NAMES AND PROPOSITIONS. 



they convey information, not already involved in the 

 names employed. When I am told that all, or even 

 that some objects, which have certain qualities, or 

 which stand in certain relations, have also certain other 

 qualities, or stand in certain other relations, I learn 

 from this proposition a new fact ; a fact not included 

 in my knowledge of the meaning of the words, nor 

 even of the existence of Things answering to the signi- 

 fication of those words. It is this class of propositions 

 only which are in themselves instructive, or from 

 which any instructive propositions can be inferred. 



Nothing has probably contributed more to the 

 opinion so commonly prevalent of the futility of the 

 school logic, than the circumstance that almost all 

 the examples used in the common school books to 

 illustrate the doctrines of predication and of the syllo- 

 gism, consist of essential propositions. They were 

 usually taken either from the branches or from the 

 main trunk of the Predicamental Tree, which included 

 nothing but what was of the essence of the species : 

 Omne corpus est substantia, Omne animal est corpus, 

 Omnis homo est corpus , Omnis homo est animal, Omnis 

 homo est rationalis, and so forth. It is far from won- 

 derful that the syllogistic art should have been thought 

 to be of no use in assisting correct reasoning, when 

 almost the 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 comprehended the meaning of the words ; 

 and stood exactly on a level, in point of evidence, 

 with the premisses from which they were drawn. I 

 have, therefore, throughout this work, studiously 

 avoided the employment of essential propositions as 

 examples, except where the nature of the principle to 

 be illustrated specifically required them. 



