There's some nice lists here. If we were really sharing a meal, I'd want the food to be the focus, and the conversation to germinate organically from our taste buds. So in that case, I think of:

Alice Waters
José Andrés
Anthony Bourdain (miss seeing him)
Charlie Trotter (really miss him)

But if conversation were the focus, maybe over a 25 year old Glenlivet and a good Cuban, I'd want:

David Hume
Thomas Paine
Robert Green Ingersoll
Mark Twain

Maya Angelou
Willa Cather
Walter Cronkite
Eleanor Roosevelt

There's so many to choose from, but.....

George Carlin
Thomas Paine
Gandhi
Any of my ancestors

My Dad
Florence Nightingale
Marie Curie
Justice Bertha Wilson

Picking four, because you did...

Marie Marvingt
Alfonsina Strada
Mary Wollstonecraft
Rosa Luxemburg