Do you typically require a guest list before you agree to attend a dinner party?
You do require a guest list if you have numerous blood feuds on the go. The guest has a right to ask who else is coming. You would think inviting people from different centuries would avoid problems, but apparently not according to Eugenides:
“Tolstoy,” I answer. “I’m busy that night,” Shakespeare says.First I call Shakespeare. “Who else is coming?” Shakespeare asks.
These days, you email the list to everyone. You do not blindcopy. That gives all the attendees a chance to research all the other guests, so that at an opportune moment, one might say, "I see you own a walnut farm in Uttarakhand, India. I hear business is exploding." (At least that's what I do whenever possible.)