structural:reformatting, structural:expansion
History

Ancient Greek philosopher Theophrastus divided the plant world into trees, shrubs, and herbs. Herbs came to be considered in three groups, namely pot herbs (e.g. onions), sweet herbs (e.g. thyme), and salad herbs (e.g. wild celery). During the seventeenth century as selective breeding changed the plants size and flavor away from the wild plant, pot herbs began to be referred to as vegetables as they were no longer considered only suitable for the pot.

Botany and the study of herbs was, in its infancy, primarily a study of the pharmacological uses of plants. During the Middle Ages, when humoral theory guided medicine, it was posited that foodstuffs, possessing their own humoral qualities, could alter the humoral temperaments of people. Parsley and sage were often used together in medieval cookery, for example in chicken broth, which had developed a reputation as a therapeutic food by the 14th century. One of the most common sauces of the age, green sauce, was made with parsley and often sage as well. In a 14th-century recipe recorded in Latin "for lords, for settling their temperament and whetting their appetite" green sauce is served with a dish of cheese and whole egg yolks boiled in watered down wine with herbs and spices.