242 Science Religion and Reality 



complex systems to which the neo-vitahsts draw our attention are 

 capable of simplification. It is not hecessary to know the name of 

 every village in India to understand the shape of its coast-line and 

 the disposition of its cities. A good example from my own work 

 of a key-fact the discovery of which explains many other facts is 

 seen in the phosphorus metabolism of the developing bird's-egg. 

 Inorganic phosphorus is produced from organic phosphorus as it 

 develops : hence calcium is required to form the bones from the 

 shell, hence the shell becomes more brittle : hence carbon dioxide 

 which is produced in greater amount relatively the older the chick 

 can escape more easily, and so on. 



By a strange coincidence while preparing this paper such a key- 

 position has become important. E. S. Russell in his book called 

 " The Study of Living Things " supports Haldane's position and 

 makes a great deal of the impossibility of explaining bone-formation 

 on mechanistic lines. Yet the Biochemical Journal for 1924 con- 

 tains an account of Robison's discovery of an enzyme in calcifying 

 bone which transmutes phosphorus in combination with sugar into 

 phosphorus in combination with calcium for bone. The future 

 will see first of all the conditions of the enzyme's working thoroughly 

 understood, next the isolation of the enzyme in a pure state, next 

 its synthesis, and finally its assistance in contributing to a complete 

 mechanistic account of the process of bone-formation. 



But the inconceivability argument can very easily be turned 

 ?igainst its authors. It is all very well to say that mechanical 

 explanations are inconceivable, but what if someone found the con- 

 ception of the entelechy quite unintelligible ? As a matter of fact 

 most biochemists do. A directive force, which is neither matter nor 

 spirit, which can act but at the same time cannot think, and which 

 regulates chemical processes perfectly capable of regulating them- 

 selves, seems thoroughly inconceivable to the biochemist. "An 

 * Entelechy,' " as Hoernle says, " is too hypothetical a creature 

 to command conviction. It is too obviously a stopgap invented 

 ad hoc" 



The biochemist, moreover, is specially shy of it because his 

 methods, applied with such enormous success since the time of 

 Lavoisier, do not find any traces of the entelechy in practice. The 

 fact that Haldane's speculations are built up upon experiments on 

 oxygen-want is not really to the point, because other physiologists 

 are unable to secure comparable results. It is largely a question 



