520 FALLACIES. 



CHAPTER III. 



FALLACIES OF SIMPLE INSPECTION; OR A PRIORI FALLACIES. 



§ 1. The tribe of errors of which we are to treat in the first instance, 

 are those in which no actual inference takes place at all ; the proposition 

 (it can not in such cases be called a conclusion) being embraced, not as 

 proved, but as requiring no proof ; as a self-evident truth ; or else as hav- 

 ing such intrinsic verisimilitude, that external evidence not in itself amount- 

 ing to proof, is sufiicient in aid of the antecedent presumption. 



An attempt to treat this subject comprehensively would be a trans- 

 gression of the bounds prescribed to this work, since it would necessitate 

 the inquiry which, more than any other, is the grand question of what is 

 called metaphysics, viz.. What are the propositions which may reasonably 

 be received without proof? That there must be some such propositions 

 all are agreed, since there can not be an infinite series of proof, a chain sus- 

 pended from nothing. But to determine what these propositions are, is 

 the opus magnum of the more recondite mental philosophy. Two prin- 

 cipal divisions of opinion on the subject have divided the schools of phi- 

 losophy from its first dawn. The one recognizes no ultimate premises but 

 the facts of our subjective consciousness ; our sensations, emotions, intellect- 

 ual states of mind, and volitions. These, and whatever by strict rules of 

 induction can be derived from these, it is possible, according to this theory, 

 for us to know ; of all else we must remain in ignorance. The opposite 

 school hold that there are other existences, suggested indeed to our minds 

 by these subjective phenomena, but not inferable from them, by any proc- 

 ess either of. deduction or of induction ; which, however, we must, by the 

 constitution of our mental nature, recognize as realities; and realities, too, 

 of a higher order than the phenomena of our consciousness, being the ef- 

 ficient causes and necessary substrata of all Phenomena. Among these 

 entities they reckon Substances, whether matter or spirit ; from the dust 

 under our feet to the soul, and from that to Deity. All these, according to 

 them, are preternatural or supernatural beings, having no likeness in expe- 

 rience, though experience is entirely a manifestation of their agency. Their 

 existence, together with more or less of the laws to which they conform in 

 their operations, are, on this theory, apprehended and recognized as real by 

 the mind itself intuitively ; experience (whether in the form of sensation 

 or of mental feeling) having no other part in the matter than as affording 

 facts which are consistent with these necessary postulates of reason, and 

 which are explained and accounted for by them. 



As it is foreign to the purpose of the present treatise to decide between 

 these conflicting theories, we are precluded from inquiring into the exist- 

 ence, or defining the extent and limits, of knowledge a priori, and from 

 characterizing the kind of correct assumption which the fallacy of incorrect 

 assumption, now under consideration, simulates. Yet since it is allowed 

 on both sides that such assumptions are often made improperly, we may 

 find it practicable, without entering into the ultimate metaphysical grounds 

 of the discussion, to state some speculative propositions, and suggest some 



