Nothing occurs contrary to nature except the impossible, and that never occurs.
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.
I abjure with a sincere heart and unfeigned faith, I curse and detest the said errors and heresies, and generally all and every error and sect contrary to the Holy Catholic Church.
The Milky Way is nothing else but a mass of innumerable stars planted together in clusters.
The hypothesis is pretty; its only fault is that it is neither demonstrated nor demonstrable. Who does not see that this is purely arbitrary fiction that puts nothingness as existing and proposes nothing more than simple noncontradiciton?
You may force me to say what you wish; you may revile me for saying what I do. But it moves.
But some, besides allegiance to their original error, possess I know not what fanciful interest in remaining hostile not so much toward the things in question as toward their discoverer.
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.
Showing a greater fondness for their own opinions than for truth, they sought to deny and disprove the new things which, if they had cared to look for themselves, their own senses would have demonstrated to them.
Some, merely to contradict what I had said, did not scruple to cast doubt upon things they had seen with their own eyes again and again.
With regard to matters requiring thought: the less people know and understand about them, the more positively they attempt to argue concerning them.
See now the power of truth.
If I were again beginning my studies, I would follow the advice of Plato and start with mathematics.
It vexes me when they would constrain science by the authority of the Scriptures, and yet do not consider themselves bound to answer reason and experiment.
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”?
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.
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.
Nature is relentless and unchangeable, and it is indifferent as to whether its hidden reasons and actions are understandable to man or not.
Where the senses fail us, reason must step in.
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.