Galileo di Vincenzo Bonaulti de Galilei was an Italian astronomer, physicist and engineer, sometimes described as a polymath, from Pisa. Galileo has been called the “father of observational astronomy”, the “father of modern physics”, the “father of the scientific method”, and the “father of modern science”.
Galileo studied speed and velocity, gravity and free fall, the principle of relativity, inertia, projectile motion and also worked in applied science and technology, describing the properties of pendulums and “hydrostatic balances”, inventing the thermoscope and various military compasses, and using the telescope for scientific observations of celestial objects.
His contributions to observational astronomy include the telescopic confirmation of the phases of Venus, the observation of the four largest satellites of Jupiter, the observation of Saturn’s rings, and the analysis of sunspots. Galileo’s championing of heliocentrism and Copernicanism was controversial during his lifetime, when most subscribed to geocentric models such as the Tychonic system.
Some of the best quotes from Galileo Galilei are listed below.
- “All truths are easy to understand once they are discovered; the point is to discover them.” – Galileo Galilei
- “And who can doubt that it will lead to the worst disorders when minds created free by God are compelled to submit slavishly to an outside will? When we are told to deny our senses and subject them to the whim of others? When people devoid of whatsoever competence are made judges over experts and are granted authority to treat them as they please? These are the novelties which are apt to bring about the ruin of commonwealths and the subversion of the state.” – Galileo Galilei
- “And, believe me, if I were again beginning my studies, I should follow the advice of Plato and start with mathematics.” – Galileo Galilei
- “By denying scientific principles, one may maintain any paradox.” – Galileo Galilei
- “God is known by nature in his works, and by doctrine in his revealed word.” – Galileo Galilei
- “Holy Scripture could never lie or err…its decrees are of absolute and inviolable truth.” – Galileo Galilei
- “I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use.” – Galileo Galilei
- “I do not think it is necessary to believe that the same God who has given us our senses, reason, and intelligence wished us to abandon their use, giving us by some other means the information that we could gain through them.” – Galileo Galilei
- “I have never met a man so ignorant that I couldn’t learn something from him.” – Galileo Galilei
- “I think that in the discussion of natural problems we ought to begin not with the Scriptures, but with experiments and demonstrations.” – 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.” – Galileo Galilei
- “In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual.” – 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.” – Galileo Galilei
- “In the future, there will be opened a gateway and a road to a large and excellent science into which minds more piercing than mine shall penetrate to recesses still deeper.” – Galileo Galilei
- “In the long run my observations have convinced me that some men, reasoning preposterously, first establish some conclusion in their minds which, either because of its being their own or because of their having received it from some person who has their entire confidence, impresses them so deeply that one finds it impossible ever to get it out of their heads.” – Galileo Galilei
- “In the sciences, the authority of thousands of opinions is not worth as much as one tiny spark of reason in an individual man.” – Galileo Galilei
- “It is a beautiful and delightful sight to behold the body of the Moon.” – Galileo Galilei
- “It is surely harmful to souls to make it a heresy to believe what is proved.” – Galileo Galilei
- “It seems to me that it was well said by Madama Serenissima, and insisted on by your reverence, that the Holy Scripture cannot err, and that the decrees therein contained are absolutely true and inviolable. But I should have in your place added that, though Scripture cannot err, its expounders and interpreters are liable to err in many ways; and one error in particular would be most grave and most frequent, if we always stopped short at the literal signification of the words.” – Galileo Galilei
- “Knowing thyself, that is the greatest wisdom.” – Galileo Galilei
- “Long experience has taught me this about the status of mankind with regard to matters requiring thought: the less people know and understand about them, the more positively they attempt to argue concerning them, while on the other hand to know and understand a multitude of things renders men cautious in passing judgment upon anything new.” – Galileo Galilei
- “Mathematics is the key and door to the sciences.” – Galileo Galilei
- “Mathematics is the language in which God has written the universe” – Galileo Galilei
