110 



ORGANISM AND MECHANISM 



§ 2. Chemical and Physical Laws apply to Organisms. 



The apartness of living creatures v/as stated by Kant in 

 a famous passage. ^^ It is quite certain that we cannot be- 

 come sufficiently acquainted with organised creatures and 

 their hidden potentialities by aid of purely mechanical 

 natural principles; much less can we explain them; and 

 this is so certain, that we may boldly assert that it is absurd 

 for man even to conceive such an idea, or to hope that a 

 Newton may one day arise able to make the production 

 of a blade of grass comprehensible, according to natural 

 laws ordained by no intention; such an insight we must 

 absolutely deny to man " (Teleological Faculty of Judgment, 

 § 74). We wonder how much of this he would have 

 written had he known the bio-chemistry and bio-physics of 

 to-day. 



It is now recognised by all — vitalists included — that 

 chemical and physical laws apply to living creatures — ^to 

 what may be called their inorganic aspect. There is no 

 confusion of ' categories ' in so doing. Chemically regarded, 

 the living creature is of a piece with its surroundings ; it 

 contains no peculiar elements. The most essential sub- 

 stances, which are always present, are proteins, but there 

 is nothing rare in their composition, — just the carbon, 

 hydrogen, oxygen, nitrogen, and so on of the surrounding 

 world. The peculiarity of proteins is in the complexity 

 of their molecules, which consist of a large number of 

 atoms, and in their general occurrence in a colloid state, 

 which has very important physical properties. It used to 

 be thought that organic substances could be made only by 

 the direct touch of life, but the s^Tithctic chemist has built 

 up samples of most of the different kinds with the exception 



