THE CRITERION OF MIND. 19 



In positing the evidence of Choice as my objective (or 

 ejective) criterion of Mind, I do not think it necessary to 

 enter into any elaborate analysis of what constitutes this 

 evidence. In a subsequent chapter I shall treat fully of 

 what I call the physiology or objective aspect of choice ; and 

 then it will be seen that from the gradual manner in which 

 choice, or the mind-element, arises, it is not practically 

 possible to draw a definite line of demarcation between 

 choosing and non-choosing agents. Therefore, at this stage 

 of the enquiry I prefer to rest in the ordinary acceptation of 

 the term, as implying a distinction which common sense has 

 always drawn, and probably always will draw, between mental 

 and non-mental agents. It cannot be correctly said that a 

 river chooses the course of its flow, or that the earth chooses 

 an ellipse wherein to revolve round the sun. And similarly, 

 however complex the operations may be of an agent recog- 

 nized as non-mental — such, for instance, as those of a calcu- 

 lating machine — or however impossible it may be to predict 

 the result of its actions, we never say that such operations or 

 actions are due to choice ; we reserve this term for operations 

 or actions, however simple and however easily the result may 

 be foreseen, which are performed, either by agents who in 

 virtue of the non-mechanical nature of these actions prove 

 themselves to be mental, or by agents already recognized as 

 mental — i.e., by agents who have already proved themselves 

 to be mental by performing other actions of such a non- 

 mechanical or unforeseeable nature as we feel assured can 

 only be attributed to choice. And there can be no reasonable 

 doubt that this common-sense distinction between choosing 

 and non-choosing agents is a valid one. Although it may be 

 difficult or impossible, in particular cases, to decide to which 

 of the two categories this or that being should be assigned, 

 this diiliculty does not affect the validity of the classification 

 — any more, for instance, than the difficulty of deciding 

 whether Lunulas should be classified with the crabs or with 

 the scorpions affects the validity of the classification which 

 marks off the group Crustacea from the group Arachnids* 

 The point is that, notwithstanding special difficulties in 

 assigning this or that being to one or the other class, the 

 psychological classification which I advocate resembles 

 the zoological classification which I have cited ; it is a valid 

 classification, inasmuch as it recognizes a distinction where 



