Authors/Ockham/Summa Logicae/Book II/Chapter 37

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Latin English
[2.37 DE PROPOSITIONIBUS IN QUIBUS CONIUNCTIONES VEL ADVERBIA PONUNTUR INTER DUOS TERMINOS] 37: On Propositions in which Conjunctions or Adverbs are Put between Two Terms
Praedictis autem est adiciendum quod quando aliqua praedictarum coniunctionum vel adverbiorum ponitur inter duos terminos, ita quod propositiones categoricae non complete exprimuntur, talis propositio est distinguenda secundum compositionem et divisionem, quia potest esse categorica vel hypothetica. Vel talis distinguenda est secundum amphiboliam, eo quod potest esse categorica vel hypothetica. Et forte ista distinctio est planior et magis propria. Tamen sive distinguatur secundum compositionem et divisionem sive secundum amphiboliam, sensus non diversificatur. Unde ubi ponitur haec coniunctio 'vel' illa propositio est distinguenda, eo quod potest esse disiunctiva vel de disiuncto extremo. Sicut haec est distinguenda 'omnis homo salvabitur vel damnabitur', eo quod potest esse disiunctiva, et tunc aequivalet isti 'omnis homo salvabitur vel omnis homo damnabitur', quae falsa est; vel potest esse de disiuncto extremo, et tunc aequivalet isti 'de quolibet contento sub homine verificatur hoc totum: salvabitur vel damnabitur'; et hoc est verum, et ideo prima est vera. To the previous points it should be added that when one of the conjunctions or adverbs occurs between two terms,so that the categorical propositions are not completely expressed, such a proposition should be distinguished according to composition and division, because it can be a categorical proposition or a hypothetical proposition.

Or such a proposition must be distinguished as amphibolous, in that it can be categorical or hypothetical. And perhaps this distinction is clearer and more proper. Yet whether it is distinguished according to composition and division or according to amphiboly, the sense is not diversified.

Hence, where the conjunction 'or' occurs, the proposition must be distinguished, in that it can be a disjunctive proposition or one with a disjunct extreme. For example, the proposition 'every man will be saved or damned' should be distinguished, in that it can be disjunctive, and then it is equivalent to 'every man will be saved or every man will be damned', which is false, or it can be a proposition with a disjunct extreme, and then it is equivalent to 'the whole expression will be saved or damned is verified of everything contained under man', and this is true and so the original is true.

