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Although the full text of the article is reproduced here, the class reading is an excerpt as indicated in the text.


The Rhetoric of Western of Thought, Campbell, pp 148-157.

The Rhetorics of Campbell and Whately

George Campbell

[148] 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, and in the works of Richard Whately, Archbishop of the Anglican Church. 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.1 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.”2

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 [149] 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.3

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.”4 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.”5 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.6 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.”7 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 [150] into a tightly knit, eclectic system of invention is our present concern.

There are no well-defined sections in any of his works in which Campbell handles the subject of ethical proof. Yet it is possible to go to his Philosophy of Rhetoric, Lectures on Systematic Theology, and occasional sermons to pull out relevant passages that deal with this theme. On April 7, 1752, he delivered a sermon “The Character of a Minister of the Gospel as a Teacher and Pattern.” In this address, Campbell asserted that a preacher trebles his effectiveness whenever his teachings correspond to his practice. Using an argument from less to greater, he pointed out that the minister, whose chief end is persuasion, must adhere to Quintilian’s good man theory.8 Twenty-four years later, in his Philosophy of Rhetoric, Campbell acknowledged the importance of intelligence, yet placed it on a lower plane than character. “Men generally will think themselves in less danger of being seduced by a man of weak understanding, but of distinguished probity,” he said, “than by a man of the best understanding whom is of a profligate life.”9 In making this claim, Campbell in no way meant to denigrate the worth of knowledge on the part of the speaker. He admonished all prospective ministers, for example, to steep themselves in the writings of the classical rhetoricians and orators, and to be conversant with modern authors including Rollin, Fenelon, and Hugh Blair.10

No summary of Campbell’s attitudes toward ethical proof is complete without a reference to the doctrine of sympathy. Cicero, Hume, and Smith taught him to believe that genuine sympathy between the communicator and the listener can only exist when trust is present. It is for this reason that the speaker who demonstrates sincerity and good will has the best chance to create a bond with his audience, and thereby establish the necessary interaction that leads to the influencing of the will.

Campbell was more systematic and original in his treatment of pathetic proof. His conviction that Aristotle was right in assuming the basic rationality of man and in dissecting emotions for the purpose of showing how they may react upon logos was tempered by what he had learned from Locke and Hume about human nature. He accepted Locke’s dichotomy of passions—the “pleasant” and the “painful,” and his contention that passions are held together by an attraction or association. Pity, for instance, is a group of emotions “comprised of commiseration, benevolence, and love.” Campbell further suggested “that pain of every kind generally makes a deeper impression on the imagination than pleasure does, and is retained longer in the memory.”11 Hume’s notions are also present.  Although his belief in the dominance of impressions over ideas did not cause Campbell to modify his hierarchy of ends progressing from the understanding to the will, it did persuade him to see the causal relationship between lively ideas and the imagination and passions.

[The class reading continues after the section on humor]

A peripheral aspect of Campbell’s views on pathetic proof was his penetrating discussion of wit and humor. The mind, he said, is agreeably surprised when a speaker presents novel ideas that debase pompous or seemingly grave things, aggrandizes small and frivolous concepts, or places in juxtaposition dissimilar objects or incongruous events. The process of debasing or aggrandizing a notion derives its strength from appeals to the imagination which may incorporate the method of burlesque. Incongruity, on the other hand, gets its thrust from unlikely associations that generate a surprise meaning. We do not, says Campbell, expect a well-dressed man to fall into a kennel. Thus when a rhetor describes such a happening, we are amused by the incongruity inherent in the situation.

Since wit essentially is a result of novelty and surprise, Campbell came down hard on the use of old jokes as a rhetorical technique. “Nothing is more tasteless, and sometimes disgusting,” be asserted, “than a joke that has become stale by frequent repetition.”12  His belief that the surprise element is a central aspect of wit led him to conclude that “a witty repartee is infinitely more pleasing than a witty attack.” Wit, in short, has as its primary aim to paint and divert. Consequently, it must be, clothed in clever language employing figures of speech and thought that titillate the fancy.

