DISCUSSION 129 



This is explicable on the ground of the unity 

 of the human soul, whose higher intellectual 

 faculties develop by aid of the lower sensual 

 powers. No instance, however, has occurred of 

 a young ape's ever becoming a reasoning old 

 ape, for in this case the psychical principle is 

 incapable of those higher mental functions 

 which alone are properly described as intel- 

 lectual activity. 



Professor Dahl next expressed a wish to say a 

 few words on the origin of the first organisms. ' It 

 is true that we are still unable to form any idea of 

 the origin of these first organisms, and this is pro- 

 bably due to our proceeding from a wrong starting- 

 point. We see highly developed organisms, and we 

 assume that the Protozoa, which seem to us low in 

 the scale of development, must have been the 

 primary forms. But our present protozoa, with 

 their extremely complex protoplasm, are highly 

 developed organisms, like man and the mammalia. 

 If we accept the theory of spontaneous generation 

 and Professor Dahl thinks we are forced to do so 

 ' we are driven to it by scientific considerations ' 

 we must imagine these first organisms as utterly 

 simple. This is not a question of possibility, but 

 it is very probable, for, as has been already pointed 

 out (by Plate), these same elements which compose 



1 Dahl must have intended to say, ' by considerations of natural philo- 

 sophy,' for the results of biological research all tend to disproye the hypo- 

 thesis of spontaneous generation. 



I 



