324 ADAPTIVENESS AND PURPOSIVENESS 



the tenth day after hatching, it shows no peculiarity. Here, 

 then, we have a simple instance of the way in which de- 

 velopment proceeds as if it were working with a purpose. 

 How comes that musculus complexus to be temporarily ex- 

 aggerated in strength, in relation to the breaking of the egg- 

 shell, an action which only occurs once in each generation ? 



The idea of adaptation is sometimes held far too nar- 

 rowly, and a needless difficulty is made over the fact that 

 some specific characters are not known to be adaptive to any 

 particular condition of life. But, in the first place, some 

 characters supposed at first to be quite indifferent have 

 been shown, after closer acquaintance with the creature, to 

 be finely adaptive. And, in the second place, an organism 

 is not a system of pegs on which a hundred ' characters ' 

 are hung, it is a harmonious unity, viable and persisting 

 in virtue of its subtle internal equilibrium as well as in 

 virtue of the adjustment of its tout ensemble to the condi- 

 tions of life. Adaptation may have an internal as well as 

 an external reference. 



Beyond particular instances of organismal adaptation, we 

 have the broad fact that in a given association of organisms 

 a balanced modus vivendi is arrived at, a compromise be- 

 tween competing interests, so that the system persists and 

 works smoothly. The balance of nature is the largest of 

 all adaptations. Just as the Systema Naturae of the tax- 

 onomist the orderly classification of the classifier speaks 

 of rationality; so the vital systema naturae which the nat- 

 uralist discloses is also a cosmos. There is a system atisation 

 or co-ordination of lives, world-wide in its scope, and becom- 

 ing ever more subtle in its accomplishment. 



