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Galileo Galilei

Galileo Galilei Quotes

Physicist

Galileo Galilei, an Italian physicist, astronomer, mathematician, and philosopher, is considered the father of modern science. He was born on February 15, 1564, and died on January 8, 1642. Galileo made significant contributions to the fields of physics, astronomy, mathematics, and philosophy. He discovered the four moons of Jupiter through his telescope, supporting Copernicus' heliocentric model, and proposed the law of free fall and other scientific theories.

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Famous Galileo Galilei Quotes

“The doctrine that the earth is neither the center of the universe nor immovable, but moves even with a daily rotation, is absurd, and both philosophically and theologically false, and at the least an error of faith.”

Earth Moving Religion Universe Errors Doctrine Absurd Center Of The Universe Rotation

Author:Galileo Galilei

“In regard to the philosophers, if they be true philosophers, i.e., lovers of truth, they should not be irritated that the earth moves. Rather, if they realize that they have held a false belief, they should thank those have shown them the truth; and if their opinion stands firm that the earth doesn't move, they will have reason to boast than be angered.”

Ifs Should Reason Earth Moving Belief Realizing Opinion Lovers Regard Philosopher Being True Firm Boast Irritated Stand Firm

Author:Galileo Galilei

“The earth, in fair and grateful exchange, pays back to the moon an illumination similar to that which it receives from her throughout nearly all the darkest gloom of the night.”

Earth Night Pay Moon Fairs Grateful Illumination Gloom

Author:Galileo Galilei

“Alas! Your dear friend and servant Galileo has been for the last month hopelessly blind; so that this heaven, this earth, this universe, which I by my marvelous discoveries and clear demonstrations had enlarged a hundred thousand times beyond the belief of the wise men of bygone ages, henceforward for me is shrunk into such a small space as is filled by my own bodily sensations.”

“For my part I consider the earth very noble and admirable precisely because of the diverse alterations, changes, generations, etc. that occur in it incessantly.”

Earth Generations Noble Etc Diverse Admirable Incessantly Alterations

Book:Dialogue Concerning the Two Chief World Systems, Ptolemaic and Copernican, Second Revised Edition

Source: Dialogue Concerning the Two Chief World Systems, Ptolemaic and Copernican, Second Revised Edition

“If there were as great a scarcity of soil as of jewels or precious metals, there would not be a prince who would not spend a bushel of diamonds and rubies and a cartload of gold just to have enough earth to plant a jasmine in a little pot, or to sow an orange seed and watch it sprout, grow, and produce its handsome leaves, its fragrant flowers, and fine fruit.”

Source: Thus Spoke Galileo: The Great Scientist's Ideas and Their Relevance to the Present Day

“The deeper I go in considering the vanities of popular reasoning, the lighter and more foolish I find them. What greater stupidity can be imagined than that of calling jewels, silver, and gold "precious," and earth and soil "base"?”

Earth Greater Calling Gold Deeper Stupidity Foolish Vanity Reasoning Soil Silver Considering Jewels Lighters

Book:Dialogue Concerning the Two Chief World Systems, Ptolemaic and Copernican, Second Revised Edition

Source: Dialogue Concerning the Two Chief World Systems, Ptolemaic and Copernican, Second Revised Edition

“I have been judged vehemently suspect of heresy, that is, of having held and believed that the sun in the centre of the universe and immoveable, and that the earth is not at the center of same, and that it does move. Wishing however, to remove from the minds of your Eminences and all faithful Christians this vehement suspicion reasonably conceived against me, I abjure with a sincere heart and unfeigned faith, I curse and detest the said errors and heresies, and generally all and every error, heresy, and sect contrary to the Holy Catholic Church. (Quoted in Shea and Artigas 194)”

“E pur si muove. "Albeit It does move". (That's what Galileo purportedly muttered after torturers forced him to recant his theory that the earth orbits the sun.)”

Doe Earth Moving Sun Theory Orbit

Author:Galileo Galilei

“In my studies of astronomy and philosophy I hold this opinion about the universe, that the Sun remains fixed in the centre of the circle of heavenly bodies, without changing its place; and the Earth, turning upon itself, moves round the Sun.”

Philosophy Body Earth Moving Universe Opinion Sun Study Remains Rounds Astronomy Circles Fixed Heavenly Centre Cosmology Heavenly Bodies

Author:Galileo Galilei

“If you could see the earth illuminated when you were in a place as dark as night, it would look to you more splendid than the moon.”

Ifs Looks Earth Night Nature Dark Space Moon Splendid

Book:Thus Spoke Galileo: The Great Scientist's Ideas and Their Relevance to the Present Day

Source: Thus Spoke Galileo: The Great Scientist's Ideas and Their Relevance to the Present Day

“The surface of the Moon is not smooth, uniform, and precisely spherical as a great number of philosophers believe it to be, but is uneven, rough, and full of cavities and prominences, being not unlike the face of the Earth, relieved by chains of mountains and deep valleys.”

Believe Earth Faces Numbers Moon Mountain Philosopher Surface Chains Rough Valleys Uniforms Smooth Relieved Prominence

Book:Men of physics: Galileo Galilei, his life and his works

Source: Men of physics: Galileo Galilei, his life and his works

“When the moon is ninety degrees away from the sun it sees but half the earth illuminated (the western half). For the other (the eastern half) is enveloped in night. Hence the moon itself is illuminated less brightly from the earth, and as a result its secondary light appears fainter to us.”

Light Earth Science Night Results Half Sun Moon Degrees Western Eastern Ninety

Author:Galileo Galilei

“We see only the simple motion of descent, since that other circular one common to the Earth, the tower, and ourselves remains imperceptible. There remains perceptible to us only that of the stone, which is not shared by us; and, because of this, sense shows it as by a straight line, always parallel to the tower, which is built upright and perpendicular upon the terrestrial surface.”

Shows Earth Science Lines Simple Common Built Stones Remains Surface Gravity Towers Parallels Descent Straight Lines

Author:Galileo Galilei

“Take note, theologians, that in your desire to make matters of faith out of propositions relating to the fixity of sun and earth you run the risk of eventually having to condemn as heretics those who would declare the earth to stand still and the sun to change position-eventually, I say, at such a time as it might be physically or logically proved that the earth moves and the sun stands still.”

Stills Matter Might Running Earth Moving Science Desire Religion Sun Risk Position Notes Propositions Theologian Heretic

Book:Dialogue Concerning the Two Chief World Systems, Ptolemaic and Copernican, Second Revised Edition

Source: Dialogue Concerning the Two Chief World Systems, Ptolemaic and Copernican, Second Revised Edition