In 1746, Robert Morris, an 18th-century architectural innovator, authored A Reasonable Plea for the Animal Creation. It never entered the vegetarian canon, nor is it listed among his other published works. The bulk of the book is devoted to reprinting nine letters Morris had sent to a friend defending his abstinence from eating meat. He also responds to published arguments that the book of Genesis prohibits eating of blood but permits the eating of animals. I provide an introduction to the book and excerpts from the letters. Morris’s arguments include that in an interconnected world, flesh eating exhibits rank Pride and Haughtiness of Soul, that the Golden Rule guides humans not to prey on animals, that animal confinement causes illness and infections, and that we have no right of property from nature. Morris’s work is a valuable addition to vegetarian history, to discussions of veganism, and to factory farming and animal confinement debates.