Nicolaus Copernicus
We regard it as a certainty that the earth, enclosed between poles, is bounded by a spherical surface.
Nicolaus CopernicusFinally we shall place the Sun himself at the center of the Universe.
Nicolaus CopernicusYet if anyone believes that the earth rotates, surely he will hold that its motion is natural, not violent.
Nicolaus CopernicusMathematics is written for mathematicians.
Nicolaus CopernicusFirst of all, we must note that the universe is spherical.
Nicolaus CopernicusI CAN easily conceive, most Holy Father, that as soon as some people learn that in this book which I have written concerning the revolutions of the heavenly bodies, I ascribe certain motions to the Earth, they will cry out at once that I and my theory should be rejected.
Nicolaus CopernicusFor I am not so enamoured of my own opinions that I disregard what others may think of them.
Nicolaus CopernicusNear the sun is the center of the universe.
Nicolaus CopernicusMore stars in the north are seen not to set, while in the south certain stars are no longer seen to rise.
Nicolaus CopernicusOf all things visible, the highest is the heaven of the fixed stars.
Nicolaus CopernicusTherefore, when I considered this carefully, the contempt which I had to fear because of the novelty and apparent absurdity of my view, nearly induced me to abandon utterly the work I had begun.
Nicolaus CopernicusEvery observed change of place is caused by a motion of either the observed object or the observer or, of course, by an unequal displacement of each.
Nicolaus CopernicusThose who know that the consensus of many centuries has sanctioned the conception that the earth remains at rest in the middle of the heavens as its center, would, I reflected, regard it as an insane pronouncement if I made the opposite assertion that the earth moves.
Nicolaus CopernicusThe earth also is spherical, since it presses upon its center from every direction.
Nicolaus CopernicusTherefore, having obtained the opportunity from these sources, I too began to consider the mobility of the earth.
Nicolaus CopernicusSo far as hypotheses are concerned, let no one expect anything certain from astronomy, which cannot furnish it, lest he accept as the truth ideas conceived for another purpose, and depart from this study a greater fool than when he entered it.
Nicolaus CopernicusThose things which I am saying now may be obscure, yet they will be made clearer in their proper place.
Nicolaus CopernicusSo, influenced by these advisors and this hope, I have at length allowed my friends to publish the work, as they had long besought me to do.
Nicolaus Copernicus