[5][12] The work describes figurative language, rhetorical devices, and irregular Latin grammar[13] using "sophisms" or illustrative examples.
[14] It aims to complement Bacon's students' required readings of Priscian's work On Construction by presenting its important points in a more thorough and logical order.
[15] The first section lays out rules regarding grammatical agreement and the rhetorical devices antithesis,[16][17] synthesis,[18][19] procatalepsis,[20][21][8] From the Aristotelian notion that "art imitates nature to the extent that it can"[22][23] and under the influence of Averroës's commentaries,[8] Bacon argues that nouns and pronouns can be distinguished from verbs and adverbs owing to the distinction between permanent and successive things.
[34] The primary ones are Moris erat Persis ducibus tunc temporis omnem ducere in arma domum,[35] Vestes quas geritis sordida lana fuit,[36] Amatus sum vel fui,[37] Vado Romam que est pulcra civitas,[38] Video centum homines uno minus,[39] Lupus est in fabula,[40] In nostro magistro habet bonum hominem,[41] Margarita est pulcherrimus lapidum,[42] Quid nisi secrete leserunt Philide silve,[43] and Nominativo hic magister.
[34] The fourth section analyses short sentences, along with adverbial phrases and liturgical formulas[8] such as ite missa est[45] whose use of ellipsis presented certain problems.
[50][51] Bacon emphasizes that grammatical rules cannot be applied mechanistically but must be understood as a structure through which to attempt to understand the author's intent (intentio proferentis).