The Scottish Naturalist. 253 



or conscious units that forms the animal kingdom ? (Goodsir 

 1, 210, 274, 282). 



What further is to be done in travailing in the difficult task 

 of explaining the animal soul is plain enough. We have to 

 observe; and we have to interpret our observations. We have 

 to go on just much as we 'have been doing. There is no other 

 method. Only, it is to be remembered that the field of observa- 

 tion is not the world of animal action alone ; nor is it that 

 world first. Unless we enter that territory furnished with 

 adequate and accurate observations of the world of human 

 intelligence and action, we shall enter it to no purpose, or only 

 to blunder. " As the facts of human psychology," says Good- 

 sir, " are attained by a process of self-examination, it is evident 

 that we can only investigate comparative psychology by an in- 

 direct method. Nevertheless, as we can compare the combined 

 instinctive and rational elements of our own human economy, 

 so we may, with confidence, conduct our indirect comparative 

 psychological investigations under the control of our own ex- 

 perience." It is the same rule that holds elsewhere, that holds 

 here. We must, if we are to philosophise beyond ourselves at 

 all, philosophise at least j6w* ourselves outward. Hence, when- 

 ever we deal with beings of the same mental nature with 

 ourselves, this rule makes the accurate philosophy of the inves- 

 tigator's own mind at the same time the accurate philosophy of 

 the minds which he is investigating. But when we come, in 

 the application of our rule, to deal with beings that present 

 mental variation from ourselves, we encounter difficulty from 

 the conditions and limitations to which the rule is then neces- 

 sarily subject. Thus is it in the case of animal psychosis. 

 Nevertheless, it is the application here of the only rule possible 

 to us anywhere, that conditions the very possibility of a com- 

 parative psychology. In the direction of this topic, Mr. Douglas 

 Spalding makes two statements that provoke animadversion. 

 He says, ■* in its fundamental principles the science of mind must 

 be the same for all living creatures." (Nature, vii. 229). The 

 answer is, undoubtedly, provided the mind of all living creatures 

 is the same. But that is the question that may be to be settled ; 

 and it will not do to beg it. Mr. Spalding then adds : "farther, if 

 man, as is now believed, be but the highest, the last, the most 

 complex product of evolution, a system, professing to be an 

 analysis and exposition of his mind, yet confessing itself incom- 

 petent to deal with the necessarily simpler mental processes of 



