THINGS DENOTED BY NAMES. 43 



we say that snow has the quality whiteness, what do we really assert ] 

 Simply, that when snow is present to our organs, we have a particular 

 sensation, which we ai'e accustomed to call the sensation of white. But 

 how do I know that snow is present ? Obviously by the sensations 

 which I derive from it, and not otherwise. I hifer that the object is 

 present, because it gives me a certain assemblage or series of sensa- 

 tions. And when I ascribe to it the attribute whiteness, my meaning 

 is only, that, of the sensations composing this group or series, that 

 which I call the sensation of white color is one. 



This is one view which may be taken of the subject. But there is 

 also another, and a different view. It may be said, that it is true we 

 knaio nothing of sensible objects, except the sensations they excite in 

 us ; that the fact of our receiving from snow the particular sensation 

 which is called the sensation of white, is the ground on which we as- 

 cribe to that substance the quality whiteness ; the sole proof of its pos- 

 sessing that quality. But because one thing may be the sole evidence 

 of the existence of another thing, it does not follow that the two are 

 one and the same. The attribute whiteness (it may be said) is not 

 the fact of our receiving the sensation, but something in the object it- 

 self; a ^.'O^i.Tr inherent in it; something ?"« virtue of which the object 

 produces the sensation. And when we affirm that snow possesses the 

 attribute whiteness, we do not merely assert that the presence of snow 

 produces in us that sensation, buf that it does so through, and by rea- 

 son of, that power or quality. 



For the puiposes of logic it is not of material importance which of 

 these views we adopt. The full discussion of the subject behmgs to 

 the department of inquiry so often alluded to under the name of the 

 higher metaphysics ; but it may be said here, that for the doctrine of 

 the existence of a peculiar species of entities called qualities, I can see 

 no foundation except in a tendency of the human mind which is the 

 cause of many delusions. I mean, the disposition, wherever we meet 

 with two names which are not precisely synonymous, to suppose that 

 they must be the names of two different things ; whereas in reality 

 they may be names of the same thing viewed in two different lights, 

 which is as much as to say under different suppositions as to surround- 

 ing circumstances. Because quality and sensation cannot be put in- 

 discriminately one for the other, it is supposed that they cannot both 

 signify the same thing, namely, the im])ression or feeling wth which 

 we are affected through our senses by the presence of an object : al- 

 though there is at least no absurdity in supposing that this identical 

 impression or feeling may be called a sensation when considered 

 merely in itself, and a quality when regarded as emanating from any 

 one of the numerous objects, the presence of which to our organs ex- 

 cites in our minds that among various other sensations or feelings. 

 And if this be admissible as a supposition, it rests with those who con- 

 tend for an entity y;^/- sc called a quality, to show that their opinion is 

 preferable, or is anything in fact but a lingering remnant of the scho- 

 lastic doctrine of occult causes ; the very absurdity which Moliere so 

 happily ridiculed when he made one of his pedantic physicians account 

 for the fact that " I'opium endormit," by the maxim " parcequ'il a une 

 vertu soporifique." 



It is evident that when the physician stated that opium had " une 

 vertu soporifique," he did not account for, but merely asserted over 



