  |  Property (177)  |  Reason (766)  |  Special (188)  |  Time (1911)  |  Undiscovered (15)  |  Vision (127)

By a generative grammar I mean simply a system of rules that in some explicit and well-defined way assigns structural descriptions to sentences. Obviously, every speaker of a language has mastered and internalized a generative grammar that expresses his knowledge of his language. This is not to say that he is aware of the rules of the grammar or even that he can become aware of them, or that his statements about his intuitive knowledge of the language are necessarily accurate.
Aspects of the Theory of Syntax (1965), 8.
Science quotes on:  |  Accurate (88)  |  Become (821)  |  Knowledge (1647)  |  Language (308)  |  Master (182)  |  Mean (810)  |  Necessarily (137)  |  Rule (307)  |  Say (989)  |  Statement (148)  |  Structural (29)  |  System (545)  |  Way (1214)

He [Heinrich Rose] looked upon the various substances that he was manipulating, as well as their reactions, under a thoroughly familial point of view: they were like so many children entrusted to his tutelage. Every time he explained simple, clear, well-defined phenomena, he assumed a jovial and smiling countenance; on the other hand, he almost got angry at certain mischievous bodies, the properties of which did not obey ordinary laws and troubled general theoretical views; in his eyes, this was unruly behavior.
As his student, about the lectures of Heinrich Rose, as quoted in entry by Stuart Pierson, 'Rose, Heinrich', in Charles Coulston Gillespie (ed.), Dictionary of Scientific Biography (1975), Vol.11, 541, citing Adolphe Remelé, 'Notice biographique sur le Professeur Henri Rose', in Moniteur Scientifique (1864), 2nd ser., 6, 385–389. [Remelé’s italics.]
Science quotes on:  |  Angry (10)  |  Behavior (95)  |  Body (557)  |  Child (333)  |  Clear (111)  |  Countenance (9)  |  Entrust (3)  |  Explain (334)  |  Eye (440)  |  General (521)  |  Law (913)  |  Mischievous (12)  |  Obey (46)  |  On The Other Hand (40)  |  Ordinary (167)  |  Phenomenon (334)  |  Point Of View (85)  |  Property (177)  |  Reaction (106)  |  Simple (426)  |  Smile (34)  |  Substance (253)  |  Theoretical (27)  |  Trouble (117)  |  Tutelage (2)  |  Unruly (4)  |  View (496)

If E is considered to be a continuously divisible quantity, this distribution is possible in infinitely many ways. We consider, however—this is the most essential point of the whole calculation—E to be composed of a well-defined number of equal parts and use thereto the constant of nature h = 6.55 ×10-27 erg sec. This constant multiplied by the common frequency ν of the resonators gives us the energy element ε in erg, and dividing E by ε we get the number P of energy elements which must be divided over the N resonators.
[Planck’s constant, as introduced in 1900; subsequently written e = hν.]
In 'On the theory of the energy distribution law of the normal spectrum', in D. ter Haar and Stephen G. Brush, trans., Planck’s Original Papers in Quantum Physics (1972), 40.
Science quotes on:  |  Calculation (134)  |  Common (447)  |  Consider (428)  |  Constant (148)  |  Definition (238)  |  Distribution (51)  |  Divided (50)  |  Element (322)  |  Energy (373)  |  Equation (138)  |  Essential (210)  |  Frequency (25)  |  Introduce (63)  |  Most (1728)  |  Must (1525)  |  Nature (2017)  |  Number (710)  |  Point (584)  |  Possible (560)  |  Quantity (136)  |  Quantum (118)  |  Use (771)  |  Way (1214)  |  Whole (756)

In the world of human thought generally, and in physical science particularly, the most important and fruitful concepts are those to which it is impossible to attach a well-defined meaning.
In M. Dresen, H. A. Kramers: Between Tradition and Revolution (1987), 539. In Magdolna Hargittai, In Our Own Image (2000), 3.
Science quotes on:  |  Attach (57)  |  Concept (242)  |  Definition (238)  |  Fruitful (61)  |  Human (1512)  |  Important (229)  |  Impossible (263)  |  Meaning (244)  |  Most (1728)  |  Physical (518)  |  Physical Science (104)  |  Thought (995)  |  World (1850)

