The art of persuasion, Rhetoric is the common and popular alternative to Logic. That's not to say there's not some overlap between the two. Mostly, it's just that Rhetoric tends to embellish a bit compared to his goody-two-shoes brother, mixing in ethics and emotional appeal to any given argument. We're sure he'll get into college, anyway, though, and he's quite popular with Charismatic sorts of people, so in the long run Rhetoric is probably still as good a choice.
So, to clarify, Rhetoric is commonly used in Challenges to absolve non-violent verbal arguments, by means of bluffing and other means of persuasion.
Vituperation: The most basic of Rhetorical attacks - sometimes simply called "Flaming" in some circles. Encompasses your enemy in scorching fumes of pure vitriol for DEXTERITY rounds, dealing one Hit Level of fire damage each time the affected enemy has his turn.
Dangling Participle: Outside of combat, you may leave a subtle tear in the grammatical structure of the universe at any single location you desire at a time. The next living thing that approaches its vicinity will find itself suddenly caught between two interpretations of the universe, causing it to become confused for DEXTERITY turns.
Elocution: Fire off an electrifying speech, shocking an enemy into stunned silence! The target enemy is stunned for DEXTERITY turns, during which he deals DEXTERITY less damage when attacking.
Chreia: By relating a brief, chilling anecdote (okay so this is stretching things a bit) you may reduce an enemies' ability to Defend this turn by your DEXTERITY.
Elements of Style: At the cost of fizzling one of his captured Elements, the philosopher may unleash a dazzling display of rhetoric, utilizing Vituperation, Elocution and Chreia in a single turn!