We are seldom right to consider ourselves offended by things said about us in our absence or with no intention that they should come to our ears. Because if we try to remember and examine carefully our own habits, we find we have no friend so dear, and hold no one in such veneration, that it would not greatly displease them to hear many of the words and the conversations which come from our mouths about them in their absence. On the one hand our amour propre is so excessively sensitive, and so captious, that it is almost impossible than one word said about us in our absence, if it is faithfully reported to us, should not seem to us unworthy ou hardly worthy of us, and not sting us. On the other hand it is hard to exaggerate how contrary our practice is to the precept not to do unto others what we would not want them to do unto us, and how much freedom we allow ourselves in speaking about other people.
Giacomo Leopardi, in 'Thoughts'