It has to be noticed that in Bacon's, as well as in any other medieval sign-typology, the classes of signs — even though this is not explicitly stated by the authors themselves — distinguish modes of signifying rather than signs in the sense of sign-vehicles. Therefore, one and the same thing, fact, or event may, in different respects, fall under various and even opposite sign-classes. This fact is especially important for the full account of sign-processes in which spoken language is involved.