understood that the word sensation is simply a term for the something intermediate between the object and our faculty of cognition.[1] We have, therefore, simply to state why we have admitted that the external perception of objects is produced mediately or by procuration.
There are a few philosophers, and those not of the lowest rank, who have thought that this intermediate character of all perception was so evident that there was no need to insist further upon it. John Stuart Mill, who was certainly and perhaps more than anything a careful logician, commences an exposition of the idealist thesis to which he was so much attached, by carelessly saying: “It goes without saying that objects are known to us through the intermediary of our senses. . . . The senses are equivalent to our sensations;”[2] and on those propositions he rears his whole system. “It goes without saying . . .” is a trifle thoughtless. I certainly think he was wrong in not testing more carefully the solidity of his starting point.
In the first place, this limit set to our knowledge of the objects which stimulate our sensations is only accepted without difficulty by well-informed
