VERBAL AND REAL TROPOSITIONS. 79 



that the syllogistic art shovikl have been thought to be of no use in 

 assisting coiToct reasoning, when almost tlie only propositions which, 

 in the hands of its professed teachers, it was employed to prove, were 

 such as every one assented to without proof the moment he compre- 

 hended the meaning of the words : and stood exactly on a level, in 

 point of evidence, with the premises fi-om which they were drawn. I 

 have, therefore, throughout this work, studiously avoided the employ- 

 ment of essential propositions as examples, except where the nature of 

 the principle to be illustrated specifically required them. 



§ 5. With respect to propositions which do convey information, 

 which assert something of a Thing, under a name that does not already 

 presuppose what is about to be asserted, there are two different aspects 

 in which these, or rather such of them as are general propositions, may 

 be considered : we may either look at them as portions of specula- 

 tive ti-uth, or as memoranda for practical use. According as we con- 

 sider propositions in one or the other of these lights, their import may 

 be conveniently expressed in one or in the other of two formulas. 



According to the formula which we have hitherto employed, and 

 which is best adapted to express the import of the proposition as a 

 portion of our theoretical knowledge. All men are mortal, means that 

 the attributes of man are always accompanied by the attribute mor- . 

 tality : No men are gods, means that the attributes of man are never 

 accompanied by the attributes, or at least never by all the attributes, 

 of a god. But when the proposition is considered as a memorandum 

 for practical use, we shall find a different mode of expressing the same 

 meaning better adapted to indicate the oflfice which the proposition 

 pei'foiTns. The practical use of a proposition is to apprise or remind 

 us what we have to expect in any individual case which comes within 

 die assertion contained in the proposition. In reference to this pui'- 

 pose, the proposition, All men are mortal, means that the attributes of 

 man are evidence of, are a marJc of, mortality ; an indication by which 

 the presence of that attribute is made manifest. No men are gods, 

 means that the atti'ibutes of man are a mark or evidence that some or 

 all of the attributes of a god are not there ; that where the fonner are, 

 we need not ex])ect to find the latter. 



These two forms of expression are at bottom equivalent ; but the 

 one points the attention more directly to what a jjroposition means, the 

 latter to the manner in which it is to be used. 



Now it is to be observed that Reasoning (the subject to which we 

 are next to proceed) is a process into which propositions enter not as 

 ultimate results, but as means to the establishment of other proposi- 

 tions. We may expect, therefore, that the mode of exhibiting the 

 import of a general proposition which shows it hi its application to 

 practical use, will best express the fimction which propositions per- 

 form in Reasoning. And accordingly, in the theory of Reasoning, the 

 mode of vie\\dng the subject wliich considers a Proposition as asserting 

 that one fact or phenomenon is a marh or evidence of another fact or 

 phenomenon, will bo found almost indispensa])le. Ff)r tlie purposes 

 of tliat Theory, the best mode of defining the import of a proposition 

 is not the mode which shows the most clearly what it is in itself, but 

 that which most distinctly suggests the manner in which it may be 

 made available for advancing from it to other propositions. 



