OBSERVATION AND DESCRIPTION. 



m 



one. But it is not my touch in this 

 case, nor my sight in the other, which 

 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 infer- 

 ence, 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 cannot, without 

 considerable 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 through 

 which I learnt to judge by the eye 

 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 labour divest them- 

 selves of their acquired perceptions, 

 and learn afresh to see things as they 

 appear to the eye. 



It would be easy to prolong these 

 illustrations, were there any need to 

 expatiate on a topic so copiously ex- 

 emplified in various popular works. 

 From the examples already given, it 

 is seen sufficiently that the individual 

 facts from which we collect our in- 

 ductive generalisations are scarcely 

 ever obtained by observation alone. 

 Observation extends only to the sen- 

 sations by which we recognise objects; 

 but the propositions which we make 

 use of, either in science or in common 

 life, relate mostly to the objects them- 

 selves. 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 en- 



tire phenomenon. And hence, among 

 other consequences, follows the seem- 

 ing paradox that a general proposi- 

 tion collected from particulars is often 

 more certainly true than any one of 

 the particular propositions from which, 

 by an act of induction, it was inferred. 

 For each of those particular (or rather 

 singular) propositions involved an in- 

 ference 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 elimi- 

 nate chance. The conclusion, there- 

 fore, that is, the general proposition, 

 may deserve more complete reliance 

 than it would be safe to repose in any 

 one of the inductive premises. 



The logic of observation, then, con- 

 sists solely in a correct discrimination 

 between that, in a result of observa- 

 tion, which has really been perceived, 

 and that which is an inference from 

 the perception. Whatever portion is 

 inference, is amenable to the rules of 

 induction already treated of, and re- 

 quires no further notice here : th© 

 question for us in this place is, when 

 all which is inference is taken away, 

 what remains. There remains, 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 perceiv- 

 ing or apprehending anything except 

 states of its own consciousness — is a 

 problem of metaphysics not to be dis- 

 cussed in this place. But after ex- 

 cluding all questions on which meta- 

 physicians differ, it remains true, that 

 for most purposes the discrimination 

 we are called upon practically to ex- 

 ercise is that between sensations or 

 other feelings, of our own or of other 

 people, and inferences drawn from 

 them. And on the theory of Observa- 

 tion this is all which seems necessary 



