Humanity in Limited Privilege 385 



instead of nearer and baser impulses, enables the associated 

 action of larger and larger numbers of men; and so achieves 

 the great and greater effectiveness of human power, in civil- 

 ization, as compared with that power uncivilized, or as 

 against the brute powers, and the naturally hostile environ- 

 ment. This too, the activity in free and voluntary unison, 

 is a new phase, and marks an era in social organization. 



And in biology there are other instructive facts of the 

 same kind which show that the basis of all such evolution is 

 in a common law. There are long enduring types, running 

 into innumerable changes, of close relationship; which are 

 seen bursting into a comparatively sudden evolution of a 

 new type, as if by some new impulse. The appearance of 

 the vertebrata for example after long evolution of inverte- 

 brates, is seen in the geological record to have opened up 

 a new morphology. And embryology too supports this 

 evidence, with a discontinuous, or two-phase development, 

 which has even suggested its possible origin in an alternat- 

 ing species. The symmetrical and axial motive of form, 

 beginning in an old type, reaches therein a certain definition 

 (the gastrula) and yet later this disappears in a new axial 

 symmetry arising within it. It appears that a revolutionary 

 variation came into sudden preference. It seems as if that 

 impulse then rapidly achieved the main character of its 

 new creation, and as if then the creative power entered upon 

 a long series of selective and of merely adaptive variation. 

 There are now few evidences of present evolutions of origi- 

 nal features in vertebrate life forms. There is active modi- 

 fication of limbs and organs and of things which the past 

 has already established in a kind of completeness. 



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