Dialogue Concerning the Two Chief World Systems Quotes

“After an injunction had been judicially intimated to me by this Holy Office, to the effect that I must altogether abandon the false opinion that the sun is the center of the world and immovable, and that the earth is not the center of the world, and moves, and that I must not hold, defend, or teach in any way whatsoever, verbally or in writing, the said false doctrine, and after it had been notified to me that the said doctrine was contrary to Holy Scripture — I wrote and printed a book in which I discuss this new doctrine already condemned, and adduce arguments of great cogency in its favor, without presenting any solution of these, and for this reason I have been pronounced by the Holy Office to be vehemently suspected of heresy, that is to say, of having held and believed that the Sun is the center of the world and immovable, and that the earth is not the center and moves:

Therefore, desiring to remove from the minds of your Eminences, and of all faithful Christians, this vehement suspicion, justly conceived against me, with sincere heart and unfeigned faith I abjure, curse, and detest the aforesaid errors and heresies, and generally every other error, heresy, and sect whatsoever contrary to the said Holy Church, and I swear that in the future I will never again say or assert, verbally or in writing, anything that might furnish occasion for a similar suspicion regarding me; but that should I know any heretic, or person suspected of heresy, I will denounce him to this Holy Office, or to the Inquisitor or Ordinary of the place where I may be. Further, I swear and promise to fulfill and observe in their integrity all penances that have been, or that shall be, imposed upon me by this Holy Office. And, in the event of my contravening, any of these my promises and oaths, I submit myself to all the pains and penalties imposed and promulgated in the sacred canons and other constitutions, general and particular, against such delinquents.”
― Galileo Galilei, Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican

“To our natural and human reason, I say that these terms ‘large,’ ‘small,’ ‘immense,’ ‘minute,’ etc. are not absolute but relative; the same thing in comparison with various others may be called at one time ‘immense’ and at another ‘imperceptible.”
― Galileo Galilei, Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican

“To apply oneself to great inventions, starting from the smallest beginnings, is no task for ordinary minds; to divine that wonderful arts lie hid behind trivial and childish things is a conception for superhuman talents.”
― Galileo Galilei, Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican

“There is not a single effect in Nature, not even the least that exists, such that the most ingenious theorists can ever arrive at a complete understanding of it. This vain presumption of understanding everything can have no other basis than never understanding anything. For anyone who had experienced just once the perfect understanding of one single thing, and had truly tasted how knowledge is attained, would recognise that of the infinity of other truths he understands nothing.”
― Galileo Galilei, Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican

“I see that you have hitherto been one of that herd who, in order to learn how matters such as this take place, and in order to acquire a knowledge of natural effects, do not exhaust themselves in waking and studying, and mortify themselves with experiments and observations, but retire into their studies and glance through an index and a table of contents to see whether Aristotle has said any thing about them; and, being assured of the true sense of his text, consider that nothing else can be known.”
― Galileo Galilei, Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican

“All inconveniences will be removed as you propound them. Up to this point, only the first and most general reasons have been mentioned which render it not entirely improbable that the daily rotation belongs to the earth rather than to the rest of the universe.”
― Galileo Galilei, Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican

“But surpassing all stupendous inventions, what sublimity of mind was his who dreamed of finding means to communicate his deepest thoughts to any other person, though distant by mighty intervals of place and time! Of talking with those who are in India; of speaking to those who are not yet born and will not be born for a thousand or ten thousand years; and with what facility, by the different arrangements of twenty characters upon a page!”
― Galileo Galilei, Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican

“Nature first made things in
her own way, and then made human reason skillful enough to be able to understand, but
only by hard work, some part of her secrets.”
― Galileo Galilei, Dialogue Concerning the Two Chief World Systems: Ptolemaic and Copernican