If two friends ask you to judge a dispute, don't accept, because you will lose one friend; on the other hand, if two strangers come with the same request, accept because you will gain one friend.
Source: In The Ultimate Success Quotations Library, 1997.
-- Saint Augustine, (Nov 13 354-430), Roman religious figure, philosopher; He was considered the founder of Christian theology who wrote City of God, 413-426.