4(J0 THE SENSORIAL FUNCTIONS. 



that which gives the feeling of resistance produces 

 the sensation of itching, which is totally different 

 in its kind. The sensation of cold is equally posi- 

 tive with that of warmth, and differs from it, not in 

 degree merely, but in species ; although we know 

 that it is only in its degree that the external cause 

 of each of these sensations differs. 



The only distinct notions we are capable of form- 

 ing respecting Matter, are, that it consists of certain 

 powers of attraction and repulsion, occupying cer- 

 tain portions of space, and capable of moving in 

 space ; and that its parts thereby assume different 

 relative positions or configurations. But of mind, 

 our knowledge is more extensive and more precise ; 

 because we are conscious of its existence, and of 

 many of its operations, which are comprised in the 

 general term thought. To assert that thought can 

 be a property of matter, is to extend the meaning 

 of the term matter to that with which we cannot 

 perceive it has any relation. All that we know 

 of matter has regard to space : nothing that we 

 know of the properties and affections of mind has 

 any relation whatsoever to space. 



A similar incongruity is contained in the pro- 

 position that thought is aj'unctio/i of the brain. It 

 is not the brain which thinks, any more than it is 

 the eye which sees ; though each of these material 

 organs is necessary for the production of their 

 respective effects. That which sees and which 

 thinks is exclusively the mind ; although it is by 

 the instrumentality of its bodily organs that these 

 changes take place. Attention to this fundamental 

 distinction, which, although obvious when explicitly 

 pointed out, is often lost sight of in ordinary dis- 



