OBSERVATION AND DESCRIl'TION. 385 



But it is not my toucli in this case, nor my sight in tlie other, whicli is 

 deceived ; the deception, whether durable or only momentary, is in 

 my judgment. From my senses I have only the sensations, and those 

 are genuine. Being accustomed to have those or similar sensations 

 when, and only when, a certain arrangement of outward objects is 

 present to my organs, I have the habit of instantly, when I experience 

 the sensations, inferring the existence of that state of outward things. 

 This habit has become so powerful, that the inference, performed with 

 the speed and certainty of an instinct, is confounded with intuitive 

 perceptions. When it is correct, I am unconscious that it ever needed 

 proof; even when I know it to be incorrect, I camiot without consid- 

 erable effort abstain from making it. In order to be aware that it is 

 not made by instinct but by an acquired habit, I am obliged to reflect 

 on the slow process by which I learned to judge by the, eyfe of many 

 things which I now appear to perceive directly by sight ; and on the 

 reverse operation performed by persons learning to draw, who with 

 difficulty and labor divest themselves of their acquired perceptions, 

 and learn afresh to see things as they appear to the eye, instead of see- 

 ing them as they really arc. 



It would be easy to prolong these illustrations, were there any need 

 to expatiate upon a topic so copiously exemplified in various popular 

 works. From the examples already given, it is seen sufficiently, that 

 the individual facts from which we collect our inductive generalizations 

 are scarcely ever obtained by observation alone. Observation extends 

 only to the sensations by which we recognize objects; but the propo- 

 sitions which we make use of, either in science or in common life, 

 relate mostly to the objects themselves. In every act of what is called 

 observation, there is at least one inference, from the sensations to the 

 presence of the object ; from the marks or diagnostics to the entire 

 phenomenon. And hence, among other consequences, follows the 

 seeming paradox, that a general proposition collected from particulars 

 is often more certainly true than any one of the particular propositions 

 from which, by an act of induction, it was infeiTed. For, each of those 

 particular (or rather singular) propositions involved an inference, from 

 the impression on the senses to the fact which caused that impression : 

 and this inference may have been erroneous in any one of the instances^ 

 but cannot well have been erroneous in all of them, provided their 

 number was sufficient to eliminate chance. The conclusion, therefore, 

 that is, the general proposition, may deserve more complete reliance 

 than it would be safe to repose in any one of the inductive premisses. 



The logic of observation, then, consists solely in a correct discrimi- 

 nation between that, in a result of obsei-vation, which has really been 

 perceived, and that which is an inference; from the perception. What- 

 ever portion is inference, is amenable to the rules of induction already 

 treated of, and requires no further notice here : the question for us in 

 this place is, when all which is inference is taken away, what remains'? 

 There remain, in the first place, the mind's own feelings or states of 

 consciousness, namely, its outward feelings or sensations, and its inward 

 feelings — its thoughts, emotions, and volitions. Whether anything else 

 remains, or all else is inference from this ; whether the mind is capable 

 of directly perceiving or apprehending anything except states of its 

 own consciousness — is the peculiar problem of the higher or trans- 

 cendental metaphysics. But after excluding all questions on which 

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