I 



10 GENESIS OF MAN. 



To further explain this paradox he assumes two independent 

 forces or impulses, working harmoniously together in nature, an 

 internal formative impulse {inncrcr Bildiingstricb), and an external 

 formative impulse (ansscrcr Bildungstricb). The former of these he 

 also, in different passages, designates as the specific force [Specifica- 

 tionstrieb) and as the centripetal force ; the latter, on the other hand, 

 he calls the modifying force or impulse of variation ( Variationstricb, 

 and the centrifugal force. He also uses the term metamorphosis 

 in a general (phylogenetic) sense as applied to the changes that 

 take place in species and genera rather than in individuals. The 

 following passage contains the kernel of this entire portion of his 

 philosophy : " The idea of metamorphosis is like that of the vis 

 centrifuga, and would lose itself in infinity Avere there not a check 

 offered to it ; this check is the specific force {Spccificationstricb), the 

 stubborn power of permanency {z'dhc Behwrlichkcitsverm'vgcn) of 

 whatever has once become a reality, a vis centripeta, which in its 

 deepest foundations can possess no externality." 



If, now, we translate Goethe's internal formative impulse, specific 

 force, or centripetal force, by the modern term licredity, aswe un- 

 doubtedly may, and his external formative impulse, modifying force, 

 or centrifugal force, by the modern term adaptation, as we may 

 still more clearly do, we shall have, in Goethe's philosophy of life, 

 neither more nor less than the essential ^lements of the modern 

 doctrine of descent. 



Of course, nothing is here found but the general principles ; the 

 mode and the examples could not have been furnished in Germany 

 when Goethe wrote. 



Haeckel, however, is abundantly justified in pointing to Ger- 

 many's greatest genius as having long ago given utterance to the 

 most radical of his own doctrines and that for which he has re- 

 ceived the severest animadversions, when, in the passage first 

 quoted, he places man at the head of the mammalian class. And 

 yet, who had thought of assailing Goethe with the charge of deriv- 

 ing man from the apes ! 



With almost equal justice does Haeckel claim that, in the follow- 

 ing and other passages, Goethe has not only declared the genea- 

 logical relationship of the vegetable to the animal kingdom, but 

 has furnished the nucleus of the unitary or monophyletic theory of 

 descent. " When we consider plants and animals in their most im- 