[151] Humor, Campbell goes on to observe, is more pathetic than wit, but since it addresses itself to contempt rather than to imagery and resemblances, it is inferior in nature and function. Notwithstanding this reservation, Campbell proceeds to give several practical hints for employing humor in discourse. Here are a few of his suggestions, all of which pertain to the foibles of human character:

1.      Describe a person’s “caprices, little extravagances, weak anxieties, jealousies, childish fondness, pertness, vanity, and self-conceit.”

2.      Relate familiar stories in a whimsical manner, sometimes assuming a particular character and relying on mimicry and “peculiarities in voice, gesture, and pronunciation.”

3.      Describe your own shortcomings and blunders.

4.      A serious countenance may prove to be beneficial in order to conceal your art.


In his discussion of wit and humor, Campbell observed that these rhetorical strategies designed to produce laughter may have as their goal either to divert,” or to influence the opinions and purposes of the hearers . . . “ The related art of ridicule seeks more to dissuade than to persuade. “It is,” he said, “fitter for refuting error than for supporting truth, for restraining from wrong conduct, than for inciting to the practice of what is right.” Moreover, “it is not properly leveled at the false, but at the absurd in tenets.”

What Campbell said about wit, humor, and ridicule grew out of his theory of human nature. To see how practical these insights have proved to be, we need only look at the writings and speeches of such well-known British figures as Samuel Pepys, James Boswell, George Bernard Shaw, and Winston Churchill.

Throughout his famous Diary, written in the seventeenth century, Pepys engaged in self-disclosure, revealing himself as a humorous man who took great pleasure in describing his “ caprices,” “jealousies” “childish fondness,” and “self-conceit.” With a frankness matched only by Boswell a century later, Pepys lets the reader in on his combative dialogues and other encounters with his wife, his unpredictable and irreverent behavior in church during the preaching of a sermon, and the spying techniques he used to check up on his subordinates. On one occasion following a highly successful speech in the House of Lords, he fancied himself a reborn Cicero. But in order to protect his sudden fame as an eloquent orator, he contemplated an abrupt retirement from the podium so that he could savor his newly-discovered eminence.

If Campbell perhaps had Pepys in mind when he constructed his theories on wit, humor, and ridicule, he also had ample opportunity to learn of the antics of his fellow Scotsman, James Boswell, who had a unique talent for telling stories about himself and others. When he did so, he often employed mimicry and a whimsical manner as suggested by Campbell. Never was this more evident than in his vivid account of the evening when he and Hugh Blair sat “together in the pit of Drury Lane playhouse . . ..” “In a wild freak of youthful extravagance,” said Boswell; “I entertained the audience prodigiously by imitating the lowing of a cow.” He then added with some degree of enjoyment: “I was so successful in this boyish frolic that the universal cry of the galleries was, ‘Encore the cow! Encore the cow!’ In the pride of my heart I attempted imitations of some other animals, but with inferior effect. My reverend friend, anxious for my fame, with an air of utmost gravity and earnestness, addressed me thus: ‘My dear sir, I would confine myself to the cow.”’

The humor in Boswell’s story was enhanced by the presence of incongruity caused by Blair’s participation in the event. The “Minister of St. Giles” was by nature both pompous and discreet. Moreover, since his conservative parishioners in Edinburgh did not permit him to attend a theatrical production, he had to escape to London in order to indulge his aesthetic tastes regarding drama.

Shaw and Churchill, like Pepys and Boswell, were also scintillating storytellers who could arouse the fancy of their audiences. But they also had a remarkable capacity for witty repartee designed to throw an opponent off balance. Their brilliant exchanges presented [152] to each other have formed the basis for numerous dinner table conversations centering on the theme of humor.

[The class reading continues here]

The uniqueness of Campbell’s theory of rhetorical proof may be measured not so much in terms of what he had to say on ethos and pathos as in his remarks on logos. His comments on this phase of invention exemplify the brilliant analytical powers he had sharpened through his reading, writing, and platform presentations. Never was he more prone to depart from the classical teachings and embrace modern psychological and philosophical theory. Notwithstanding the fact that Campbell’s fresh approach led Whately to indict him for apparently failing to understand even the most rudimentary elements of logic,13 he went beyond his contemporaries in synthesizing seventeenth and eighteenth-century scientific thought and applying it to rhetoric.

