Man's greatest victory is over oneself.

When you swear, swear seriously and solemnly, but at the same time with a smile, for a smile is the twin sister of seriousness.

The good is the beautiful.

A fit of laughter, which has been indulged to excess, almost always produces a violent reaction.

If a man says that it is right to give every one his due, and therefore thinks within his own mind that injury is due from a just man to his enemies but kindness to his friends, he was not wise who said so, for he spoke not the truth, for in no case has it appeared to be just to injure any one.

Astronomy compels the soul to look upwards and leads us from this world to another.

We will be better men, braver and less idle, if we believe that one must search for the things one does not know, rather than if we believe that it is not possible to find out what we do not know and that we must not look for it.