The Rhetoric of Campbell The rhetorical trend we have chosen to call the epistemological school of thought reached its zenith in the writings of George Campbell, a Scottish Presbyterian minister and educator. In the epochal year of 1776, Campbell published his Philosophy of Rhetoric. Among the greatest books on communication theory written in the modern era, Campbell’s work, more than any preceding volume devoted exclusively to rhetoric, brought together the best knowledge available to eighteenth-century scholars. Few men could roam so freely over classical and contemporary thought, and sift from these ideas the most relevant concepts that would contribute significantly to the development of a theory of discourse rooted in human nature and interdisciplinary in its thrust.
As an admirer of the classics, Campbell reminded his theological students to immerse themselves in such specific works as Quintilian’s Institutio Oratoria, Cicero’s De Inventione and De Oratore, the Ad Herennium, Longinus’ On the Sublime, and the critical essays of Dionysius. What he liked most of all was the classical emphasis on rules as an art form. In his Lectures on Pulpit Eloquence, Campbell taunted his contemporaries for their inability to extend the highly artistic approach to rhetoric developed by the ancients. "As to the rhetorical art itself," he said, "in the particular the moderns appear to me to have made hardly any advance or improvement upon the ancients. I can say, at least, of most of the performances in the way of institute, which I have had an opportunity of reading on the subject, either in French or English, every thing valuable is servilely copied from Aristotle, Cicero, and Quintilian."
Underlying Campbell’s philosophy was the idea that rhetoric is a dynamic, developing process. He most earnestly wished, therefore, to incorporate into his inventional theory not only relevant classical precepts but the principal findings of the social and behavioral sciences and select experimental evidence from the natural sciences. In this way, he thought, could be avoided the sterility that results from an undue reliance upon the Greek and Roman rhetoricians.
Book I of the Philosophy of Rhetoric contains Campbell’s most original contributions to rhetorical thought. Included in this section are basic elements of faculty psychology, the laws of association, sympathy, moral reasoning, and what the Scots called "common sense." Campbell began his inquiry by examining the nature of man. The writings of Bacon, Locke, and Hume, reinforced by his own observations and experience, taught him that the mind is separated into faculties. To Locke’s categories of understanding and will, he added imagination and the passions. These were to be viewed not so much as discrete elements but as a hierarchy, ranging from the elementary faculty of the understanding to the more complex faculty of the will. Persuasion, therefore, is the final result of a four step process, that starts with instruction, and proceeds through the imagination and passions until it motivates the will. Campbell explains these relationships in the following way:
In order to evince the truth considered by itself, conclusive arguments alone are requisite. but in order to convince me by these arguments, it is moreover requisite that they be understood, that they be attended to, that they be remembered by me. and in order to persuade me by them to any particular action or conduct, it is further requisite, that by interesting me in the subject, they may, as it were, be felt. It is not therefore the understanding alone that is here concerned. If the orator would prove successful, it is necessary that he engage in his service all these different powers of the mind, the imagination, the memory, and the passions. These are not the supplanters of reason, or even rivals in her sway. they are her handmaids, by whose ministry she is enabled to usher truth into the heart, and procure it there a favourable reception.
From the general considerations Campbell moved to a more detailed discussion of the mental faculties and their relationship to rhetorical practice. Appeals to the understanding, he suggested, consist of explanation and proof. The communicator may have as his purpose to clarify an unknown doctrine or a complex idea. The predominant quality of this end of discourse is perspicuity in language. When the listener, however, approaches a rhetorical situation with an attitude of disbelief or doubt concerning a thesis, the speaker is constrained to use argument in such a way that conviction is achieved.
Campbell felt obliged to begin his discussion of imagination with a brief refutation of those who tended to regard this faculty as beneath the level of serious scholarly inquiry. He then defined imagination as "that faculty of mind, whereby it is capable of conceiving and combining things together, which in that combination have neither been perceived by the senses, nor are remembered." It follows, therefore, that such communication forms as fables, parables, allegories, and poetry are addressed to the imagination. and that part of the discourse most suitable to this appeal is narration. For here the speaker or writer may employ vivid and impelling language, imitation, and resemblances to portray lively and beautiful representations of his subject.
The stimulation of the passions grows naturally out of the descriptions directed to the imagination. Through an association of images, Campbell observed, the emotions are stirred. These lively associations hurry the audience along into feelings of "love, pity, grief, terror, aversion or desire." Campbell added that the emotions experienced by the auditor are especially strong when they are seen operating in the speaker.
The best means of influencing the will, which Campbell called the most difficult task facing a communicator, is to combine in an artful manner strong arguments designed to convince the judgment and graphic emotional appeals related to the passions. In holding that conviction operates on the understanding and persuasion on the will and resolution, Campbell supported the notion that a conviction-persuasion duality exists. Such a dichotomy not only was endorsed by Blair but by rhetoricians for generations to come.
The significance of Campbell’s belief in the faculties may be seen in his definition of eloquence as "that art or talent by which the discourse is adapted to its end." In this system, the listener, rather than the occasion or speaker, becomes the starting point in the construction of a message.
Campbell’s discussion of the forms of proof, long considered the substance of invention, is a comprehensive, yet uneven, analysis revealing his grasp of classical rhetoric, the Bible, and the principal writings of Bacon, Descartes, Locke, and Hume. The fact that Campbell was an orthodox Presbyterian divine, opposing the extremist views of the enthusiasts on the one hand and the scepticism of Hume on the other, is also visible in the development of his inventional theory. This influence is reflected in his treatment of the requirements of a speaker, his positioning of emotional proof, and his partiality for moral reasoning. How Campbell blended these ancient and modern secular and religious forces into a tightly knit, eclectic system of invention is our present concern.