(Note of February 19, 2006)
While doing a net search on something else, I came across several Egyptian verses on the virtue of silence.There is one in the "Book of the Dead":
"Speaking and silent, I remain an exact balance"
But today I have found new references:
"Your silence is better than chatter,
speak when you know you have a solution..."
(A declaration of Ptahhotep)
Ptahhotep also declares:
"Speaking is harder than all other work;
He who understands it makes it serve."