Exfoliation 



bably also his environment in obedience to it. 

 Two such general sets of causes, I say, could be 

 roughly distinguished from each other ; and 

 probably indeed are recognised less or more dis- 

 tinctly by everyone as acting to modify his life. 

 Nor can the life of a man at any time be said to 

 be ruled by one of these forces alone. No man 

 is modified by external conditions alone, with- 

 out any play or reaction of inner needs and desires 

 and growth from within ; nor is any man trans- 

 formed in obedience to an inner expansion without 

 sundry lets and hindrances from without. The 

 two forces are in constant play upon one another ; 

 but in some ways that would appear to be the 

 more important which proceeds from the Man 

 (or creature) himself, since this is obviously vital 

 and organic to him, and therefore the most con- 

 sistent and reliable factor in his modification, 

 while the external force arising from various 

 and remote causes must rather be regarded 

 as discontinuous and accidental. 



I propose, therefore, in these few pages to 

 consider especially this inner force producing 

 modification in man and animals to try and 

 find out of what nature it is, what is the law, and 

 what are the limits of its action premising always, 

 as already suggested, that this distinction between 

 " inner " and " outer," which is convenient and 

 easy to handle on certain planes of thought, may 

 ultimately, and in the last resort, prove very 

 difficult or even impossible to maintain. 



It is often said by Biologists that function precedes 

 185 



