 There are nineteen chapter divisions to part one. Chapters 1–3 lay the groundwork by discussing the basic purposes of human language. Here, Dante quite rightly recognizes that, even were we to regard intellectual content as immaterial, human beings are nevertheless constituted in such a way as to derive intellectual content initially from sensation directly (as in the case of induction arriving at a first principle) or through the sensory communication of intellectual content from one human being to another (as in the case of dialectical or rhetorical engagement). Languages thus convey thinking but do so in a material medium (e.g., sound produced by one person’s vocal cords and vibrating another person’s receiving organ of the ear). Indeed, for Dante, this use of language is at the very core of what it means to be human since, unlike other animals and also unlike angels and demons, “in order to communicate their mental conceptions (conceptiones) to one another, men had to have some kind of rational and sensory sign…rational because it would both arise from and lead to reason…[and sensory] since nothing can be transferred from one reasoning mind to another except by sensory means.” [1.3.2].