HISTORY OF EVOLUTION — PETRONIEVICS. 331 



Buffon begins by being an adherent of the idea of fixity of species ; 

 but later, he has a partial glimpse of their transmutability. The 

 great Swedish naturalist Linnaeus formulates, on the contrary, the 

 theory of the fixity of species, teaching that there are "as many 

 species as there came couples from the hands of the Creator ". 



But it was in France at the end of the eighteenth century that 

 the doctrine of inorganic evolution was elaborated for the first 

 time in a scientific manner by the mathematician and astronomer 

 Laplace; he, however, limited his doctrine to the solar system (in 

 a note to his work, " Exposition du systeme du monde," 1796). 



The French thinkers of the eighteenth century, Turgot and 

 Condorcet, also hold an important place in the development of the 

 theory of social evolution. 



The great German philosophers of the commencement and of the 

 first half of the nineteenth century were in general opponents of 

 evolutionism. Schelling's philosophy of identity supposes in nature 

 a series of gradations beginning in inorganic forces passing through 

 organic beings, and finishing in self-conscious mind. But these 

 gradations, according to him, are all in existence simultaneously. 

 Hegal admits Schelling's antievolutionistic point of view as to 

 nature (the inorganic and organic world) — nature being, according 

 to his idea, the externalization of the idea, the essence of which is 

 only a purely logical process of conceptual evolution. But in the 

 domain of mind, Hegel expressly recognizes temporal evolution, 

 and he is one of the most important proponents of the intellectual 

 and social evolution. (His work " Philosophie der Geschichte " is a 

 work which marks a date in the history of this evolution.) Schopen- 

 hauer is still more reactionary than Hegel; he declares himself a 

 resolute opponent of evolution in the domain of nature (where he 

 recognizes only degrees of objectivation of the will) as in those of 

 the mind and of history. He also admits in geology the theory of 

 revolutions. 



Among the disciples of Schelling, on the contrary, some are 

 declared sympathizers with the doctrine of organic transformation. 

 First, Oken, who advances the theory of cells by his doctrine of 

 infusorian spheres (these becoming animals in the water and plants 

 in the air) ; these spheres, according to Oken, being the immediate 

 product of the primitive jelly. Immediately afterhim came Treviranus 

 who, even before Oken and at the same time as Lamarck in France, 

 had developed the doctrine of organic transformation (in his work, 

 "Biologie oder Philosophie der lebenden Natur," 6 Bde, 1802-1822). 

 Oken and Treviranus were as distinguished naturalists as philos- 

 ophers, and they are the only philosophers who, as original thinkers, 

 clearly conceived and maintained the doctrine of organic evolution. 



