This is 2022 - you can get old cookbooks from archive.org and check if Nathan was right.
He wasn't.
For example, "The up-to-date sandwich book : 400 ways to make a sandwich", by Eva Greene Fuller. Published in Chicago in 1909. https://archive.org/details/uptodatesandwich00full/page/n7/m...
Or, a generation earlier in 1884, the book "Salads and Sauces" by Thomas Jefferson Murrey (New York) has a chapter on sandwiches. https://archive.org/details/saladsandsauces00murrgoog/page/n... including "Apple Sandwich", "Anchovy Sandwich", "Beef, Raw, Sandwich", "Brie Sandwich", "Caviare Sandwich", "Clam Sandwich", "Curry Sandwich", "Dandelion Sandwich", "Duck Sandwich", and so on for several more pages, ending with "Welsh Sandwich". Look under "Goose Liver" for the foie gras entry.
I hope I helped save your meal!