All human actions have one or more of these seven causes: chance, nature, compulsions, habit, reason, passion and desire.
Dignity does not consist in possessing honours, but in deserving them.
Adventure is worthwhile.
Humor is the only test of gravity, and gravity of humor; for a subject which will not bear raillery is suspicious, and a jest which will not bear serious examination is false wit.
No great genius has ever existed without some touch of madness.
Those that know, do. Those that understand, teach.
The greatest virtues are those which are most useful to other persons.
Anyone can become angry - that is easy, but to be angry with the right person at the right time, and for the right purpose and in the right way - that is not within everyone's power and that is not easy.
All proofs rest on premises
I count him braver who overcomes his desires than him who conquers his enemies; for the hardest victory is over self.