410 LOGIC Ott, THE EIGHT USE OF REASON. These are very much a -kin to conditional propositions, and the truth of, them depends upon the justness of their connection. VI. Discretive propositions are such wherein various and Seemingly opposite judgments are made, whose variety or dis- tinction is noted by the particles, but, though, yet, &c. as, tra- vellers may change their climate, but not their temper : Job was patient, though his grief was great. The truth and goodness of a discretive proposition, depends on the truth of both parts, and their contrary distinction to one another ; for though both parts should be true, yet if there be no seeming opposition between them, it is an useless assertion; though we cannot call it a false one ; as, " Descartes was a phi- losopher, yet he was a Frenchman : the Romans were valiant, but they spoke Latin :" both which propositions are ridiculous for want of a seeming opposition between the parts. Since we have declared wherein the truth and falsehood of these compound propositions consist, it is proper also to give some intimations how any of these propositions, when they are false, may be opposed or contradicted. All compound propositions except copulatives and disere- tives, are properly denied or contradicted when the negation affects their conjunctive particles; as, if the disjunctive proposi- tion asserts, it is either day or night; the opponent says, it is not either day or night ; or, it is not necessary that it should be either clay or night : so the hypothetical preposition is denied, by saying, it does not follow that the earth must move if the sun be fixed. A disjunctive proposition may be contradicted also by deny- ing all the parts ; as it is neither day nor night. And a causal proposition may be denied or opposed indi- rectly and improperly, when either part of the proposition is de- nied ; and it must be false if either part be false ; but the design of the proposition being to shew the causal connection of the two parts, each part is supposed to be true, and it is not properly contradicted as a causal proposition, unless one part of it be de- nied to be the cause of the other. As for copulatives and discretives, because their truth de- pends more on the truth of their parts, therefore these may be opposed or denied, as many ways as the parts of which they are composed may be denied ; so this copulative proposition, riches and honour are temptations to pride, may be denied by saying, riches are not temptations, though honour may be : or, honour is not a temptation, though riches may be : or, neither riches nor honour are temptations, &c. So this discretive proposition, Job was patient, though his grief was great, is denied by saying, Job was not patient, though his grief was great: or, Job was patient, but his grief was not great: or, Job was not patient, nor was his grief greats
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