As a means of contrast with the sublime, the grotesque is, in our view, the richest source that nature can offer.

Morality is truth in full bloom.

Let us have compassion for those under chastisement. Alas, who are we ourselves? Who am I and who are you? Whence do we come and is it quite certain that we did nothing before we were born? This earth is not without some resemblance to a gaol. Who knows but that man is a victim of divine justice? Look closely at life. It is so constituted that one senses punishment everywhere.

The straight line, a respectable optical illusion which ruins many a man.

A cannonball travels only two thousand miles an hour; light travels two hundred thousand miles a second. Such is the superiority of Jesus Christ over Napoleon.

There is no supernatural, there is only nature. Nature alone exists and contains all. All is. There is the part of nature that we perceive, and the part of nature that we do not perceive. ... If you abandon these facts, beware; charlatans will light upon them, also the imbecile. There is no mean: science, or ignorance. If science does not want these facts, ignorance will take them up. You have refused to enlarge human intelligence, you augment human stupidity. When Laplace withdraws Cagliostro appears.

The book which the reader now holds in his hands, from one end to the other, as a whole and in its details, whatever gaps, exceptions, or weaknesses it may contain, treats of the advance from evil to good, from injustice to justice, from falsity to truth, from darkness to daylight, from blind appetite to conscience, from decay to life, from bestiality to duty, from Hell to Heaven, from limbo to God. Matter itself is the starting-point, and the point of arrival is the soul. Hydra at the beginning, an angel at the end.