"When, therefore, I had long considered the uncertainty of the traditional mathematical doctrines concerning the order of the spheres of the universe, I began to be annoyed that no more accurate explan…"

"For, when a ship is floating calmly on a smooth sea, and the mariners are thinking of nothing but the voyage, if a sudden storm should strike it, and the ship should be driven by the wind, it is not t…"

"For I have found that the motions of the planets are more regular and orderly if the Earth is assumed to move."

"The motion of the celestial bodies is uniform, circular, and perpetual, or composed of circular motions."

"Mathematics is written for mathematicians."