54 MENTAL EVOLUTION IN ANIMALS. 



review of the evidence on this point, I may here meet a 

 difficulty which has already arisen. The difficulty is that I 

 began by showing it necessary to define Mind as the power 

 of exercising Choice, and then proceeded to define the latter 

 as a power belonging only to agents that are able to feel. 

 Yet, on looking at the objective side of the problem, I 

 pointed out that the physiological or objective equivalent of 

 Choice is found to occur in its simplest manifestations at 

 least as low down as the insectivorous plants, which are 

 certainly not agents capable, in any proper sense of the term, 

 of feeling. Therefore it seems that my conception of what 

 constitutes Choice is in antagonism with my view that the 

 essential element of Choice is found to occur among organ- 

 isms which cannot properly be supposed to feel. And this 

 antagonism, or inherent contradiction, is a real one, though I 

 hold it to be unavoidable. For it arises from the fact that 

 neither Feeling nor Choice appears upon the scene of life 

 suddenly. We cannot say, within extensive limits, where 

 either can properly be said to begin. They both dawn 

 gradually, and therefore in our everyday use of these terms 

 we do not wait to consider where they are first applicable; 

 we only apply them where we see their applicability to be 

 apparent. But when we endeavour to use these same terms 

 in strict psychological analysis, we are at once met with the 

 difficulty of drawing the line where the terms are applicable 

 and where they are not. There are two ways of meeting the 

 difficulty. One is to draw an arbitrary line, and the other is 

 not to draw any line at all; but to carry the terms down 

 through the whole gradation of the things until we arrive at 

 the terminal or root-principles. By the time that we do arrive 

 at these root-principles, it is no doubt true that our terms have 

 lost all their original meaning ; so that we might as well call 

 an acorn an oak, or an egg a chicken, as speak of a Dioncea 

 feeling a fly, or of a Drosera choosing to close upon its prey. 

 Yet this use ; or rather let us call it abuse, of terms serves one 

 important purpose if, while duly regarding the change of 

 meaning which during their gradual descent the terms are 

 made gradually to undergo, we thus serve to emphasize the 

 fact that they refer to things which are the product of a 

 gradual evolution — things which came from other tilings as 

 unlike to them as oaks to acorns or chickens to eggs. And 

 this is my justification for tracing back the root-principles of 