- “Measure what can be measured, and make measurable what cannot be measured.” – Galileo Galilei
- “Names and attributes must be accommodated to the essence of things, and not the essence to the names, since things come first and names afterwards.” – Galileo Galilei
- “Nature is relentless and unchangeable, and it is indifferent as to whether its hidden reasons and actions are understandable to man or not.” – Galileo Galilei
- “Nature…does not act by means of many things when it can do so by means of a few.” – Galileo Galilei
- “Nonetheless, it moves.” – Galileo Galilei
- “Nothing occurs contrary to nature except the impossible, and that never occurs.” – Galileo Galilei
- “Passion is the genesis of genius.” – Galileo Galilei
- “Philosophy is written in that great book which ever lies before our eyes – I mean the universe – but we cannot understand it if we do not first learn the language and grasp the symbols, in which it is written” – Galileo Galilei
- “Scripture is a book about going to Heaven. It’s not a book about how the heavens go.” – Galileo Galilei
- “See now the power of truth; the same experiment which at first glance seemed to show one thing, when more carefully examined, assures us of the contrary.” – Galileo Galilei
- “Surely, God could have caused birds to fly with their bones made of solid gold, with their veins full of quicksilver, with their flesh heavier than lead, and with their wings exceedingly small. He did not, and that ought to show something. It is only in order to shield your ignorance that you put the Lord at every turn to the refuge of a miracle.” – Galileo Galilei
- “The Bible shows the way to go to heaven, not the way the heavens go.” – Galileo Galilei
- “The book of nature is written in the language of mathematics.” – Galileo Galilei
- “The greatest wisdom is to get to know oneself.” – Galileo Galilei
- “The greatness and the glory of God shine forth marvelously in all His works, and is to be read above all in the open book of the heavens.” – Galileo Galilei
- “The laws of nature are written by the hand of God in the language of mathematics.” – Galileo Galilei
- “The number of people that can reason well is much smaller than those that can reason badly. If reasoning were like hauling rocks, then several reasoners might be better than one. But reasoning isn’t like hauling rocks, it’s like, it’s like racing, where a single, galloping Barbary steed easily outruns a hundred wagon-pulling horses.” – Galileo Galilei
- “The prohibition of science would be contrary to the Bible, which in hundreds of places teaches us how the greatness and the glory of God shine forth marvelously in all His works, and is to be read above all in the open book of the heavens.” – Galileo Galilei
- “The sun, with all those planets revolving around it and dependent on it, can still ripen a bunch of grapes as if it had nothing else in the universe to do.” – Galileo Galilei
- “The vain presumption of understanding everything can have no other basis than never having understood anything. For anyone who had ever experienced just once the perfect understanding of one single thing, and had truly tasted how knowledge is accomplished, would recognize that of the infinity of other truths he understands nothing.” – Galileo Galilei
- “There are those who reason well, but they are greatly outnumbered by those who reason badly.” – Galileo Galilei
- “They seemed to forget that the increase of known truths stimulates the investigation, establishment and growth of the arts; not their dimination or destruction.” – Galileo Galilei
- “To be humane, we must ever be ready to pronounce that wise, ingenious and modest statement ‘I do not know’.” – Galileo Galilei
- “To me, a great ineptitude exists on the part of those who would have it that God made the universe more in proportion to the small capacity of their reason than to His immense, His infinite, power.” – Galileo Galilei
- “To understand the Universe, you must understand the language in which it’s written, the language of Mathematics.” – Galileo Galilei
- “Two truths cannot contradict one another.” – Galileo Galilei
- “We cannot teach people anything; we can only help them discover it within themselves.” – Galileo Galilei
- “Where the senses fail us, reason must step in.” – Galileo Galilei
- “Who indeed will set bounds to human ingenuity? Who will assert that everything in the universe capable of being perceived is already discovered and known?” – Galileo Galilei
- “Wine is sunlight, held together by water.” – Galileo Galilei
- “With regard to matters requiring thought: the less people know and understand about them, the more positively they attempt to argue concerning them.” – Galileo Galilei
- “You cannot teach a man anything, you can only help him find it within himself.” – Galileo Galilei
- “You can’t teach anybody anything, only make them realize the answers are already inside them.” – Galileo Galilei
- “You may force me to say what you wish; you may revile me for saying what I do. But it moves.” – Galileo Galilei