158 OF MIND. 



opinion upon the nature of a mental process we must at 

 least be able to form a conception of the actions which 

 immediately precede the observed changes of form in a 

 mass of very simple living matter that can be easily subjected 

 to investigation, and of the antecedent change which determines 

 these actions. But unfortunately at present we have no means 

 of investigating this most important question. We cannot 

 explain why one part of a living mass should move in ad- 

 vance of another. To say the movement must be the con- 

 sequence of some antecedent phenomenon will only satisfy 

 those who are content to receive arbitrary assertions in 

 place of explanations. The supposed antecedent phe- 

 nomenon is unknown, and is, perhaps, in the present state of 

 things, unknowable. It is probably altogether wrong to use 

 the word phenomenon here at all, the antecedent in this case 

 not being a phenomenon. Until the movements of the living 

 matter of an amoeba or a white blood-corpuscle have been 

 satisfactorily accounted for, it is not likely we shall be able 

 to arrive at any positive conclusions concerning the nature 

 of the actual changes in the living matter which determine 

 mental nervous actions, but it is surely a step in advance if 

 it is rendered probable that these are intimately related to 

 the vital changes in germinal or living matter. The argu- 

 ments I have advanced in favour of the view that the highest 

 mental actions are associated with vital movements, and 

 are, in fact vital actions occurring in living matter, appear 

 to me to be justified by the facts I have adduced ; and 

 although there seems to be at present no possibility of 

 actual proof, I venture to think that the evidence upon 

 which my view rests, indirect though it be, will not be 

 regarded as inconclusive. 