The heart of Campbell’s theory of logical proof is found in his description of evidence. The first type, which he designates intuitive in nature, bears a close resemblance to the method of knowledge delineated by Bacon and Descartes. It consists of mathematical axioms, derived from intellection, consciousness kept alive by sensory messages, and common sense shared in varying degrees by all mankind. Almost instantly the mind can gain an insight into the meaning and worth of a principle or a reputed fact. But despite the high degree of reliability of this intuitive evidence, Campbell, like Descartes and other rationalists, grew impatient with those who accepted it without a probing analysis. Rarely was this more evident than in a fast day sermon on the duty of allegiance, delivered on December 12, 1776. Observe how he taunted the American colonists for their uncritical acceptance of certain axioms:

Indeed the most consistent patrons of the American cause deny that the legislative power of the British senate can justly extend to the colonies in any thing. . . . This appears to them an axiom in politics as clear as any in mathematics. And though for a first principle, it has been wonderfully late of being discovered, they are so confident of its self-evidence, that they never attempt to prove it; they rather treat with contempt every person who is so weak as to question it. These gentlemen, however, will excuse me, as I am not certain that I understand them, and am a little nice about first principles, when I ask, what is the precise meaning they affix to the term consent? For I am much afraid, that if they had begun with borrowing from the mathematicians, the laudable practice of giving accurate definitions of their terms, and always adhering to those definitions, we had never heard of many of their newfangled axioms . . . 14

In his Philosophy of Rhetoric, Campbell subdivided deductive evidence into scientific proof and moral reasoning. The former is, in effect, a restatement of Cartesian philosophy and, for the most part, resides outside the sphere of rhetoric. It deals with abstract independent truths, relies on a single coherent series, and excludes from its domain any demonstration which contains multiple degrees of certainty or contradictions.15

What, then, is the kind of evidence available to the speaker who seeks to convince or persuade? Moral reasoning is Campbell’s answer. It stands above possibility and probability but below absolute certainty. In the highly important discussion that follows, Campbell draws heavily upon Bacon, Descartes, Locke, and Hume; but because of his religious orientation, he moves in other directions as well. There are four species of moral evidence: experience, analogy, testimony, and calculation of chances. Experience, Campbell points out, is based upon our own observation and provides a useful method of proceeding inductively from a particular example to a universal premise. Further it enables us to isolate the constituent elements of a fact. When an experience is replicated by experimental research, its persuasive appeal is substantially strengthened.

Analogy, in Campbell’s view, is an “indirect experience, founded on some remote similitude.”16 The more distant or ambiguous the relationship between two objects or events, the less rewarding is the comparison. Because of [153] this shortcoming the analogy generally is a weak form of support. To offset this inherent problem, Campbell recommends that numerous analogies be used, but primarily for defensive reasons. Thus while it cannot advance truth, it diminishes the power of an opponent’s refutation.

Campbell’s discussion of the third species of moral reasoning, testimony, constitutes a landmark in argumentation theory. In asserting that it was “an original principle of our nature,”17 Campbell lifted testimony from the inartistic plane described by Aristotle to the level of artistic proof. In 1761, this subject became the theme of his first major work, A Dissertation on Miracles. Designed as a refutation to an earlier study on miracles by Hume, Campbell’s Dissertation set out to prove the weakness of Hume’s claim that “no testimony of a miracle could ever amount to a probability much less a proof.”18 The task, said Campbell, was not an easy one. The difficulty arose from the fact that Hume was more than “subtle” and ”powerful adversary”; he was also an instructor and friend. If he succeeded in answering his opponent, Campbell observed, it would be not merely because truth was on his side but because he had learned to use the very principles and methods taught to him by Hume. With this rationale Campbell stated the proposition that “miracles are capable of proof from testimony.” He then attempted to demonstrate that nothing in human nature, the history of mankind, or common sense has refuted the Biblical account of the miracles. Moreover, he added, testimony has a special affinity with experience because it derives from the observations of others. What makes the Christian miracles believable is that they were corroborated by more than one witness. Such a combination of experiences, when unsuccessfully challenged by contrary evidence, produces moral certainty.”

