Both edible and medicinal plants were classified by their qualities in the Middle Ages. A given plant might be heating, cooling, moistening, or drying in its action on human bodies; the intensity of this action was expressed in degrees. An herb or foodstuff that was a little cooling was “cold in the first degree,” while a very cooling plant was classed as “cold in the fourth degree.” Above, left: Strawberry (Fragaria vesca) was a mildly cooling fruit, being cold and moist in the first degree. Pear (Pyrus communis) was more refreshing, being cold in the second degree and moist in the first.
The medicinal model inherited by the Middle Ages, based largely on humoral theory, was essentially a “cure by contraries” rooted in the idea that illness was the result of an imbalance of the humors—blood, choler, bile, and phlegm—within an individual. Plants and other substances were either warming, cooling, moistening, or drying in their action on human bodies, which were sanguine, phlegmatic, melancholic, or choleric in complexion. Read more »