The contribution of the Speculative Grammar to the identification of the adjective as an independent part of speech

The present paper revolves around a series of questions that concern the so-called Speculative Grammar of the Middle ages, such as: why is Speculative Grammar interesting with respect to our contemporary theory of language? What was its role in the evolution of linguistic theories? And, especially, are we aware of its influence on modern linguistic theory? The aim of the present paper is to provide some answers to the questions above by discussing a very specific problem, namely the contribution of the Medieval theory of grammar, and specifically, of Speculative Grammar, to the identification of the adjec-tive as an independent part of speech, distinct from the noun.