Et est advertendum quod quando talis propositio est singularis, tunc disiunctiva et de disiuncto praedicato aequipollent, non autem quando est universalis, ut patet in praedicto exemplo. And it should be noted that when such a proposition is singular, then the disjunctive proposition and the one with a disjunctive predicate are equipollent, but this is not so when the proposition is universal, as is clear from the above example.
Similiter, ubi ponitur haec coniunctio 'et' illa propositio est distinguenda, eo quod potest esse copulativa vel de copulato extremo, sicut ista est distinguenda 'tria et duo sunt quinque': si sit de copulato subiecto, vera est; si sit copulativa, falsa est. Likewise, where the conjunction 'and' occurs, the proposition has to be distinguished, in that it can be a copulative proposition or a proposition with a copulative extreme. For example, the proposition 'three and two are five' has to be distinguished. If it is a proposition with a copulative subject, it is true. If it is a copulative proposition, it is false.
Similiter est de tali propositione ubi panitur haec coniunctio 'si' quod talis propositio est distinguenda, eo quod potest esse condicionalis vel de condicionato extremo, sicut ista 'omne possibile, si est necessarium, est verum' est distinguenda, eo quod potest esse condicionalis, et tunc est sensus 'si omne possibile est necessarium, omne possibile est verum', quod verum est; si sit de condicionato subiecto, tunc aequivalet isti: de omni illa de quo verificatur hoc totum 'possibile, si est necessarium', verificatur hoc praedicatum 'verum'. Et hoc est falsum. Nam de ista propositione 'homo est asinus' verificatur hoc totum 'possibile, si est necessarium'. Haec enim est vera 'te esse asinum est possibile, si est necessarium', sive sit condicionalis sive de condicionato subiecto, et tamen haec non est vera 'te esse asinum est verum' It is similar for such a proposition where it contains the conjunction 'if'. Such a proposition must be distinguished, in that it can be a conditional proposition or a proposition with a conditional extreme. For example, 'everything possible, if it is necessary, is true' must be distinguished, in that it can be conditional, and then the sense is, if everything possible is necessary, everything possible is true', which is true. If it is a proposition with a conditional subject, then it is equivalent to 'the predicate "true" is verified of everything of which the whole expression "possible, if it is necessary" is verified'. And this is false. For the whole expression 'possible, if it is necessary' is verified of the proposition 'A donkey is a man'. For this is true: 'that you are a donkey is possible, if it is necessary', whether it is a conditional proposition or a proposition with a conditional subject. And yet 'that you are a donkey is true' is not true.
Similiter est de coniunctione causali, quod propositio in qua ponitur est distinguenda, eo quod potest esse causalis vel de causali extremo. Sicut ista est distinguenda 'omnis homo est capax Dei, quia habens animam rationalem', eo quod potest esse causalis vel de causali praedicato. Sed semper vel frequenter illi sensus convertuntur. It is similarly the case for a causal conjunction, that the proposition in which it occurs must be distinguished, in that it can be a causal proposition or a proposition with a causal extreme. For example, 'every man has a capacity for God because he has a rational soul' must be distinguished, in that it can be a causal proposition or a proposition with a causal predicate. But these two senses are always or frequently convertible.
Similiter, ubi ponitur adverbium temporis, illa propositio est distinguenda, eo quod potest esse temporalis vel de temporali extremo. Sicut ista est distinguenda 'omnis damnatus, dum fuit viator, peccavit', eo quod potest esse temporalis vel de temporali praedicato. Si sit temporalis, tunc aequivalet isti 'dum omnis damnatus fuit viator, omnis damnatus peccavit', quae falsa est, quia istae duae numquam fuerunt simul verae; si sit de temporali extremo, tunc aequivalet isti 'de quolibet damnato verificatur hoc totum: dum fuit viator, peccavit', et hoc est verum, quia quaelibet singularis est vera. Likewise, when a temporal adverb occurs, the proposition must be distinguished, in that it can be a temporal proposition or a proposition with a temporal extreme.

For example, the proposition 'everyone damned, while he was a wayfarer, sinned' must be distinguished, in that it can be a temporal proposition or a proposition with a temporal predicate.

If it is a temporal proposition, then it is equivalent to 'while everyone damned was a wayfarer, everyone damned sinned', which is false, because the two parts have never been true at the same time. If it is a proposition with a temporal extreme, then it is equivalent to 'the whole expression "sinned while he was a wayfarer" is verified of everyone who is damned', and this is true, because each singular is true.

Similiter est de adverbio locali. Sicut patet de ista 'omnis homo currebat, ubi disputabat'. Panatur enim quod quilibet homo in eodem loco in quo disputabat, currebat, sed diversi in diversis. Tunc patet quod prima est vera, si sit de locali praedicato; et falsa, si sit localis. It is similarly the case for a local adverb, as is clear from 'every man was running where he was disputing'. For it is given that every man was running in the same place where he was disputing, but different men in different places. Then it is clear that the first is true if it is a proposition with a local predicate, and false if it is a local proposition.
Est etiam sciendum quod talis distinctio non tantum habet locum in praedictis, sed etiam consimilis distinctio potest poni quando hoc pronomen 'qui' ponitur inter duos terminos. Sicut hic 'omnis homo, qui est albus, currit', nam in sensu divisionis aequivalet uni copulativae, isti scilicet 'omnis homo currit et ille est albus'; in sensu compositionis denotatur quod de quocumque verificatur hoc totum 'homo, qui est albus', de illa verificatur hoc praedicatum 'currit'. It should also be known that such a distinction not only has a place in what was said above,but also the same distinction can be given when the pronoun 'who' is put between two terms. For example, in 'every man, who is white, is running', for in the sense of division it is equivalent to a copulative proposition, namely, 'every man is running and he is white'. In the sense of composition it is denoted that the predicate 'runs' is verified of everything of which the whole expression 'man who is white' is verified.
Et de propositionibus ad praesens ista sufficiant. And these points about propositions should suffice for the present.

Notes