118. REASONING. 



dictum de omrii merely amouiits to the identical proposition, that what- 

 ever is true of certain objects, is^true of each of those objects: If all 

 ratiocination were no more than the application of this maxim to 

 particular cases, the syllogism would indeed be, what it has so often 

 been declared to be, solemn trifling. The diction de omni is on a par 

 with another truth, which in its time was also reckoned of great 

 importance, "Whatever is, is;" and not to be compared in point of 

 sionilicance to the cognate aphorism, "It is impossible for the same 

 thino- to be and not to be ;" since this is, at the lowest, equivalent to 

 the logical axiom that contradictory propositions cannot both be ti'ue. 

 To o-ive any real meaning to the dictum de omni, we must consider it 

 not as an axiom but as a definition ; we must look upon it as intended 

 to explain, in a circuitous and paraphrastic manner, the meaning of 

 the word class. 



An error which seemed finally refuted and dislodged from science, 

 often needs only put on a new suit of phrases, to be welcomed back to 

 its old quarters, and allowed to repose unquestioned for another cycle 

 of ages. Modern philosophers have not been sparing in their contempt 

 for the scholastic dogma that genera and species are a peculiar kind of 

 substances, which general substances being the only pennanent things, 

 while the individual substances comprehended under them are in a 

 perpetual flux, knowledge, which necessarily imports stability, can only 

 have relation to those general substances or universals, and not to the 

 facts or particulars included under them. Yet, though nominally re- 

 jected, this very doctrine, whether disguised under the Abstract Ideas of 

 Locke (whose speculations, however, it has less vitiated than those of 

 perhaps any other writer who has been infected with it), under the 

 ultra-nominalism of Hobbes and Condillac, or the ontology of the later 

 Kantians, has never ceased to poison philosophy. Once accustomed 

 to consider scientific investigation as essentially consisting in the study 

 of universals, men did not drop this habit of thought when they ceased 

 to regard universals as possessing an independent existence : and even 

 those who went the length of considering them as mere names, could 

 not free themselves from the notion that the investigation of truth con- 

 sisted entirely or partly in some kind of conjuration or juggle with 

 those names. Wlien a philosopher adopted fully the Nominalist view 

 of the signification of general language, retaining along with if the 

 dictum de omni as the foundation of all reasoning, two such premisses 

 fairly put together were likely, if he was a consistent thinker, to land 

 him in rather startling conclusions. Accordingly it has been seriously 

 held by Avi'iters of deserved celebrity, that the process of ari'iving at 

 new truths by reasoning consists in the mere substitution of one set of 

 arbiti-ary signs for another ; a doctrine which they supposed to derive 

 irresistible confirmation fi'om the example of algebra. If there were 

 any process in sorcery or necromancy more preternatural than this, I 

 should be much surprised. Tlie culminating point of this philosophy 

 is the noted aphorism of Condillac, that a science is nothing, or scarcely 

 anything, but une langue hien faite : in other words, that the one suflJi- 

 cient rule for discovering the nature and properties' of objects is to 

 name them properly : as if the reverse were not the truth, that it is im- 

 possible to name them properly except in proportion as we are already 

 acquainted with their nature and properties. Can it be necessary to 

 say, that none, not even the most tnvial knowledge with respect to 



