For it is the duty of an astronomer to compose the history of the celestial motions through careful and expert study.
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.
Mathematics is written for mathematicians.
Pouring forth its seas everywhere, then, the ocean envelops the earth and fills its deeper chasms.
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.
