CLASSIFICATION OF FALLACIES. 



4S7 



We have thus five distinguishable I pressed in the following synoptic 

 classes of fallacy, which may be ex- J table :^ — 



'of Simple Inspection i. Fallacies a priori. 



Fallacies { 



distinctly I Fallacies 1 3- 



j Deductive \ 

 V Fallacies j *' 



conceived 



from evidence ) 



indistinctly ■ 



of Inference^ ^ conceived ) 



ij 3. We must not, however, expect 

 to find that men's actual errors always, 

 or even commonly, fall so unmi.stak- 

 ably under some one of these classes 

 as to be incapable of being referred 

 to any other. Erroneous arguments 

 do not admit of such a shai-ply cut 

 division as valid ai-guments do. An 

 argument fully stated, with all its 

 steps distinctly set out, in language 

 not susceptible of misunderstanding, 

 must, if it be erroneous, be so in some 

 one of these five modes unequivocally : 

 or indeed of the first four, since the 

 fifth, on such a supposition, would 

 vanish. But it is not in the nature 

 of bad reasoning to express itself thus 

 unambiguously. When a sophist, whe- 

 ther he is imposing on himself or 

 attempting to impose on others, can 

 be consti-ained to throw his sophistry 

 into so distinct a form, it needs, in a 

 large proportion of casej?, no further 

 exposure. 



In all arguments, everywhere but 

 in the schools, some of the links are 

 suppressed ; d fortiori when the ar- 

 guer either intends to deceive, or is 

 a lame and inexpert thinker, little 

 accustomed to bring his reasoning 

 processes to any test : and it is in 

 those steps of the reasoning which 

 are made in this tacit and half-con- 

 scious, or even wholly unconscious 

 manner, that the error oftenest lurks. 

 In order to detect the fallacy, the pro- 

 position thus .silently assumed must 

 be supplied ; but the reasoner, most 

 likely, has never really asked himself 

 what he was assuming : his confuter, 

 unless permitted to extort it from him 

 by the Socratic mode of interrogation, 



Fallacies of Observation. 

 Fallacies of Generalisation. 



Fallacies of Ratiocination. 



Fallacies of Confusion. 



must liiniself judge what the sup- 

 pressed premise ought to be in order 

 to support the conclusion. And hence, 

 in the words of Archbishop Whately, 

 " it must be often a matter of doubt, 

 or rather of arbitrary choice, not only 

 to which genus each kind of fallacy 

 should be referred, but even to which 

 kind to refer anyone individual fal- 

 lacy ; for since, in any course of argu- 

 ment, one premise is usually suppressed, 

 it frequently happens in the case of a 

 fallacy, that the hearers are left to the 

 alternative of supplying either a pre- 

 mise which is not true, or ehe one 

 which does not prove the conclusion : 

 e.g. if a man expatiates on the distress 

 of the country, and thence argues that 

 the government is tyrannical, we must 

 suppose him to assume either 'that 

 every distressed country is under a 

 tyranny,' which is a manifest false- 

 hood, or merely that ' every country 

 under a tyranny is distressed,' which, 

 however true, proves nothing, the 

 middle term being undistributed." 

 The former would be ranked, in our 

 distribution, among Fallacies of Gene- 

 ralisation, the latter among those of 

 Ratiocination. *' Which are we to sup- 

 pose the speaker meant us to under- 

 stand? Surely" (if he understood 

 himself) " just whichever each of his 

 hearers might happen to prefer : some 

 might assent to the false premise : 

 others allow the unsound syllogism." 



Almost all fallacies, therefore, might 

 in strictness be brought under our 

 fifth class, Fallacies of Confusion. A 

 fallacy can seldom be absolutely re- 

 ferred to any of the other classes : we 

 can only say that if all the links were 



