Courtesy that is all on one side cannot last long.
More French Proverbs:
A mad dog cannot live long.French
Hares are not caught by the sound of the drum.
French
The ear is the road to the heart.
French
Nip the briar in the bud.
French
Nip the briar in the bud.
French
The villain that becomes rich knows neither friends nor family.
French