When two people quarrel both are just, both think they are on the right. And a third person has no right to interfere. Therefore brotherhood cannot be brought about to satisfactory results only by teaching the law of reciprocity based upon self-interest. Because even if they said: "I will give you a pound in gold and you will give me in return a pound" and the exchange is made there is a dispute. Because, "I gave you the pound in gold and you gave me the pound in notes." A friendship which is based upon selfishness is not secure, it is not dependable. Because seemingly they may be friends, in reality each is wanting for himself. They are not the friend of the other, they are the friends of themselves.