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without a cause, than that the existence of the thing could not be so determined. Another insists very curiously, that if a thing had no cause, it must have been the cause of itself; a third, with equal consistency, that nothing must have been the cause. Thus, by always assuming the absolute necessity of a cause, they demonstrate the absolute necessity of a cause. For a full illustration of the futility of such pretended reasonings, see the Treatise of Human Nature, B. I. Part ii. Sect. 3. I do not think they have succeeded better who have attempted to assign a reason for the faith we have in this principle, that the future will resemble the past. A late author imagines, that he solves the difficulty at once, by saying, that “what is now time past, was once future; and that though no man has had experience of what is future, every man has had experience of what was future.” Would it then be more perspicuous to state the question thus, “How come we to believe that what is future, not what was future, will resemble the past ?” Of the first he says expressly, that no man has had experience, though almost in the same breath he tells us, not very consistently, “ The answer is sufficient, have we not always found it to be so ?" an answer which appears to me not more illogical than ungrammatical. But admitting with him, that to consider time as past or future (though no distinction can be more precise,) is only puzzling the question ; let us inquire whether a reason can be assigned, for judging that the unknown time will resemble the known. Suppose our whole time divided into equal portions. Call these portions A, B, C, D, E, F, G. Of these the three first have been experienced, the remaining four are not. The three first I found to resemble one another, but how must I argue with regard to the rest ? Shall I say, B was like A, therefore D will be like C; or, if you think it strengthens the argument, shall I say, C resembled A and B, therefore D will resemble A, B, and C? I would gladly know what sort of reasoning, scientifical or moral, this could be denominated; or what is the medium by which the conclusion is made out ? Suppose, farther, I get acquainted with D, formerly unknown, and find that it actually resembles A, B, and C, how can this furnish me with any knowledge of E, F, and G, things totally distinct? The resemblance I have discovered in D to A, B, and C, can never be extended to any thing that is not D, nor any part of D, namely to E, F, and G; unless you assume this as the medium, that the unknown will resemble the known; or which is equivalent, that the future will resemble the past. So far is this principle, therefore, from being deduced from particular experiences, that it is fundamental to all particular deductions from experience, in which we could not advance a single step without it. We are often misled in cases of this nature, by a vague and popular use of words, not attending to the nicer differences in their import in different situations. If one were to ask me, “Have you then no reason to believe that the future will resemble the past ?” I should certainly answer, “I have the greatest reason to believe it.” And if the question had been concerning a geometrical axiom, I should have returned the same answer. By reason we often mean, not an argument, or medium of proving, but a ground in human nature on which a particular judgment is founded. Nay farther, as no progress in reasoning can be made where there is no foundation, (and first principles are here the sole foundation,) I should readily admit, that the man who does not believe such propositions, if it were possible to find such a man, is perfectly irrational, and consequently not to be argued with.
OF THE CONSIDERATION WHICH THE SPEAKER OUGHT TO HAVE OF
THE HEARERS, AS MEN IN GENERAL.
Rhetoric, as was observed already, not only considers the subject, but also the hearers and the speaker. * The hearers must be considered in a twofold view, as men in general, and as such men in particular.
As men in general, it must be allowed there are certain principles in our nature, which, when properly addressed and managed, give no inconsiderable aid to reason in promoting belief. Nor is it just to conclude from this concession, as some have hastily done, that oratory may be defined, “ The art of deception.” The use of such helps will be found, on a stricter examination, to be in most cases quite legitimate, and even necessary, if we would give reason herself that influence which is certainly her due. 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 farther 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. As handmaids they are liable to be seduced by sophistry in the garb of reason, and sometimes are made ignorantly to lend their aid in the introduction of falsehood. But their service is not on this account to be dispensed with ; there is even a necessity of employing it founded in our nature. Our eyes and hands and feet will give us the same assistance in doing mischief as in doing good ; but it would not therefore be better for the world, that all mankind were blind and lame. Arms are not to be laid aside by honest men, because carried by assassins and ruffians; they are to be used the rather for this very reason. Nor are those mental powers of which eloquence so much avails herself, like the art of war or other human arts, perfectly indifferent to good and evil, and only beneficial as they are rightly employed. On the contrary, they are by nature, as will perhaps appear afterwards, more friendly to truth
than to falsehood, and more easily retained in the cause of virtue than in that of vice. *
MEN CONSIDERED AS ENDOWED WITH UNDERSTANDING,
But to descend to particulars ; the first thing to be studied by the speaker is, that his arguments may be understood. If they be unintelligible, the cause must be either in the sense or in the expression. It lies in the sense, if the mediums of proof be such as the hearers are unacquainted with ; that is, if the ideas introduced be either without the sphere of their knowledge, or too abstract for their apprehension and habits of thinking. It lies in the sense likewise, if the train of reasoning (though no unusual ideas should be introduced,) be longer, or more complex, or more intricate, than they are accustomed to. But as the fitness of the arguments in these respects depends on the capacity, education, and attainments of the hearers, which in different orders of men are different, this properly belongs to the consideration which the speaker ought to have of his audience, not as rnen in general, but as such men in particular. The obscurity which ariseth from the expression will come in course to be considered in the sequel.
