"ONE BENEFIT of growing up is learning one's own limits, such as how to stop drinking before trouble begins, or how to avoid parties you won't enjoy. "

I now know that I won't enjoy a three-hour visit to a 40-person party if I don't know most of the guests. My sister has a higher tolerance for huge bashes, while my boyfriend can barely stand anything but an intimate dinner setting. We've learned how to make cameos (thanks for teaching me, sis) and how to gauge ourselves and politely leave when we're bored or tired.

If you learned these skills before finishing high school, please forgive me for marveling. I wasn't very good at parties back then, but most of those parties I attended involuntarily.

My parents took the whole family to Indian shindigs. They all blur together in my memory; surely we didn't go every weekend? We drove over the Altamont Pass from Stockton to the boomtown houses and apartments of fellow immigrants.

Sometimes my dad (a Hindu priest) performed a housewarming, a wedding, or some other religious ceremony. Or we just gathered for food and fellowship.

I couldn't remember the innumerable aunties' and uncles' names and felt embarrassed and overwhelmed. So I'd hide in bedrooms and read, or take naps.

I used to sit reading in the living rooms, ignoring conversation, until my father explained to me that I was insulting the other guests by implying that they were boring me: "Bringing a book to a social gathering is like bringing a sandwich to a dinner party."

Of course, you have to bring a sandwich to a dinner party if you'd go hungry otherwise. This happened at my house last month. A friend informed us at the last minute that a wheat-allergic carnivore was coming, and there wasn't time for us to prepare the appropriate food. The menu as devised did please the majority of the guests, who were mostly vegetarians, but of course the hostess (me) felt flustered.

Please, people with dietary restrictions: Tell your party host about them several days before the event. Don't depend on the person who's bringing you. If you have allergies, or religious taboos, or strong visceral dislikes, tell us. Otherwise you'll feel hungry, and we'll feel guilty.

My more left-brained friends don't see why I felt guilty. In their eyes, the lack of proper warning gives the host a free pass, and any suffering is the guest's own fault.

I refute their ethical argument with a pragmatic one. A guest who doesn't enjoy the party drags down the zeitgeist of the thing. It's all well and good to say "to each his own," but parties are social animals. The negative vibes and body language of one attendee makes the hostess' job harder. And although it's not fair, a single party pooper can ruin the hostess' (and guests') party experience.

I imagine new mothers with colicky babies feel as flustered as I did during one party, where a guest seemed to dislike attending but frustrated all my attempts to help. Do you want food? Drink? Do you need to go to the bathroom? Do you need to be away from the crowd, or seated near your friends? Should I cuddle and burp you?

I find myself with two contradictory ethics of hostessing. One, a very rational model, tells me that guests must responsibly learn to express their own needs, as I've learned to. But my parents' older principles tell me there's no excuse for an uninformed, unprepared or uninspired hostess.

We take upon ourselves a holy duty of generous hospitality and treat the guest as an incarnation of God.

The late Jon Postel, an architect of the Internet, suggested a standard of good Net citizenship that helps me reconcile even this engineering-unrelated dilemma:

"Be liberal in what you accept and conservative in what you send."

I'll do my best and cut others slack and trust that they'll do the same for me.

Sumana Harihareswara writes for Bay Area Living weekly. You can write to Sumana at sumana@crummy.com.