The chemist works along his own brilliant line of discovery and exposition; the astronomer has his special field to explore; the geologist has a well-defined sphere to occupy. It is manifest, however, that not one of these men can tell the whole tale, and make a complete story of creation. Another man is wanted. A man who, though not necessarily going into formal science, sees the whole idea, and speaks of it in its unity. This man is the theologian. He is not a chemist, an astronomer, a geologist, a botanist——he is more: he speaks of circles, not of segments; of principles, not of facts; of causes and purposes rather than of effects and appearances. Not that the latter are excluded from his study, but that they are so wisely included in it as to be put in their proper places.
In The People's Bible: Discourses Upon Holy Scripture: Vol. 1. Genesis (1885), 120.
Science quotes on:  |  Appearance (145)  |  Astronomer (97)  |  Botanist (25)  |  Brilliant (57)  |  Cause (561)  |  Chemist (169)  |  Circle (117)  |  Complete (209)  |  Creation (350)  |  Discovery (837)  |  Effect (414)  |  Exclusion (16)  |  Exploration (161)  |  Exposition (16)  |  Fact (1257)  |  Facts (553)  |  Field (378)  |  Geologist (82)  |  Idea (881)  |  Inclusion (5)  |  Line (100)  |  Man (2252)  |  More (2558)  |  Necessarily (137)  |  Necessary (370)  |  Place (192)  |  Principle (530)  |  Proper (150)  |  Purpose (336)  |  See (1094)  |  Segment (6)  |  Speak (240)  |  Speaking (118)  |  Special (188)  |  Sphere (118)  |  Story (122)  |  Study (701)  |  Tale (17)  |  Tell (344)  |  Telling (24)  |  Theologian (23)  |  Unity (81)  |  Want (504)  |  Whole (756)  |  Wisedom (2)  |  Work (1402)

The contradictory experiments of chemists leave us at liberty to conclude what we please. My conclusion is, that art has not yet invented sufficient aids to enable such subtle bodies [air, light, &c.] to make a well-defined impression on organs as blunt as ours; that it is laudable to encourage investigation but to hold back conclusion.
Letter to Rev. James Madison (Paris, 19 Jul 1788). In Thomas Jefferson and John P. Foley (ed.), The Jeffersonian Cyclopedia (1900), 135. From H.A. Washington, The Writings of Thomas Jefferson (1853-54). Vol 2, 431.
Science quotes on:  |  Aid (101)  |  Air (366)  |  Art (680)  |  Back (395)  |  Chemist (169)  |  Chemistry (376)  |  Conclude (66)  |  Conclusion (266)  |  Contradiction (69)  |  Enable (122)  |  Encourage (43)  |  Experiment (736)  |  Impression (118)  |  Investigation (250)  |  Light (635)  |  Organ (118)  |  Please (68)  |  Sufficient (133)

We were able to see the plankton blooms resulting from the upwelling off the coast of Chile. The plankton itself extended along the coastline and had some long tenuous arms reaching out to sea. The arms or lines of plankton were pushed around in a random direction, fairly well-defined yet somewhat weak in color, in contrast with the dark blue ocean. The fishing ought to be good down there.
…...
Science quotes on:  |  Arm (82)  |  Arms (37)  |  Bloom (11)  |  Blue (63)  |  Coast (13)  |  Coastline (2)  |  Color (155)  |  Contrast (45)  |  Dark (145)  |  Direction (185)  |  Down (455)  |  Extend (129)  |  Fairly (4)  |  Fish (130)  |  Fishing (20)  |  Good (906)  |  Line (100)  |  Long (778)  |  Ocean (216)  |  Plankton (3)  |  Push (66)  |  Random (42)  |  Reach (286)  |  Result (700)  |  Sea (326)  |  See (1094)  |  Tenuous (3)  |  Weak (73)


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 EinsteinIsaac NewtonLord KelvinCharles DarwinSrinivasa RamanujanCarl SaganFlorence NightingaleThomas EdisonAristotleMarie CurieBenjamin FranklinWinston ChurchillGalileo GalileiSigmund FreudRobert BunsenLouis PasteurTheodore RooseveltAbraham LincolnRonald ReaganLeonardo DaVinciMichio KakuKarl PopperJohann GoetheRobert OppenheimerCharles Kettering  ... (more people)

Quotations about:Atomic  BombBiologyChemistryDeforestationEngineeringAnatomyAstronomyBacteriaBiochemistryBotanyConservationDinosaurEnvironmentFractalGeneticsGeologyHistory of ScienceInventionJupiterKnowledgeLoveMathematicsMeasurementMedicineNatural ResourceOrganic ChemistryPhysicsPhysicianQuantum TheoryResearchScience and ArtTeacherTechnologyUniverseVolcanoVirusWind PowerWomen ScientistsX-RaysYouthZoology  ... (more topics)
Sitewide search within all Today In Science History 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 |
Thank you for sharing.
- 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


by Ian Ellis
who invites your feedback
Thank you for sharing.
Today in Science History
Sign up for Newsletter
with quiz, quotes and more.