Quotes from Nicolaus Copernicus

At rest, however, in the middle of everything is the sun.

We regard it as a certainty that the earth, enclosed between poles, is bounded by a spherical surface.

Every light has its shadow, and every shadow hath a succeeding morning.

I am aware that a philosopher's ideas are not subject to the judgment of ordinary persons, because it is his endeavour to seek the truth in all things, to the extent permitted to human reason by God.

Pouring forth its seas everywhere, then, the ocean envelops the earth and fills its deeper chasms.

Moreover, since the sun remains stationary, whatever appears as a motion of the sun is really due rather to the motion of the earth.

Accordingly, since nothing prevents the earth from moving, I suggest that we should now consider also whether several motions suit it, so that it can be regarded as one of the planets. For, it is not the center of all the revolutions.

For a traveler going from any place toward the north, that pole of the daily rotation gradually climbs higher, while the opposite pole drops down an equal amount.

In so many and such important ways, then, do the planets bear witness to the earth's mobility.

Therefore, having obtained the opportunity from these sources, I too began to consider the mobility of the earth.

For I am not so enamoured of my own opinions that I disregard what others may think of them.

Those things which I am saying now may be obscure, yet they will be made clearer in their proper place.

For it is the duty of an astronomer to compose the history of the celestial motions through careful and expert study.

The earth together with its surrounding waters must in fact have such a shape as its shadow reveals, for it eclipses the moon with the arc of a perfect circle.

Those 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.

I 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.

Mathematics is written for mathematicians.

The earth also is spherical, since it presses upon its center from every direction.

The massive bulk of the earth does indeed shrink to insignificance in comparison with the size of the heavens.

So 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.

To know that we know what we know, and to know that we do not know what we do not know, that is true knowledge.

I shall now recall to mind that the motion of the heavenly bodies is circular, since the motion appropriate to a sphere is rotation in a circle.

Finally we shall place the Sun himself at the center of the Universe.

Near the sun is the center of the universe.