154 NATURE OF SENSATION. 



As regards sensations and feelings, we desire to be 

 informed by those who profess to understand them, con- 

 cerning the physical changes which necessarily occur when 

 feeling sensation, is manifested. 



If "sensation" is due to the action of a number of 

 different tissues, it must be a very complex process, and 

 ought, in that case, to be resolved into its component phe- 

 nomena, and the exact importance of each ought then to be 

 determined. But some observers seem hardly to have made 

 up their minds whether nerve is absolutely essential to sensa- 

 tion or not. They hint that a low order of sensation may 

 be manifested independently of nerve tissue of any kind. 

 Are there, in fact, two kinds of sensation? i. Nerve sen- 

 sation, and 2, Sensation in matter which is not nervous ? 

 This at any rate ought to be determined before the general 

 question is even entered upon. In this, as in many other 

 cases, much discussion is carried on without the exact ques- 

 tion, which it is desired to determine, being clearly stated or 

 accurately denned. What is feeling ? what is sensation in 

 its simplest condition ? and what is absolutely necessary to 

 its existence ? 



Mr. Herbert Spencer remarks, " that all forms of sensi- 

 bility to external stimuli are, in their nascent shapes, nothing 

 but the modifications which those stimuli produce (!) in that 

 duplex process of assimilation and oxidation which consti- 

 tutes primordial life," but we are left in utter darkness as 

 to the " modifications." " There are some propositions in 

 which." as Mr. Spencer well remarks, "what is tacitly 

 asserted immensely exceeds in amount what is avowedly 

 asserted." Mr. Spencer further explains, that when the 

 tissue of a zoophyte is touched, the fluids diffused 



