It is not every question that deserves an answer. >>
If you would live innocently, seek solitude. >>
Treat your friend as if he might become an enemy. >>
Nothing more detestable does the earth produce than an ungrateful man. >>
Ingratitude is treason to mankind. >>
Too great a hurry to discharge an obligation is a kind of ingratitude. >>
One ungrateful man does an injury to all who stand in need of aid.