386 OPERATIONS SUBSIDIARY TO INDUCTION. 



metaphysicians differ, it remains true that for most purposes the dis- 

 crimination we are called upon practically to exercise is between 

 sensations or other feelings, of our own or of other people, and infer- 

 ences drauTi from them. And on the theory of Obsers'ation this is all 

 which seems necessary to be said in this place. 



§ 3. If, in the simplest observation, or in what passes for such, there 

 is a laro-e part which is not observation but something else ; so in the 

 simplest description of an observation, there is, and must always be, 

 much more asserted than is contained in the perception itself We 

 cannot describe a fact without implying more than the fact. The per- 

 ception is only of one individual thing ; but to describe it is to affirm 

 a connexion between it and every other thing which is either denoted 

 or connoted by any of the terms used. To begin with an example, 

 than which none can be conceived, more elementary : I have a sensa- 

 tion of sight, and. I endeavor to describe it by saying that I see some- 

 thing white. In saying this, I do not solely affinn my sensation ; I 

 also class it. I asseit a resemblance between the thing I see, and all 

 things which I and others are accustomed to call wliite. I assert that 

 it resembles them in the circumstance in which they all resemble one 

 another, in that which is the ground of their being called by the name. 

 This is not merely one way of describing an observation, but the only 

 way. If I would either register my observation for my own future 

 use, or make it known for the benefit of others, I must assert a resem- 

 blance between the fact which I have observed and something else. 

 It is inherent in a description, to be the statement of a resemblance, 

 or reseinblances. 



These resemblances are not always apprehended directly; by merely 

 comparing the object obseived with some other present object, or with 

 our recollection of an object which is absent. They are often ascer- 

 tained through immediate marks, that is, deductively. In describing 

 some new kind of animal, suppose me to say that it measures ten feet in 

 length, from the forehead to the extremity of the tail. I did not ascer- 

 tain this by the unassisted eye. I had a two-foot rule which I applied 

 to the object, and, as we commonly say, measured it; an operation 

 which was not wholly manual, but partly also mathematical, involring 

 the two propositions. Five times two is ten, and Things which are 

 equal to the same thing are equal to one another. Hence, the fact 

 that the animal is ten feet long is not an immediate perception, but a 

 conclusion from reasoning ; the minor premisses alone being furnished 

 by observation of the object. But this does not hinder it from being 

 rightly called a description of the animal. 



To pass at once from a very simple to a very complex example : I 

 affirm that the earth is globular. The assertion is not grounded upon 

 direct perception ; for the figure of the earth cannot, by us, be directly 

 perceived, although the assertion would not be true unless circum- 

 stances could be supposed under which its truth could be so perceived. 

 That the forni of the earth is globular, is infeiTed from certain marks, 

 as for instance from this, that its shadow throwai upon the moon is cir- 

 cular ; or this, that on the sea, or any extensive plain, our horizon is 

 always a circle ; either of which marks is incompatible with any other 

 than a globular form. I assert further, that the earth is that particular 

 kind of globe wliich is termed an oblate spheroid ; because it is found 



