284 



THE SCIENCE OF LOGIC 



M is P ; S M is P ; whatever is either S or M is P : would be examples of 

 propositions with complex subjects. 



Propositions with alternative predicates Dr. Keynes would regard not as 

 &quot;compound&quot; but as &quot;simple &quot; propositions &quot;with complex terms,&quot; and as 

 equivalent to categoricals : whereas the second class of alternatives, to be 

 referred to presently, are &quot; compound&quot; and not reducible to categoricals. 

 Similarly, he regards the &quot; conditional &quot; proposition (If S is M it is P, or 

 Whenever S is M it is P, or S M is P) as a &quot; simple &quot; proposition with 

 a complex subject, and equivalent to the categorical ; while he regards the 

 &quot; pure hypothetical &quot; (If A is true C is true) as a compound proposition, not 

 so reducible. 



By means of these distinctions he leads up to a very symmetrical classi 

 fication of judgments into simple asserforic, simple modal, compound ass ertoric 

 and compound modal?- The alternative proposition will, as we shall see, be 

 best interpreted assertorically ; hypothetical we have seen to be always 

 modal ; conditionals to be usually so ; while the categorical form is the 

 natural expression of the simple assertoric judgment. Thus, we have the 



Assertorically by the Categorical pro 

 position ; 

 Modally by the Conditional Proposition ; 



Assertorically by the Alternative * pro 

 position ; 



Modally by the Hypothetical proposi 

 tion. 



SIMPLE JUDGMENT expressed 



COMPOUND JUDGMENT expressed 



As in the case of &quot; If&quot; propositions, so also here, the distinction between the 

 class called &quot;simple &quot; with alternative predicate, and that called &quot; compound,&quot; 

 is not fundamental. It may lend itself well to logical treatment, but it does not 

 remove the fundamental sameness there is in the act of judgment as such 

 whether this be expressed by a logically &quot; simple,&quot; or by a logically &quot; com 

 pound,&quot; proposition. The fact that &quot; This S is either P or Q &quot; may be 

 regarded as logically &quot; compound,&quot; while &quot; Every S is either P or Q &quot; must 

 be regarded as logically &quot;simple &quot; ; or that &quot; If this S is M it is P&quot; is 

 &quot;compound,&quot; while &quot; If any S is M it is P&quot; is &quot;simple&quot; (133 n.) : 

 shows clearly enough that the distinction is not a fundamental one, but rather 

 conventional, and established for convenience of logical treatment. 



In the sections that follow we shall have regard both to the propositions 

 which merely give alternative predicates and to those which offer a choice 

 between independent judgments. 



145. IMPORT AND FUNCTION OF ALTERNATIVE JUDGMENTS. 

 We must now determine whether in the alternative proposition 

 the alternatives are meant to be mutually exclusive : whether 

 &quot; Either X or Y&quot; is to be interpreted as &quot; Either X or Y or possibly 

 both,&quot; or as &quot; Either X or Y but not both&quot;. In many, if not in 

 most, cases, the matter or meaning will determine this question for 



*op. cit., p. 282 ; cf. supra, 83, 84. 



2 To which we may add the Renwtive, Disjunctive^ and Conjunctive or Copula 

 tive, forms. 



