Two Books of the Elements of Rhetoric

What its parts or species are.
What its causes.
What its effects.
What things are related and what things are contrary.

These topics should be consulted when we wish to teach men about some matter. And minds must be accustomed so that, whatever matter has been proposed, they immediately look into these topics, which advise where the material should be sought, or at least what ought to be chosen from a large heap and in what order it should be distributed. For the topics of invention, both among Dialecticians and among Rhetoricians, contribute not so much to finding the material as to choosing it, after some heap of things has been offered either from another art or from the business itself.

In every matter, the definition ought to come first. The topic "what it is" orders one to seek this. But sometimes one disputes about the naming first, and the meaning of the word must be established, for it is well known that there are countless logomachias verbal contentions and bickerings about words. Therefore, at the beginning, lest the ambiguity of speech beget error, a certain meaning of the word must be established.

And especially in Theological disputes, the phraseology of the sacred letters must be observed, because we use many Hebrew figures, which, if they are not correctly rendered, many errors follow; for instance, Pelagius understood Grace as only the benefit of the revealed law and doctrine.