Nothing occurs contrary to nature except the impossible, and that never occurs.

Names and attributes must be accommodated to the essence of things, and not the essence to the names, since things come first and names afterwards.

I do not know what to say in a case so surprising, so unlooked for and so novel.

Long experience has taught me this about the status of mankind with regard to matters requiring thought: the less people know and understand about them, the more positively they attempt to argue concerning them, while on the other hand to know and understand a multitude of things renders men cautious in passing judgment upon anything new.

To command their professors of astronomy to refute their own observations is to command them not to see what they do see and not to understand what they do understand.

Vision, I say, is related to light itself. But of this sensation and the things pertaining to it, I pretend to understand but little; and since even a long time would not suffice to explain that trifle, or even to hint at an explanation, I pass over this in silence.

Being infinitely amazed, so do I give thanks to God, Who has been pleased to make me the first observer of marvelous things, unrevealed to bygone ages.