One of our forefathers must have read a forbidden book.

You can make a good living from soothsaying but not from truthsaying.

We have no words for speaking of wisdom to the stupid. He who understands the wise is wise already.

Be attentive, feel nothing in vain, measure and compare: this is the whole law of philosophy.

Doubt everything at least once, even the sentence "Two times two is four."

A man has virtues enough if he deserves pardon for his faults on account of them.

A book is a mirror: if an ape looks into it an apostle is hardly likely to look out.