Ten years later in a sermon delivered before the Synod of Aberdeen on April 9, 1771; Campbell developed similar views on the nature of testimony. After condemning religious enthusiasts for violating the dictates of common sense and the admonitions of their conscience, he drew a parallel between history and the Bible to show that both rely upon testimony for their prime source material.

The history of past ages we derive solely from testimony. Our knowledge of countries which we never saw, and the much greater part of natural history, must proceed to us entirely from the same source. It will be admitted, that on these topics, without such extraneous information, a man of the most enlightened reason, and the most acute discernment, could never investigate aught beyond the sphere of his corporeal senses. If then we receive from a book, pretending to contain a divine revelation, the account of what happened in a period preceding the date of civil history, can it be justly sustained an objection to the veracity of the writer, that he unravels a series of facts, which, by no use or improvement of reason, it would have been in our power to discover? This identical objection would operate equally against all the histories, natural or civil, foreign or domestic, and travels and voyages, that ever were, or ever will be in the world. Nor is this reasoning applicable only to such events as the creation, the fall, and the deluge. Its application to the discoveries revelation brings concerning the designs of Heaven for our recovery, and final happiness, stands precisely on the same footing .20

Campbell thus found in testimony the type of proof he needed to affirm his belief in the authenticity of the Bible. But he was quick to point out that every Biblical account must be subjected to a critical analysis before the evidence could be accepted. “The credibility of the facts related,” he said, “is no proof of their truth, though it be a foundation for inquiry. The next province of reason is, to examine the evidence by which the veracity of the writer is supported . . . ”21 Such a conclusion is similar to Descartes’ Discourse on Method.

These well-honed ideas on testimony, which Campbell had formulated as part of his theology, form the nucleus of his remarks on this subject in the Philosophy of Rhetoric. Again he argued that testimony is experiential in nature because it is based upon the observations [154] of others. Similarly, he maintained that it provided the source material for many disciplines including philosophy, history, grammar, languages, jurisprudence, criticism, and revealed religion. But Campbell added a new dimension when he asserted that testimony is stronger for single facts than is experience. The latter has a higher position only when it leads to a generalized conclusion resulting from experimental studies. Even this advantage can be offset in part, Campbell added, with concurrent testimonies that support a particular observations.22

We reprint Campbell’s full explanation of testimony both because of its historical significance and its present value.

The third tribe is the evidence of testimony, which is either oral or written. This also hath been thought by some, but unjustly, to be solely and originally derived from the same source, experience. The utmost in regard to this, that can be affirmed with truth, is that the evidence of testimony is to be considered as strictly logical, no further than human veracity in general, or the veracity of witnesses of such a character, and in such circumstances in particular, is supported, or perhaps more properly, hath not been refuted, by experience. But that testimony, antecedently to experience, hath a natural influence on belief, is undeniable. In this it resembles memory; for though the defects and misrepresentations of memory are corrected by experience, yet that this faculty hath an innate evidence of its own we know from this, that if we had not previously given an implicit faith in memory, we had never been able to acquire experience. This will appear from the revisal of its nature, as explained above. Nay, it must be owned, that in what regards single facts, testimony is more adequate evidence than any conclusions from experience. The immediate conclusions from experience are general, and run thus: ‘This is the ordinary course of nature. Such an event may reasonably be expected, when all the attendant circumstances are similar.’ When we descend to particulars, the conclusion necessarily becomes weaker, being more indirect. For though all the known circumstances be similar, all the actual circumstances may not be similar; nor is it possible in any case to be assured, that all the actual circumstances are known to us. Accordingly, experience is the foundation of philosophy; which consists in a collection of general truths, systematically digested. On the contrary, the direct conclusion from testimony is particular, and runs thus: ‘This is the fact in the instance specified.’ Testimony, therefore, is the foundation of history, which is occupied about individuals. Hence we derive our acquaintance with past ages, as from experience we derive all that we can discover of the future. But the former is dignified with the name of knowledge, whereas the latter is regarded as matter of conjecture only. When experience is applied to the discovery of the truth in a particular incident, we call the evidence presumptive; ample testimony is accounted a positive proof of the fact. Nay the strongest conviction built merely on the former is sometimes overturned by the slightest attack of the latter. Testimony is capable of giving us absolute certainty (Mr. Hume himself being judge) even of the most miraculous fact, or of what is contrary to uniform experience. For, perhaps, in no other instance can experience be applied to individual events with so much certainty, as in what relates to the revolutions of the heavenly bodies? Yet, even this evidence, he admits, may only be counterbalanced, but destroyed by testimony.

