Nicolaus Copernicus

The Earth also is not without a certain motion.

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

To know the mighty works of God, to comprehend His wisdom and majesty and power; to appreciate, in degree, the wonderful workings of His laws, surely all this must be a pleasing and acceptable mode of worship to the Most High, to whom ignorance cannot be more pleasing than knowledge.

Yet because the novelty of the undertaking, which I knew to be contrary to the accepted views of the common people, might be regarded as absurd, I long hesitated.

Indeed, I am aware that a philosopher's thoughts are far removed from the judgment of the multitude, for his aim is to seek the truth in all things, to the extent permitted to human reason by God.

For it is the duty of an astronomer to compose the history of the celestial motions from a careful and skillful study of the observations.

For the universe, wrought for us by a supremely good and orderly Creator, is from the very start constructed with the very best and most beautiful design.

The celestial sphere is finite and spherical.

It is not the earth that is the center of the universe, but the sun.

The earth, too, has other motions than that of the daily rotation.

Therefore, when I perceived that these and similar doubts arose concerning the order of the parts of the universe and the symmetry of its structure, I began to be vexed that no more definite explanation of the movements of the world machine, created for our sake by the best and most orderly Workman of all, existed among the philosophers.

In the middle of all sits the Sun enthroned. In this most beautiful temple, could we place this luminary in any better position from which he can illuminate the whole at once?

For the motion of the earth is a fact, and the apparent change of position of the fixed stars is due to the earth's motion and not to any motion of the stars themselves.

Thus, the sun, although it is the center of the world, is not the center of the universe.

Therefore, I think that the earth is not the center of the universe, but rather the sun.

It is clear that the earth also moves in a similar manner, and describes an annual course.

The sphere of the fixed stars is immovable and embraces all things.

For among these, the first and chief consideration is the size of the sphere of the fixed stars, which is immense, and the next is the size of the earth, which is as a point in comparison with the heavens.

Therefore, if any motions are attributed to the earth, they must produce in the celestial phenomena an appearance exactly the reverse of that which is observed.

The world is spherical; whether it is finite or infinite is an open question.