To understand the substantive character of natural philosophy, it is essential to describe the kinds of literature in which medieval natural philosophers expressed their thoughts. In Chapter 7, I mentioned the two most basic forms of scholastic literature: (1) the commentary on a text and (2) the questions format in which the author, or commentator, formulates a series of questions on Aristotle's text, posing the questions sequentially in the order of the text. Examples from both of these types will illustrate the most fundamental methods of conveying natural philosophy to a broad audience.

Textual Commentaries on the Works of Aristotle

In the preceding chapter, I distinguished four varieties of textual commentaries. Because the first two methods were used primarily for teaching and conveyed little of the commentator's opinions, I shall illustrate only the third and fourth types. The third type was that in which the commentator separated his commentary from the text on which he was commenting. This could take two forms, the first of which involved a section-by-section sequential commentary on the text, while the second was a paraphrase of Aristotle's text.

The section-by-section sequential commentary was probably the most popular and probably the easiest to follow. In this method, the commentator cited a section of Aristotle's text followed by his commentary on that passage, a technique that derived from Averroes, the great twelfth-century Islamic commentator, who quoted a section of Aristotle's text followed by comments, in which he explained Aristotle's meaning and intent.