156 THE UNIQUENESS OF LIFE 



In a case of this sort it is the opinion of expert physicists 

 that is most valued, and in discussing the analogous case 

 of the operation of our will, the late Prof. J. H. Poyn- 

 ting, an authority of eminence, suggested that a merely 

 deflecting force does no work though it changes configura- 

 tion. The will may introduce a constraint which guides 

 molecules to glide past one another instead of clashing a 

 slight change of spin which may be compensated for by a 

 slight opposite spin put on the rest of the body. " The will 

 may act as a guiding power changing the direction of the 

 atoms and molecules in the brain, and we can imagine such 

 a guiding power without having to modify our ideas of 

 the constancy of matter or the constancy of motion or even 

 the constancy of energy" (Poynting, 1903, p. 745). 



(&) A recurrent argument in Driesch's exposition of his 

 doctrine of vitalism is that no machine-like agency can possi- 

 bly account for the facts of development, inheritance, and be- 

 haviour. A machine is defined as " a given specific combina- 

 tion of specific chemical and physical agents ", and Driesch 

 seeks to reduce to absurdity the theory that any machine could 

 do what is required. His argument is very convincing, but 

 of course we can argue only about machines that we know, 

 and imaginative combinations or improvements of these, so 

 it seems open to the critic to reply that no one knows all possi- 

 ble machines, and to urge that proving the untenability of a 

 machine-theory does not prove the necessity of postulating 

 an Entelechy. 



Concerning the ingenious machines almost super- 

 machines invented by man, it may not be needless to re- 

 mind ourselves that their introduction into the argument 

 is apt to be fallacious. For they, like the wonderful achieve- 

 ments of the synthetic chemists, are the fruits of intelligence, 



