Have her there by all means.
Go ahead with your dinner as though naught sensational and
revolutionary were about to happen. Give them in proper turn the
oysters, the fish, the entree, the bird, the salad. And then, all
by itself, alone and unafraid, bring on a dab of string-beans.
Wait until you see the whites of their eyes, and aim and fire at
will. Settle back then, until the first hushed shock has somewhat
abated - until your dazed and suffering rival is glaring about in
a well-bred but flustered manner, looking for something to go with
the beans. Hold her eye while you smile a smile that is compounded
of equal parts - superior wisdom, and gentle contempt for her
ignorance - and then slowly, deliberately, dip a fork into the beans
on your plate and go to it.
Believe me, it cannot lose. Before breakfast time the next morning
every woman who was at that dinner will either be sending out
invitations for a dinner of her own and ordering beans, or she
will be calling up her nearest and best friend on the telephone
to spread the tidings.