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(8) Pride is inconsistent with innocence; angels have innocence : therefore they have no pride. Or thus ; devils have pride : therefore they have not innocence.
I might multiply other instances of these connexive fyllogisms, by bringing in all sorts of exceptive, exclus live, comparative, and modal propositions into the composition of them; for all these may be wrought into conjunctive, as well as into simple syllogisms, and thereby we may render them complex. . But it would waite time and paper without equal profit.
Concerning these various kinds of conjunctive syllogisms, take these two observations.
Obferv. I. Most of them may be transformed into categorical fyllogisms by those who have a mind to prove the truth of them that way; or they may be easily converted into cach other by changing the forms of speech.
Obferv. II. These conjunctive fyllogisms are seldor deficient or faulty in the form of them; for such a deficience would be discovered at the first glance gener. ally by common reason, without any artificial rules of logic: the chief care therefore is to see that the major proposition be true, upon which the whole force of the argument usually depends.
Of compuund Sjllogisins.
which are made of two or more single lyllogiams, and may be resolved into them. The chief kinds are there, Epichirema, Dilemma, Profyllogismus, and Sorites.
I. Epichirema is a fyllogism which contains the proof of the major or minor, or both, before it draws the conclufion. This is often used in writing, in public speeches, and in common conversation, that so each part of the discourse may be confirmed and put out of doubt, as it moves on towards the conclusion, which was chiefly designed. Take this instance;
Sickness may be good for us ; for it weans us from the pleasures of life, and makes us think of dying;
But we are uneasy under sickness, which appears by our impatience, complaints, groaning : &c.
Therefore we are uneasy sometimes under that which is good for us.
Another instance you may fee in Cicero's oration in defence of Milo, who had flain Clodius. His major proposition is, that it is lawful for one man to kill as nother who lies in wait to kill him; which he proves from the custom of nations, from natural equity, examples, &c. his minor is, that Clodius laid wait for Milo; which he proves by his arms, guards, &c. and then infers the conclusion, that it was lawful for Milo to kill Clodius.
II. A Dilemma 'is an argument which divides the vwhole into all its parts or members by a disjunctive propofition, and then infers something concerning each part which is finally inferred concerning the whole. Instances of this are frequent; as, in this life we must either obey our vicious inclinations or resist them; to obey them will bring fin and forrow, to resist them is laborious and painful : therefore we cannot be perfectly free from sorrow or pain in this life.
A Dilemma becomes faulty or ineffectual three ways; first, when the nembers of the division are not well opposed, or not fully enumerated; for then the major is false. Secondly, when what is afferted concerning each part is not just; for then the minor is not true. Thirdly, when it may be retorted with equal force upon him who utters it.
There was a famous ancient instance of this case wherein a Dilemma was retorted. Euathlus promised Protagoras a reward when he had taught him the art of pleading, and it was to be paid the firit day that he gained any cause in the court, After a considerable time Protagoras goes to law with Euathlus for the re: Waid, and utes this Dilemma; either the cause will 50
on my side, or on yours; if the cause goes on my side, you must pay me according to the fentence of the judge: if the cause goes on your side, you must pay me according to your bargain : therefore whether the cause
goes for me or againit me, you must pay me the reward. But Euathlus retorted this Dilemma thus : Either I fhall gain the cause or lose it; if I gain the cause, then nothing will be due to you, according to the sentence of the judge; but if I lose the cause, nothing will be due to you according to my bargain : therefore whether I gain or lose the cause, I will not pay you, for nothing will be due to you.
Note 1. A Dilemma is usually described as though it always proved the absurdity, inconvenience, or unreasonableness of some opinion or practice ; and this is the most common design of it; but it is plain, that it may also be used to prove the truth or advantage of any thing proposed ; as, in heaven we shall either have desires or not; if we have no desires, then we have full satisfaction ; if we have desires, they shall be satisfied as fast as they arise : therefore in heaven we thall be compleatly satisfied.
Ncte 2. This fort of argument may be compofed of three or four members, and may be called a TriJernma.
III. A Profyllogism is when two or more syllogisms are so connected together, that the conclusion of the former is the major or the minor of the following :'as, blood cannot think ; but the soul of man thinks : there. fore the soul of man is not blood ; but the soul of a brute is his blood, according to the scripture; therefore the soul of man is different from the soul of a brute. See another instance in the introduction to this treatise, p. 3.
IV. A Sorites is when feveral middle terms are chosen to connect one another succefsively in several propositions, till the last proposition connects its predicate with the first subject. Thus, all men of revenge have their fouls often uneasy: uneasy fouls are a plague to themselves ; now to be one's own plague is folly in the extreme; therefore all men of revenge are extreme: fools.
The apostle, Rom. viii. 29. gives us an instance of this fort of argument, if it were reduced to exact form : Whom he foreknew those he predestinated; whom he predestinated he called; whom he called he justified: whom he justified he glorified: therefore whom he foreknew he giorified.
To these fyllogisms it may not be improper to add Induction, which is when from several particular propositions we infer one general; as, the doctrine of the Socinians cannot be proved from the Gospel, it cannot be proved from the acts of the Apostles, it cannot be proved from the Epirtles, nor the book of Revelation ; therefore it cannot be proved from the New Testament.
Nite, This fort of argument is often defective, because there is not due care taken to enumerate all the particulars on which the conclution should depend.
All these four kinds of fyllogisms in this section may be called redundant, because they have more then three propofitions. But there is one fort of syllogifin which is defective, and is called an Enthymema, because only the conclufion with one of the premifes is exprefled, while the other is fuppofed and referved in the mind : thus, there is no true religion without good morals : therefore a knave cannot be truly religious; or thus, it is our duty to love our neighbours as ourselves : there. fore there are but few who perform their duty.
Note. This is the most common sort of argument amongít mankind both in writing and in speaking ; for it would take up too much time and too much retard the discourse to draw out all our arguments in mode and figure. Besides, mankind love to have fo much compliment paid to their understandings, as to suppose that they know the major or minor which is fupprefied. and implied, when you pronounce the other premise and the conclusion.
If there be any debate about this argument, the syllo. gism must be compleated, in order to try its force and goodness, by adding the absent proposition..
Of the middle Terms, of common Places or Topics, and
Invention of Arguments.
TT HE next division of fyllogifms is according to the
middle term, which is made use of in the proof of any propofition. Now the middle term (as we have hinted before) is often called Argument, because the force of the syllogism depends upon it: we must make a little delay here to treat briefly of the doctrine of topics, or places whence middle terms or arguments are drawn.
All arts and sciences have some general subjects which belong to them, which are called Topics or common places; because middle terms are borrowed, and arguments derived from them for the proof of their various propositions which we have occasion to discourse of. The topics of Grammar, are etymology, noun, verb, construction, fignification, &c. The topics of Logic are genus, fpecies, difference, property, definition, divilion, &c. The topics of Ontology or Metaphysics, are cause, effect, action, passion, indentity, opposition, fubject, adjunct, fign, &c. The topics of Morality or Ethics, are law, fin, duty, authority, freedom of will, command, threatning, reward, punishment, &c. The topics of Theology, are, God, Christ, faith, hope, worthip, falvation, &c.
To these several topics there belong particular obfervations, axioms, canons, or rules*, which are laid down in their proper sciences ; as,
Grammar hath fuch canon, (viz.) words in a different construction obtain a different sense, words derived from the same primitive may probably have some affinity in their original meaning, &c.
Canons in logic are such as these; every part of a division, fingly taken must contain less than the whole. A definition must be peculiar and proper to the thing.
* A canon is a proposition declaring some property of the fub. ject which is not expressed in the definition or division of it.