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But when it concludes also the way and manner wherein the predicate is connected with the subject, it is called a modal proposition; as, when I say, it is necessary' that a true christian should be an honest man.
Logical writers generally make the modality of this proposition to belong to the copula, because it fhews the manner of the connection between subject and
predicate. But if the form of the sentence as a logical propofition be duly considered, the mode itself is the very predicate of the propofition, and it must run thus : that a true christian should be an honest man is a necessary thing, and then the whole primary proposition is included in the subject of the modal propofition.
There are four modes of connecting the predicate with the subject, which are usually reckoned up on this occafion (viz.) Neceflity and contingency which are two opposites, poflibility and impoflibility which are allo two opposites ; as, it is necessary that a globe should be round ; that a globe be made of wood or glass is an unnecessary or contingent thing : it is impossible that a globe should be square : it is impofsible that a globe Ihould be of water.
With regard to the modal propositions which the schools have introduced, I would make these two remarks:
Remark 1. These propositions in English are formed by the resolution of the words, must be, might not be, can be, and cannot be, unto those more explicate forms of a logical copula and predicate, is necessary, is contingent, is poslīble, is impossible ; for it is necessary that a globe fhould be round, fignifies no more than that a globe must be round.
Remark 2. Let it be noted that this quadruple modality is only an enumeration of the natural modes or manners wherein the predicate is connected with the subject : we might also describe several moral and civil modes of connecting two ideas together (viz.) lawfulness and unlawfulnels, conveniency and inconveniency, &c. whence we may form such modal propositions as these. It is unlawful for any person to kill an innocent man: it is unlawful for christians to eat flesh in lent; to tell all that we think is inexpedient : for a
man to be affable to his neighbour is very convenient, Ecc.
There are several other modes of speaking whereby a predicate is connected with a subject : fuch as, it is certain, it is doubtful, it is probable, it is improbable, it is agreed, it is granted, it is said by the ancients, it is written, &c. all which will form other kinds of modal propofitions.
But whether the modality be natural, moral, Es. yet in all these propositions it is the mode is the proper predicate, and all the rest of the propofition, except the copula (or word is) belongs to the subject; and thus they become pure propofitions of a complex nature, of which we shall treat in the next fection, so that there is no great need of making modals a distinct fort.
There are many little subtleties which the schools acquaint us with concerning the conversion and oppofition and equipollence of these modal propositions, suited to the Latin or Greek tongues rather than the English, and fit to pass away the idle time of a ftudent, rather than to enrich his understanding.
7 HEN we consider the nature of propofitions,
together with the formation of them, and the materials whereof they are made, we divide them into fingle and compound.
A single propofition is that which has but one subject and one predicate , but if it has more subjects or more predicates, it is called a compound propofition, and it contains two or more propofitions in it.
A single propofition (which is also called categorical) may be divided again into simple and complex*.
* As simple ideas are opposed to complex, and single ideas to compound, to propositions are distinguished in the same manner ; the
A purely fimple proposition is that whose subject and predicate are made up of single terms ; as, virtue is de sirable : every penitent is pardoned; no man is innocent.
When the subject or predicate, or both, are made up: of complex terms, it is called a complex proposition ; as, every sincere penitent is pardoned ; virtue is desirable for its own fake ; no man alive is perfectly innocent.
If the term which is added to the subject of a coinplex proposition be either effential or any way neceffary to it, then it is called explicative, for it only explains the subject; as every mortal man is a fon of Adam. But if the term added to make up the complex subject does not necessarily or constantly belong to it, then it is: determinative, and limits the subject to a particular part of its extension; as, every pious man shall be happy. In the first proposition the word' mortal is merely explicative : in the second proposition the word pious is determinative.
Here note, that whatsoever may be affirmed or denied concerning any subject, with an explicative addition, may be also affirmed or denied of that lubject withoirt it; as we may boldly say, every man is a fon of Adam, as well as every mortal man: but it is not so, where the addition is determinative, fo we cannot say, every man shall be happy, though every pious man shali be fo.
In a complex proposition the predicate or subject is sometimes made complex by the pronouns who, which, whose, to whom, &c, which make another proposition ; as every man who is pious, shall be saved : Julius, whose sirname was Cæsar, overcame Pompey : bodies, which are transparent, have many pores. Here the whole proposition is called the primary or chief, and the additional proposition is called an incident proposition. But it is itill to be esteemed in this case merely as a part of the complex term; and the truth or falta hood of the whole complex proposition is not to be English tongue in this respect having some advantage above the learn... ed languages, which have no usual wurd to diitin, united single from fimple.
judged by the truth or falfhood of the incident proposition, but by the connection of the whole fubject with the predicate. For the incident proposition may be false, and absurd, or impossible, and yet the whole complex proposition may be true, as a horse, which has wings, might fly over the Thames.
Beside this complection which belongs to the subject or predicate, logical writers ule to say, there is a complection which may fail upon the copula alfo; but this . I have a counted for in the section concerning modal propositions; and indeed it is not of much importance whether it were placed there or here.
COMPOUND proposition is made up of two or
more subjects or predicates, or both ; and it contains in it two or more propositions, which are either plainly exprefd, or concealed and implied.
The firit fort of compound propositions are those wherein the composition is expressed and evident, and they are distinguished into these six kinds, (viz.) copus larive, disjunctive, conditional, causal, relative and dise cretive.
I. Copulative propositions are those which have more fubjects or predicates connected by affirmative or negative conjuctions.; as, riches and honours are temptaá tions to pride; Cæfar conquered the Gauls and the Britons ; neither gold nor jewels will purchase immor. tality. These propositions are evidently compounded, for each of them may be resolved into two propositions, (viz). riches are temptations to pride, and honour is a temptation to pride; and fo the rest.
The truth of. copulative propositions depends upon the truth of all the parts of them ; for if Cæfar had
conquered the Gauls, and not the Britons, or the Britons and not the Gauls, the second copulative proposition had not been true.
Here note, those propositions, which cannot be refolved into two or more fimple propositions, are 110t properly copulative, though two or more ideas be connected and coupled by such conjunctions, either in the fubject or predicate: as, two and three make five :majesty, and meekness do not often meet: the sun, moon, and stars are not all féen at once. positions are to be esteemed merely complex, because the predicate cannot be affirmed of each single subject, but only of all of them together as a collective subject.
II. Disjunctive propofitions are when the parts are disjoined or opposed to one another by disjunctive para ticies ;, as, it is either day or night : the weather is. either shining or rainy:: quantity is either length, breadth or depth.
The truth of disjunctives depends on the necessary and immediate opposition of the parts; therefore only the last of these examples is true : but the two first are not strictly true, because twilight is a medium between day and night; and dry, cloudy weather is a medium between shining and rainy.
III. Conditional or hypothetical propositions are those whose parts are united by the conditional particle if.; as,, if the fun be fixed, the earth mult move :. if there be no fire, there will be no smoke..
Note, the first part of these propositions, or that wherein the condition is contained, is called the antece dent, the other is called the consequent.
The truth of these propositions depends not at all on the truth and fallhood of their two parts, but on the truth of the connection of them ; for each part of them. may be falle, and yet the whole proposition true; as, if there be no providence, there will be no future judgment.
IV. Caufal propositions are where two propositions. are joined by caulal particles : :as, houses were not built that they might be deltroved : Rehoboam was unhappy. because he followed evil nel. The truth of a causal p- i ition arifes not from the