450 METAPHYSICAL EVOLUTION. 



The field of the known is very limited, as compared with that 

 of the unknown, in the experience of the Amceba. In its first 

 movements, it has absolutely no basis on which to establish an 

 anticipation of the future. Such is also the situation of the young 

 of every animal. But the cases of the inferior and superior spe- 

 cies present the important difference that in the former there 

 exist few or no mental powers derived by inheritance, while in 

 the latter such are present in proportion to the position of the 

 species in the scale of intelligence. 



The facts of evolution teach that the habits of animals have 

 been modified during past geological ages, under the influence of 

 changes in their physical surroundings. While these changes may, 

 perhaps, have furnished the stimuli to the adoption of new habits, 

 the conditions have not often been so rigid as to define exactly 

 what those habits should be, in some or all of their details. The 

 animal has necessarily proceeded blindly in many instances ; in 

 others, his mental darkness has been illumined by a low grade of 

 imagination. This may be believed in view of the many attempts 

 which animals often make before succeeding in attaining a desired 

 end. Imagination plays an important part in the origin of mo- 

 tives and of actions, and is related to predication. It is defined 

 as the presentation or construction of images or representations 

 from items of experience, which representations so far differ in 

 the connection of their details from actual experience, or so far 

 lack the qualities of experiences, as not to constitute a predica- 

 tion of future events. Predication may be defined as the certain 

 knowledge of the unexperienced from the experienced ; while 

 imagination includes the grades of probable, possible, and impos- 

 sible concepts, constructed from the same material as predication. 

 Whether this faculty exists in the animals which can not speak, 

 is not readily ascertained ; but, inasmuch as many of them predi- 

 cate, it is probable that they possess some degree of imagination 

 also. But it is obviously a quality of the highest types of mind, 

 since its development depends primarily on the furniture of mem- 

 ory, derived from a long period of experience, whose amount de- 

 pends on receptivity and retentiveness. 



VI. THE OKIGIJSr OF MOTIVES. 



It has been said that the operation ordinarily called choosing, 

 in which the will is popularly supposed to be free, consists merely 

 of a sum in addition and subtraction, where various inducements 