But to return. Testimony is a serious intimation from another, of any fact or observation, as being what he remembers to have seen or heard or experienced. To this, when we have no positive reasons of mistrust or doubt, we are, by an original principle of our nature (analogous to that which compels our faith in memory), led to give an unlimited assent. As on memory alone is founded the merely personal experience of the individual, so on testimony in concurrence with memory is founded the much more extensive experience which is not originally our own, but derived from others. By the first, I [155] question not, a man might acquire all the knowledge necessary for mere animal support, in that rudest state of human nature (if ever such a state existed) which was without speech and without society; to the last, in conjunction with the other, we are indebted for every thing which distinguishes the man from the brute, for language, arts, and civilization. It hath been observed, that from experience we learn to confine our belief in human testimony within the proper bounds. Hence we are taught to consider many attendant circumstances, which serve either to corroborate or to invalidate its evidence. The reputation of the attester, his manner of address, the nature of the fact attested, the occasion of giving the testimony, the possible or probable design in giving it, the disposition of the hearers to whom it was given, and several other circumstances, have all considerable influence in fixing the degree of credibility. But of these I shall have occasion to take notice afterwards. It deserves likewise to be attended to on this subject, that in a number of concurrent testimonies (in cases where there could have been no previous concert), there is a probability distinct from that which may be termed the sum of the probabilities resulting from the testimonies of the witnesses, a probability which would remain even though the witnesses were of such a character as to merit no faith at all. This probability arises purely from the concurrence itself. That such a concurrence should spring from chance is as one to infinite; that is, in other words, morally impossible. If therefore concert be excluded, there remains no other cause but the reality of the fact.

Now to this species of evidence, testimony, we are first immediately indebted for all the branches of philology, such as, history, civil, ecclesiastic, and literary; grammar, languages, jurisprudence, and criticism; to which I may add revealed religion, as far as it is to be considered as a subject of historical and critical inquiry, and so discoverable by natural means: and secondly, to the same source we owe, as we hinted above, a great part of that light which is commonly known under the name of experience, but which is, in fact, not founded on our own personal observations, or the notices originally given by our own senses, but on the attested experiences and observations of others. So that as hence we derive entirely our knowledge of the actions and productions of men, especially in other regions and in former ages, hence also we derive, in a much greater measure than is commonly imagined, our acquaintance with Nature and her works--Logic, rhetoric, ethics, economics, and politics are properly branches of pneumatology, though very closely connected with the philological studies above enumerated.23

The inclusion of calculation of chances as the fourth species of moral reasoning gave Campbell pause because of its mixed nature. Sharing some of the characteristics of both demonstrative and moral evidence, it is difficult to categorize with precision. What Campbell hoped to do was to devise some type of method that would assist the communicator in establishing a strong probability when the elements of experience, analogy, and testimony were contradictory and incapable of further experimental validation. With the aid of mathematics, one might predict on the basis of past experiences stored in his memory what the likely statistical probability of an occurrence may be. In this sense it is demonstrative. But one might also use reason for the purpose of balancing all of the possibilities inherent in both sides of a question. The calculation of chances is then made on the grounds of degree of moral certainty. This kind of proof which relates mathematics and logic to experience and chance can be illustrated, concluded Campbell, “in the computations that have been made of the value of annuities, insurances, and several other commercial articles.”24

