of protoplasm and the biological evolution of living 

 organisms. These we know soon divided into plant 

 life and animal life; and, when the brain was suffi- 

 ciently developed, animals showed the commence- 

 ment of a psychological evolution of mind. At first 

 this latest development of evolution was entirely 

 intellectual, and was chiefly employed in the preser- 

 vation of the race. At a later stage a higher develop- 

 ment took place and a moral evolution commenced. 

 Physical evolution, biological evolution, and psycho- 

 logical evolution are still going on. So far as the 

 earth is concerned, physical evolution has reached, 

 probably it has passed, its optimum; for the earth 

 cannot in the future be better fitted for the develop- 

 ment of life than it is now. Biological evolution has 

 also reached its optimum in man, whose body has 

 been practically stationary since the middle of the 

 pleistocene period, and cannot now be affected by 

 natural selection. Indeed, ever since the beginning 

 of the neolithic age, man has been engaged in com- 

 bating natural selection by endeavouring to alter the 

 surrounding conditions to suit himself. This he does 

 by making artificial warmth, building houses, 

 making clothes, and cultivating land. 



Psychological evolution, however, has not yet 

 reached its optimum. The development of the 

 human mind is but in its infancy. Man's origin 

 dates back only some tens of thousands of years, 

 while he has several millions of years before him. 

 During that time it is impossible to predict what will 

 happen ; but, so long as the external conditions are 

 favourable for the working of the brain , we may feel 



