Leave the table while you still feel you could eat a little more.
Source: In Words of Wisdom, by Wm. Safire & Leonard Safire, 1989.
-- Helena Rubinstein, (Dec 25 1870-1965), US cosmetician, executive, philanthropist; She was the founder and president of Helena Rubinstein, Inc., 1902, a leading manufacturer and distributor of women's cosmetics.