In the old days, a middle-aged Man had one wife that was old and one that was young; each loved him and desired to see him like herself. One wife was much younger than the man, and the other wife was much older.
Since the wives quarrelled a lot, the man built two houses for each of them in different parts of town. They came to a mutual agreement that the man would stay with each of them on alternate days.
The older wife was embarrassed at being married to a man much younger than herself. At night, whenever he was with her, she would pluck out all of his hairs that were not grey. The younger woman was equally embarrassed at being married to a man so much older than herself. At night, whenever he was with her, she would pluck out all of the hairs that were grey.