THE ORGANIC AND THE INORGANIC 299 



other time. In its " primitive " condition all was 

 given. 



Mechanistic biology does not, of course, hesitate to 

 accept this view of the evolutionary process. The 

 " Laplacian mind " must have been able to calculate 

 what would be the condition of the system at any 

 phase, knowing the positions of all the atoms or mole- 

 cules in the original nebula, and the velocities and 

 directions of motions of all these atoms or molecules. 

 Just as (in Huxley's illustration) a physicist is able to 

 calculate v/hat will be the fate of a man's breath on a 

 frosty day, so the Laplacian mind must have been able 

 to predict the fauna and flora of the world in the year 

 1913 from a complete knowledge of the material nature 

 and energetic properties of the nebula from which it 

 arose. 



We cannot fail to see, on reflection, to what this 

 view of the nature of the evolutionary process leads us. 

 The primitive world-nebula was a system of parts 

 which had extension in space. Materially it consisted 

 of atoms isolated from each other by space, and energeti- 

 cally it consisted of the movements of these atoms, and 

 of the energy of their positions with regard to each 

 other. No two atoms could occupy the same space — 

 they mutually excluded each other : this is what we 

 mean by saying that the original — and every other — 

 state of the system was a state of material things or 

 elements spatially extended. Therefore, if the physical 

 analogy is consistently to be retained, the organic 

 system undergoing evolution was a system of elements 

 which at any moment whatever were spatially extended. 

 It was really a system of atoms or molecules possessing 

 kinetic energy of motion, or potential energy of position 

 — molecules which lay outside each other, and energies 

 which were really the movements or positions of these 



