The Stoics had made a clear distinction between proper names and common nouns, listing them as different parts of speech, but while this possibility was recognized by Priscian and the influential twelfth century grammarian, Peter Helias, it was not adopted. According to Priscian, the nomen, the noun or name, is the first of the principal parts of speech, and it signifies substance with quality, that is, it signifies a thing of a certain sort, or an individual established in a certain nature. The