Preach, rhetors! Sing the praises of persuasion far and wide. Spread the eloquent word like George Campbell, Scottish minister and philosopher. His book, The Philosophy of Rhetoric, situated the art within the age of enlightenment, and helped transition rhetoric from the era of Aristotle into a modern context. Thanks, Pastor Campbell!
Among his sophisticated contributions to rhetoric, Campbell’s four ends of discourse are his most well known. What is the purpose of rhetoric? Campbell answers:
“All the ends of speaking are reducible to four; every speech being intended to enlighten the understanding, to please the imagination, to move the passions or to influence the will.”
In other words, discourse can move us to understand, dream, feel, or act.
Why is this important? Because the purpose of your discourse—what it can do and what you want it to do—should affect its form and flourish. It’s hard to get someone to act, for instance, if you’re using arguments better suited for understanding.
I already discussed some of these ends as they relate to your motivation to persuade, but let’s have a look at what they mean for content and style…