MEN CONSIDERED AS ENDOWED WITH IMAGINATION.
The second thing requisite is that his reasoning be attended to; for this purpose the imagination must be engaged. Attention is pre
requisite to every effect of speaking, and without some gratification in hearing, there will be no attention, at least, of any continuance. Those qualities in ideas which principally gratify the fancy are vivacity, beauty, sublimity, novelty. Nothing contributes more to vivacity than striking resemblances in the imagery, which convey, besides, an additional pleasure of their own.
But there is still a farther end to be served by pleasing the imagination, than that of awakening and preserving the attention, however important this purpose alone ought to be accounted. I will not say with a late subtile metaphysician,* that “ Belief consisteth in the liveliness of our ideas." That this doctrine is erroneous, it would be quite foreign to my purpose to attempt here to evince.t Thus much however is indubitable, that belief commonly enlivens our ideas; and that lively ideas have a stronger influence than faint ideas to induce belief. But so far are these two from being coincident, that even this connexion between them, though common, is not necessary. Vivacity of ideas is not always accompanied with faith, nor is faith always able to produce vivacity. The ideas raised in my mind by the Oedipus Tyrannus of Sophocles, or the Lear of Shakspeare, are incomparably more lively than those excited by a cold but faithful historiographer. Yet I may give full credit to the languid narrative of the latter, though I believe not a single sentence in those tragedies. If a proof were asked of the greater vivacity in the one case than in the other, (which, by the way, must be finally determined by consciousness,) let these effects serve for arguments. The ideas of the poet give greater pleasure, command closer attention, operate more strongly on the passions, and are longer remembered. If these be not sufficient evidences of greater vivacity, I own I have no apprehension of the meaning which that author affixes to the term. The connexion, however, that generally subsisteth between vivacity and belief will appear less marvellous, if we reflect that there is not so great a difference between argument and illustration as is usually imagined. The same ingenious writer says, concerning moral reasoning, that it is but a kind of comparison. The truth of this assertion any one will easily be convinced of, who considers the preceding observations on that subject.
Where then lies the difference between addressing the judgment, and addressing the fancy? and what hath given rise to the distinction between ratiocination and imagery? The following observations will serve for an answer to this query. It is evident, that though the mind receives a considerable pleasure from the discovery of resemblance, no pleasure is received when the resemblance is of such a nature as is familiar to every body. Such are those resemblances which result from the specific and generic qualities of ordinary objects. What gives the principal delight to the imagination is the exhibition of a strong likeness, which escapes the notice of the generality of people. The similitude of man to man, eagle to eagle, sea to
* The Author of A Treatise of Human Nature, in 3 vols.
+ If one is desirous to see a refutation of this principle, let him consult Reid's Inquiry, Ch. ii. Sect. 5.
sea, or, in brief, of one individual to another individual of the same species, affects not the fancy in the least. What poet would ever think of comparing a combat between two of his heroes to a combat between other two ? Yet nowhere else will he find so strong a resemblance. Indeed, to the faculty of imagination this resemblance appears rather under the notion of identity; although it be the foundation of the strongest reasoning from experience. Again, the similarity of one species to another of the same genus, as of the lion to the tiger, of the alder to the oak, though this too be a considerable fund of argumentation, hardly strikes the fancy more than the preceding, inasmuch as the generical properties, whereof every species participates, are also obvious. But if from the experimental reasoning we descend to the analogical, we may be said to come upon a common to which reason and fancy have an equal claim. “A comparison," says Quintilian,* “ hath almost the effect of an example.” But what are rhetorical comparisons, when brought to illustrate any point inculcated on the hearers, (what are they, I say,) but arguments from analogy? In proof of this let us borrow an instance from the forementioned rhetorician: “ Would you be convinced of the necessity of education for the mind, consider of what importance culture is to the ground : the field which, cultivated, produceth a plentiful crop of useful fruits ; if neglected, will be overrun with briars and brambles and other useless or noxious weeds.” It would be no better than trilling to point out the argument couched in this passage. Now if comparison, which is the chief, hath so great an influence upon conviction, it is no wonder that all those other oratorical tropes and figures addressed to the imagination, which are more or less nearly related to comparison, should derive hence both light and efficacy.1 Even antithesis implies comparison. Similé is a comparison in epitomé, Metaphor is an allegory in miniature. Allegory and prosopeia are comparisons conveyed under a particular form.
MEN CONSIDERED AS ENDOWED WITH MEMORY.
Farther, vivid ideas are not only more powerful than languid ideas in commanding and preserving attention, they are not only more
* Instit. lib. v. cap. 11. Proximas exempli vires habet similitudo.
| Instit. lib. v. cap. 11. Ut si animum dicas excolendum, similitudine utaris terræ, quæ neglecta sentes atque dumos, exculta fructus creat.
| Præterea, nescio quomodo etiam credit faciliùs, quæ audienti jucunda sunt, et voluptate ad fidem ducitur. Quint. L. iv. c. 2.
§ Similé and comparison are in common language frequently confounded. The difference is this: Similé is no more than a comparison suggested in a word or two; as, He fought like a lion ; His face shone as the sun. Comparison is a similé circumstantiated and included in one or more separate sentences.