THE INHERITED IMPULSE. 137 



expands itself and goes through the same series of 

 activities in each generation, — activities which are 

 familiarly classed as the phenomena of birth, growth, 

 and development. This repetition has the effect of 

 making the processes easier and more rapid, and by- 

 association they become interlocked as links in a 

 chain of events which make up the life of each 

 individual. 



Reasoning from analogy and the general principle 

 of evolution, we may suppose the first living matter 

 to have made only the simplest mechanical responses 

 to stimuli ; but as the effect of each repetition of the 

 same actions impresses itself on the living matter, 

 the latter becomes more complex with each repeti- 

 tion, and thus we can imagine how, with the increas- 

 ing complexity of living matter, there arose a corre- 

 spondingly wonderful complexity of responses to 

 stimuli. 



As the round of activities which make up the life 

 of each generation is constantly repeated by each 

 generation, it follows that the continuity of living 

 matter must become more and more complex ; that 

 is, the associations of actions — both animal and 

 vegetable processes — become more strongly bound 

 together and fixed in relation to each other. As 

 each generation, therefore, possesses a greater com- 

 plexity of structure than the previous generation, so 



