THINGS DENOTED BY NAMES. 39 



It is certain, then, that a part of our notion of a body consists of the 

 notion of a number of sensations of our own, or of otlier sentient beings, 

 habitually occurring simultaneously. My conception of the table at 

 which I am writing is compounded of its visible form and size, which 

 are complex sensations of sight ; its tangible form and size, which are 

 complex sensations of our organ of touch and of our muscles ; its 

 weight, which is also a sensation of touch and of the muscles ; its color, 

 wliich is a sensation of sight ; its hardness, which is a sensation of the 

 muscles ; its composition, which is another word for all the varieties of 

 sensation which we receive under various circumstances from the wood 

 of which it is made ; and so forth. All or most of these various sensa- 

 tions frequently are, and, as we learn by experience, always might be, 

 experienced simultaneously, or in many differefit orders of succession, 

 at our own choice : and hence, the thought of any one of them makes 

 us think bl" the others, and the whole become mentally amalgamated into 

 one mixed state of consciousness, which, in the language of the school 

 of Locke and Hai'tley, is termed a Complex Idea. 



Now there ai-e philosophers who have argued as follows: — if we 

 take an orange, and conceive it to be divested of its natural color 

 without acquiring any new one ; to lose its softness without becoming 

 hard, its roundness without becoming square or pentagonal, or of any 

 other regular or irregular figure whatever ; to be deprived of size, of 

 weight, of taste, of smell ; to lose all its mechanical and all its chemical 

 properties, and acquire no new ones ; to become, in short, invisible, 

 intangible, and imperceptil)le not only by all our senses, but by the 

 senses of all other sentient beings, real or possible ; nothing, say these 

 philosophers, would remain. For of what nature, they ask, could be 

 the residuum "? and by what token could it manifest its presence 1 To 

 the unreflecting its existence seems to rest on the evidence of the 

 senses. But to the senses nothing is apparent except the sensations. 

 We know, indeed, that these sensations are bound together by some 

 law; they do not come together at random, but according to a systematic 

 order, which is part of the order established in the universe. When 

 we experience one of these sensations, we usually experience the others 

 also, or know that we have it in our power to experience them. But 

 a fixed law of connexion, making the sensations occur together, does 

 not, say these philosophers, necessarily require what is called a sub- 

 stratum to support them. The conception of a substratum is but one 

 of many possible forms in which that connexion presents itself to our 

 imagination ; a mode of, as it were, realizing the idea. If there be 

 such a substratum, suppose it this instant annihilated by the fiat of 

 Omnipotence, and let the sensations continue to occur in the same 

 order, and how would the substratum be missed 1 By what signs 

 should we be able to discover that its existence had terminated 1 should 

 we not have a.s much reason to believe that it still existed, as we now 

 have ] and if we should not then be wananted in believing it, how 

 can we be so now? A body, therefore, according to these meta- 

 physicians, is not anything intrinsically different from the sensations 

 which the body is said to produce in us ; it is, in short, a set of sensa- 

 tions joined together according to a fixed law. 



These ingenious speculations have at no time in the history of phi- 

 losophy made many ])roselyt(!H ; but the controversies to which they 

 have given rise, and the doctrines which have been developed in the 