A final elaboration of Campbell’s theory of moral evidence appears in his discussion of the syllogism. Following in the tradition of Descartes, Locke, and Hume, he rebelled against what he called the scholastic art of syllogizing. In his attack he presented four indictments. First, the syllogism, in proceeding by synthesis [156] and from universals to particulars, runs counter to moral reasoning which proceeds by analysis and from particulars to universals. Secondly, it has not been used by mathematicians as an appropriate means of demonstrating theorems. Thirdly, it is of little utility in applying knowledge stemming from experience. Lastly, since it is confined primarily to the adjustment of language to express previously known concepts, it contributes nothing, to our understanding.25

Campbell’s inventional theory, in sum, partook more of the modern scientific thought than of classical precepts. The investigatory nature of the Greek and Roman inventional system, with its stress on topics and commonplaces as a means of generating new arguments and evidence, was largely discounted. Since every man is endowed with a memory, he may begin construction of a discourse, not by following the road of inquiry in search of new materials, but by recalling the information that had come to him earlier by way of intellection and experience, and by familiarizing himself with the findings already engendered by logic. “As logic therefore forges the arms which eloquence teacheth us to wield,” Campbell observed, “we must first have recourse to the former, that being made acquainted with the materials of which her weapons and armour are severally made, we may know their respective strength and temper, and when and how each is to be used.”26 This decision to accept the Baconian distinction between inquiry and transmission gave to invention a managerial rather than an investigatory function.

If Campbell’s provocative notions on inventional theory stand as his greatest single contribution to rhetorical thought, his notions on audience analysis and adaptation and on language control and style perhaps have had the longest range influence on rhetorical practice and pedagogy. With considerable foresight he told prospective speakers what they need to know about audiences in general and audiences in particular. We can assume as a starting point in speech preparation, he argued, that all men and women are endowed with an understanding, an imagination, a memory, and passions. It behooves persuasive speakers, therefore, to use arguments that can be understood, to employ language that is vivacious and lively, to provide an organizational pattern and form of repetition that stimulate the memory, and to utilize appeals that arouse the emotions. Concluding that “passion is the mover to action” and “reasoning the guide,” Campbell listed the following seven “circumstances that are chiefly instrumental in operating on the passions”:

  1. Probability
  2. Plausibility
  3. Importance
  4. Proximity of Time
  5. Connection of Place
  6. Relation to the Persons addressed
  7. Interest in the Consequences


From these general considerations, he moved to an analysis of the things which a speaker should know about his particular audience. These include such matters as educational level, moral culture, habits, occupation, political leanings, religious affiliation, and locale. The excerpt which follows, while revealing some of Campbell’s biases, nevertheless is a useful reminder regarding the speaker’s need to know the characteristics of a particular audience. “Now, the difference between one audience and another is very great, not only in intellectual but in moral attainments. That may be clearly intelligible to a House of Commons, which would appear as if spoken in an unknown tongue to a conventicle of enthusiasts. That may kindle fury in the latter, which would create no emotion in the former but laughter and contempt. . . . Liberty and independence will ever be prevalent motives with republicans, pomp and splendour with those attached to monarchy. In mercantile states, such as Carthage among the ancients, or Holland among the moderns, interest will always prove the most cogent argument; in states solely or chiefly composed of soldiers, such as Sparta and ancient Rome, no inducement will be found a counterpoise to glory. Similar differences are also to be made in addressing different classes of men. With men of genius the most successful topic will be fame; with men [157] of industry, riches; with men of fortune, pleasure.”27

Campbell’s discussion of language and style was similar to that expressed by Blair and other belletristic scholars. He supported the element of perspicuity because of its importance in developing appeals to the faculty of understanding. Similarly, figurative language performs an essential role in stimulating the imagination and the passions. The use of language, therefore, has a strong correlation with invention. While it is not our purpose here to present a thorough review of Campbell’s theory of style, we feel it is appropriate to highlight his doctrine of usage. We do so because of the tremendous impact which this theory has exerted on subsequent rhetorical literature. As can be seen from an examination of the following passages, Campbell upholds the notion that language should conform to the criteria of “reputable” “national,” and “present” use.28 Later we will observe how the contemporary rhetorician I. A. Richards rejects this approach.