Grammar, logic, and rhetoric each answer a different question about the same arrangement of words. Grammar asks whether something is correctly said. Logic asks whether what is said is true and whether its conclusions follow from its premises. Rhetoric asks whether an audience has been persuaded of the relevant truth. Together they are the foundations of how we express ourselves, how we show that something is true, and how we persuade others of that truth.
| Object | Act | Result | |
|---|---|---|---|
| Grammar | Significant speech and its arrangement | Arranging words so that something is said | A correctly formed sentence |
| Logic | The three acts of the mind: term, proposition, argument | Ordering discourse toward truth | A definition, a true proposition, a valid conclusion |
| Rhetoric | This case and this audience | Finding the available means of persuasion | Assent to what is true and good |
Learning the arts
Each art is learned in two ways: as a set of doctrines on which the art is based and as the art itself to be practiced as a skill. Often students move from one art to the other and later return to the earlier art with better questions and better insights about the whole of discourse and how its parts relate to each other. That is the ideal.
- Grammar: Grammar, then Ars Grammatica, beginning with What Grammar Is.
- Logic: Logic, then Ars Logica, beginning with What Is Logic · An Orientation.
- Rhetoric: Rhetoric, then Ars Rhetorica, beginning with Act I, What Rhetoric Is.
The order of the arts
The classical order is grammar, then logic, then rhetoric, because a statement is made of words and because an audience should be persuaded only of what has been shown to be true. It is not the only defensible order. Houser, in his own modern textbook, Logic as a Liberal Art, puts rhetoric before logic, because students now encounter so much in print and visual media and online that is designed to persuade them subtly and in many ways that they need to recognize ethos, pathos, and logos early. That is a reasonable choice, provided we then go on to logic. This course keeps the classical order, because rhetoric ordered to the truth needs a truth to be ordered toward, and logic is the art that establishes it.
Continue to The Quadrivium.