The advantages of philosophy? That I am able to hold converse with myself.
Quarrels often arise in marriages when the bridal gifts are excessive.
Observe your enemies, for they first find out your faults.
We must not contradict, but instruct him that contradicts us; for a madman is not cured by another running mad also.
Not to unlearn what you have learned is the most necessary kind of learning.
How to get rid of having anything to unlearn.