260 THE SCIENCE OF LOGIC 



&quot; No person condemned for witchcraft in the reign of Queen Anne 

 was executed &quot; . 



Particulars. Particular propositions, whether affirmative or 

 negative, almost invariably carry with them, in ordinary usage, if 

 not an implication, at least an assumption, of the existence of 

 their subjects. The reason is that these judgments are almost 

 invariably based on observation of actually existing instances. 

 And a very natural way for asserting the existence of some class 

 is by means of the particular proposition. We assert the existence 

 of a class of cattle without horns by saying &quot; Some cattle have no 

 horns&quot;. 



129. CHOICE OF ALTERNATIVE INTERPRETATIONS. It 

 would appear, then, that we should not be departing very much 

 from popular usage by interpreting particulars as implying, or 

 assuming, the existence of their subjects. If, in any case, we 

 wished to avoid this implication, we might say &quot; If there be any 

 S s, some of them are (or are not) P &quot;. 



In interpreting universals as never implying, or assuming, the 

 existence of their subjects, we should, no doubt, be departing 

 somewhat more from ordinary usage ; but the advantages to be 

 gained from making this supposition in processes of inference 

 would seem to compensate for the disadvantages of such a de 

 viation. 1 



We have already seen that this supposition regarding uni 

 versals and particulars is the only one among those considered 

 which leaves the most important form of opposition, namely, 

 contradictory opposition, valid ; 2 and that it also leaves the validity 

 of the two most important eductions, namely, simple conversion 

 and simple contraposition, untouched. Of course, the fact that 

 A and E may be true together, and the fact that I and O may be 

 false together, on this assumption, will be a drawback from the 

 point of view of logical convenience. But the fact that I cannot 

 be inferred from A, nor O from E, merely renders unlawful what 

 is a useless inference in any case, while it gives the particulars 

 a locus standi of their own, independently of the universals. 



Finally, the present assumption is the only one which makes 

 each of the propositions A, E, I, and O, a simple categorical pro 

 position, containing one statement only : viz. that there are (or 



1 Cf. KEYNES, op. cit., pp. 239 sqq. 



3 Except the converse supposition referred to in 125, and the independent 

 assumption outside the import that S, etc., exist. 



