FACTS OF INHERITANCE 131 



tion hetween, Successive Generations. — Another step 

 is, that we are learning not to spell heredity 

 with a capital " h." We no longer think of it 

 as a power or as a principle, as a fate or as 

 one of the forces of nature ; we study it as a 

 genetic relation which is sustained by a visible 

 material basis, as a relation of resemblances and 

 differences which can be measured and weighed, or 

 in some way computed. In regard to property 

 there is a clear distinction between the heir and 

 the estate which he inherits ; but at the beginning 

 of an individual life there i& biologically no such 

 distinction. The organism and its inheritance are, 

 to begin with, one and the same. We inherit our- 

 selves. Thus " heredity " is simply a convenient term 

 for the genetic relation between successive generations, 

 and inheritance includes all that the organism is, or 

 has, to start with in virtue of its hereditary relation. 



(3) Appreciation of Distinction between " Nature " 

 and " Nurture." — Another step, following on 

 the last, is that we have begun to reahse more 

 clearly the distinction imphed in the words 

 " nature " and " nurture " — a distinction made 

 by Shakespeare and definitised by Galton. The 

 fertilised egg-cell contains, in some way which 

 we cannot picture, the potentiality of a particular 

 living creature — a tree, a daisy, a horse, a man. 

 If this inheritance is to be realised there must be 

 an appropriate environment, supplying food and 

 oxygen and necessary stimuli of many kinds. With- 

 out this nurture the inherited nature can achieve 

 nothing. The development of every character 

 implies the interaction of the two sets of factors — 

 the internal organisation and the external environ- 

 ment. But the surrounding influences are often very 



