INTRODUCTORY 23 



same substance—' primitive slime,' ' Urschleim ' as he called it, or, 

 as we should now say, 'protoplasm.' We can therefore, mutatis 

 mutandis, agree with Oken when he says, ' Everything organic has 

 come from ■ slime, and is nothing but diversely organized slime.' 

 Many naturalists of the present day would go further, and agree with 

 Oken when he suggests that ' this primitive slime has arisen in the 

 sea, in the course of the planet's (the earth's) evolution out of in- 

 organic material.' 



Thus Oken postulated, as the specific vehicle of life, a primitive 

 substance, in essence at least homogeneous. But he went further, 

 and maintained that his ' Urschleim ' assumed the form of vesicles. 

 of which the various organisms were composed. ' The organic world 

 has as its basis an infinitude of such vesicles.' Who is not at 

 once reminded of the now dominant Cell-theory 1 And, in fact, thirty 

 years later, when the cell was discovered, Oken did claim priority for 

 himself. In so doing, he obviously confused the formulating of 

 a problem with the solving of it ; he had, quite rightly, divined 

 that organisms must be built' up of very minute concentrations of the 

 primitive substance, but he had never seen a cell, or proved the 

 necessity for its existence, or even attempted to prove it. His vesicle- 

 theory was a pure divination, a prevision of genius, but one which 

 could not directly deepen knowledge ; it did not prompt, or even 

 hasten, the discovery of the cell. Here, as throughout in his natural 

 philosophy, Oken built, not from beneath upwards, by first establish- 

 ing facts and then drawing conclusions from them, but, inversely, he 

 invented ideas and principles, and out of them reconstructed the 

 world. In this he differs essentially from his predecessors Erasmus 

 Darwin, Treviranus, and Lamarck, who all reasoned inductively, that 

 is, from observed data. 



Thus the whole evolutionary movement was lost in indefinite- 

 ness; because men wanted to find a reason for everything, they 

 missed even what might then have been explained. Moreover, the 

 theory of evolution still lacked a sufficiently broad basis of facts: 

 the ' Naturphilosophie,' by its want of moderation, robbed it of all 

 credit ; and it is not to be wondered at that men soon ceased to occupy 

 themselves with* the problem of the evolution of the living world. 

 A few indeed held fast to the doctrine of evolution during the first 

 third of the century, but then it disappeared completely from the realm 

 of science. 



Its last flicker of life was seen in France, in 1 830, at the time 

 of the July revolution, when the legitimate sovereignty of Charles X 

 was overthrown. It is interesting to note the lively interest that 



