Rules I learned from my mother:
1. Always invite the stranger in--there's always enough room at the table for a few more teenagers, MIT graduate students, Sudanese refugees, difficult (or easygoing) relatives, lonely co-workers, or elderly neighbors. Always.
2. No fake food! Insist on real butter, good coffee, fresh bread.
3. Leftover blackberry pie is a perfectly good breakfast food.
4. Stand up straight; you'll look better and feel better too.
5. If you're not hungry enough to eat an apple or some carrot sticks, you're probably not hungry.
6. Hang up your clothes! (I'm still working on this one)
7. To breastfeeding mothers: Quit worrying about everything. Sit down, put your feet up, and have a beer. It's good for you and good for the baby.
8. Celebrate life's milestones, big and small. Not just birthdays and anniversaries, but Fridays, report card days (even if the report cards aren't perfect), rainy days, etc.
9. A brisk walk cures (almost) all.
10. Even a simple meal, when served and eaten with love, can be a feast.