200 REASONING. 



which we formerly remarked* that all propositions, and of 

 course therefore all combinations of propositions, might he 

 expressed. We observed that a proposition might be con- 

 sidered in two different lights ; as a portion of our knowledge 

 of nature, or as a memorandum for our guidance. Under the 

 former, or speculative aspect, an affirmative general proposi- 

 tion is an assertion of a speculative truth, viz. that whatever 

 has a certain attribute has a certain other attribute. Under 

 the other aspect, it is to be regarded not as a part of our know- 

 ledge, but as an aid for our practical exigencies, by enabling 

 us, when we see or learn that an object possesses one of the 

 two attributes, to infer that it possesses the other; thus em- 

 ploying the first attribute as a mark or evidence of the second. 

 Thus regarded, every syllogism comes within the following 

 general formula : 



Attribute A is a mark of attribute B, 



The given object has the mark A, 

 therefore 



The given object has the attribute B. 

 Referred to this type, the arguments which we have lately 



be denied, that if a hundred sensations are undistinguishably alike, their resem- 

 blance ought to be spoken of as one resemblance, and not a hundred resem- 

 blances which merely resemble one another. The things compared are many, 

 but the something common to all of them must be conceived as one, just as the 

 name is conceived as one, though corresponding to numerically different sensa- 

 tions of sound each time it is pronounced. The general term man does not 

 connote the sensations derived once from one man, which, once gone, can no 

 more occur again than the same flash of lightning. It connotes the general type 

 of the sensations derived always from all men, and the power (always thought 

 of as one) of producing sensations of that type. And the axiom might be thus 

 worded : Two types of sensation each of which coexists with a third type, 

 coexist with another ; or Two powers each of which coexists with a third power 

 coexist with one another. 



Mr. Spencer has misunderstood me in another particular. He supposes that 

 the coexistence spoken of in the axiom, of two things with the same third 

 thing, means simultaneousness in time. The coexistence meant is that of being 

 jointly attributes of the same subject. The attribute of being born without 

 teeth, and the attribute of having thirty-two teeth in. mature age, are in this 

 sense coexistent, both being attributes of man, though ex vi termini never of 

 the same man at the same time. 



* Supra, p. 128. 



