to the three forms of the genre: the guidebook, the gastronomic treatise, and the gourmet periodical. The invention of gastronomic literature coincided with important cultural transformations in France that increased the relevance of the subject. The end of nobility in France changed how people consumed food; fewer wealthy households employed cooks and the new bourgeoisie class wanted to assert their status by consuming elitist food. The emergence of the restaurant satisfied these social needs and provided good food available for popular consumption. The center of culinary excellence in France shifted from Versailles to Paris, a city with a competitive and innovative culinary culture. The culinary commentary of Grimod and other gastronomes influenced the tastes and expectations of consumers in an unprecedented manner as a third party to the consumer-chef interaction. The French origins of gastronomy explain the widespread use of French terminology in gastronomic literature. Pascal Ory criticizes this literature as conceptually vague; relying heavily on anecdotal evidence; and using confusing, poorly defined terminology. Nevertheless, gastronomy has grown from a marginalized subject in France to a serious and popular interest worldwide. The derivative gourmet has come into use since the publication of Physiology of Taste () an 1825 cooking treatise by Jean Anthelme Brillat-Savarin, a lawyer and politician who aimed to define classic French cuisine. While the work contains some flamboyant recipes, it goes into the theory of preparation of French dishes and hospitality. According to Brillat-Savarin: "Gastronomy is the knowledge and understanding of all that relates to man as he eats. Its purpose is to ensure the conservation of men, using the best food possible." Writings on gastronomy Many writings on gastronomy throughout the world capture the thoughts and aesthetics of a culture's cuisine during a period in their history. Some works continue to define or influence the contemporary gastronomic thought and cuisine of their respective cultures. Some additional historical examples: or (On the Subject of Cooking): A 1st-to-5th-century collection of ancient Roman recipes, often attributed (without clear evidence) to the gourmet Marcus Gavius Apicius, it contains instructions for preparing dishes enjoyed by the elite of the time. A new English translation was published in 2009 as Cookery and Dining in Imperial Rome. (, The Way of Eating, also known in English as Recipes from the Garden of Contentment): An 18th-century manual on Chinese cuisine of Qing dynasty by the poet Yuan Mei, it contains recipes from different social