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ple and short sentences till we have acquired facility in the management of them.
Obs.- The best exercise in writing and speaking is to read a short story; and then write or speak it, in our own phraseology. Such an exercise continued every day for two years, one day writing and the other day speaking, would teach the arts of spelling, writing, and speaking, at the same instant.
414. We should avoid all quaint phrases, cant words, vulgar proverbs, and foreign idioms; and make our choice from the phraseology of the Old or New Testaments, the works of Addison or Shakespeare; and avoid the latinized phraseology of Johnson, and the Gallic phraseology of some other modern writers.
Obs.--Happily, the translation of the Bible has served to preserve our language ; or it would have been lost amidst the barbarous affectations of Johnson and his followers. We have no where such variety of beautiful and affecting language as in the Old and New Testaments; and these, and the works of our immortal Shakespeare, will, I hope, preserve our language from the corruptions and innovations daily making in it, by those who prefer sound to sense.
415. To speak or write our ideas in an able and persuasive manner, we ought to possess ourselves of various knowledge; to read the best books on all subjects ; to suffer no hour to pass, without making some improvement; and think, talk, and write ourselves on subjects, on which we have perused the opinions of others.
416. We should commit to memory the terms and leading facts of the various Arts and Sciences; and frequently reduce to writing, striking facts or important sentiments which we meet with in reading. We should compare one author with another on the same subject; and frequently converse with others, on any points in which authors do not satisfy our curiosity.
Obs. Dr. Irving's Elements of Composition is a library for young persons; and the study of it should follow that of ev: ery grammar. Adair's Questions render it practical for schools.
XVII. Logic. 417. Logic is that important and useful art, which teaches the art of correct thinking. The lógicians give five general rules, by which to assist our views in thinking, writing and speaking on all subjects.
As these rules are of great and constant use, I have copied them from my own English Grammar:
a. Conceive of things clearly and distinctly, in their own natures.
Obs.—That is, we should acquire a clear and distinct conception of things as they are in their own nature; and not be content with obscure and confused ideas, when clearer are to be attained.
b. Conceive of things completely, in all their parts.
Obs—There is a metaphysical or ideal whole, a mathematical or integral whole, and a physical or estential whole.
c. Conceive of things comprehensively, in all their properties and relations.
Obs. That is, we must consider them in all their modes, attributes, properties, and relations; in order to attain a comprehensive view of their essential modes or attributes, and of their various occasional properties, accidental modes, and reJations.
d. Conceive of things extensively, in all their kinds.
Obs.-That is, we must search out the various species, or special natures, which are contained under the subject as a genus or general nature: as, if we would know the nature of an animal perfectly, we must take cognizance of beasts, birds, fisbes, and insects, as well as men; all which are contained under the general nature and name of animal.
e. Conceive of things in order, or in a proper method.
Obs. That is, we should rank and place our ideas in a prop. er method and just order. We must not conceive of things in a confused heap: but dispose our ideas in some method, which may be easy and useful for the understanding and memory.
418. Method is analytical or synthetical. Analytical method resolves the compound into its principles, and the whole into its parts. Synthetical, begins with the parts and leads to a whole, or it puts together the principles and forms a compound.
419. Arguments are either metaphysical, physical, political, moral, mechanical, or theological, according to the science or subject from which they are drawn. The following deserve notice :
a The Argumentum ad judicium, is an appeal to the common sense of mankind.
b. The Argumentum ad fidem, is an appeal to the faith.
c. The Argumentum ad hominem, is an appeal to the practices or professed principles of the adversary.
d. The Argumetum ad populum, is an appeal to the people.
e. The Argumentum ex concesso, is when something is proved by means of some proposition previously conceded. f. The Argumentum ad passiones, is an appeal to the
g. The Argumentum a fortiori, proves the conclusion, by proving a less probable proposition on which the conclusion depends.
h. The Argumentum ad ignorantiam, is founded upon insufficient principles, which the opponent has not skill to refute.
i. Argumentum ad verecundium, is drawn from authority we are ashamed to dispute.
k. A direct argument is that which immediately proves the proposition in question.
1. An indirect argument proves the conclusion, by proving or disproving some proposition upon which the conclusion depends.
420. Certainty or Truth is of several kinds : there is a mathematical certainty, which admits of demonstration; a moral certainty, which is derived from testimony; a physical certainty, derived from 'the evidence of the senses and the course of nature; and a theological certainty, founded on the doctrines of the Scriptures.
421. Evidence is of different kinds; as the evidence of sense, founded on the perceptions of our senses.
The evidence of intuition, founded on self-evident axioms; as that the whole is greater than a part, or, that every effect is produced by some cause.
The evidence of reason, founded on clear and in
dubitable deductions from well-founded premises and doctrines.
And the evidence of faith, deduced from the testimony of others.
422. Demonstrations are a succession of connected propositions, beginning with self-evident truths and advancing to remoter ones.
A Demonstration a priori, is when the effect is proved by referring to the cause.
A Demonstration a posteriori, is when the cause is inferred from the effects.
Obs.--COROLLARIES are self-evident inferences from established propositions.
423. Sophistry is false reasoning, founded on false premises, or on ambiguity of terms.
Obs.-As most of the evils which exist in society grow out of sophistry, no art is more important than that which enables us to detect or expose it. The crimes of courts and wicked ministers usually escape punishment, from the effect of sophistry; and there would be few or no wars, if sophistry did not triumph in the statements of the parties.
A Sophism of Composition, is when we infer that of any thing in an aggregate or compounded sense, which is only true in a divided sense.
A Sophism of Division, is when we infer any thing in a divided sense which is only true in a compounded sense.
A Sophism of equivocation, is when we use words of an ambiguous or double sense, and draw inferences in one sense, of which the proposition is capable only in the other.
424. A petitio principii, or begging the question, is the supposition of what is not granted, or a supposed proof, by stating the question in other words.
The reductio ad absurdum, is when the truth of a proposition is proved by shewing the absurdity of a contrary supposition.
425. Induction consists in distributing a general idea into its species, and ascribing to the whole the property found in the species.
A false induction, is when general deductions are made from too limited a number of experiments or facts.
The fallacia accidentis, is when we draw inferences in regard to the nature of a thing, from circumstances only temporary or accidental.
The ignorantia elenchi, is a mistake of the question, or when one thing is proved instead of another.
Analogy is an argument in which, from corresponding causes, are deduced corresponding effects.
Obs.--The sources of errors are, (1.) The want of diligence in investigation. (2.) Judging of things by their external appearances only. (3.) Not separating the good and bad qualities that pervade the same thing, but forming a hasty judgment. (4.) Comparing things with our own situation in life; or as they happen to affect us. (5.) Associating an idea with something disagreeable, or the contrary. (6.) Prejudices formed in our infancy. (7) Giving credit to the assertions or misrepresentations of others, without inquiring into their motives, as in news-writers and reviewers; and (8.) Submitting to the force and influence of custom and fashion.
426. A Syllogism is a sentence made up of three propositions, so disposed, as that the last is necessarily inferred from those that precede it.
Every Syllogism contains two premises and a conclusion; or a major and a minor proposition and a consequence.
Example of a Syllogism :
427. An Argument is a series of syllogisms; and, although argumenys do not retain their syllogistic form in ordinary discourse, yet all arguments may be reduced to syllogisms; and errors or sophisms may thus be detected.
428. Formerly Logic, or the art of reasoning, was almost the sole business of a university education ;