The Organisation of Matter 



between animals and plants; but we still look 

 on life as a thing apart, a mystery impene- 

 trable to science. But the mystery is being 

 dissipated by investigation. The naturalist 

 searching for a definition of life sees before 

 him forms of increasing simplicity, and finds 

 that the very essence of life vanishes whenever 

 he endeavours to determine it with precision. 

 The physicist is reaching the same conclusion 

 in the opposite way. 



He starts from the notion, inferred from 

 superficial observation, of a matter really inert 

 and dead; but closer study soon shows him 

 the prodigious activity hidden under this 

 apparent inertia. He sees forces at work 

 diffusion, osmosis, cohesion, crystalline, cata- 

 lytic and electric actions organising matter, 

 creating forms and endowing brute substance 

 with many of the characters of living beings. 

 He also realises his incapacity to delimit his 

 domain and to say where the mineral kingdom 

 ends and where life begins. But without 

 abandoning the most prudent circumspection 

 he will at least be able to assert that many 

 phenomena hitherto considered characteristic 



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