viii INTRODUCTION 



the ether of space. It must be admitted that the 

 conception appears to the layman to involve only 

 contradictions : heterogeneous, discontinuous, ponder- 

 able atoms are only singularities in a homogeneous, 

 continuous, imponderable medium, or ether. Yet it is 

 easy to see that this contradiction arises in our mind 

 only because we had previously thought of the Universe 

 in terms of matter and energy, and in spite of ourselves 

 we attempt to think of the new Reality in terms of the 

 old one. In its attempt to understand all its later 

 results Physics had therefore to invent a new Philo- 

 sophy—that of the ether of space. 



It is only in our own times that Biology has become 

 sceptical and has begun to doubt whether its earlier 

 Philosophy is a sound one. That which it describes— 

 the object-matter of its Science— is not that which 

 Physics describes. There are two domains of Given- 

 ness, the organic and the inorganic. Biology, leaning 

 on Physics, studied motions and transformations, just 

 as Physics did, though the motions which it studied 

 were more complex and the transformations more 

 mysterious. But borrowing the methods of investiga- 

 tion of Physics it borrowed also its Philosophy, and so it 

 placed behind its Givenness the Reality that Physics 

 at first postulated and then abandoned. The organism 

 was therefore a material system actuated by energy. 

 The notion, it should be noted, is not a deduction from 

 the results of Biology, but only from its methods. 



Did Physiology, that is, the Physiology of the 

 Schools, ever really investigate the organism ? A 

 muscle-nerve preparation, an excised kidney through 

 which blood is perfused, an exposed salivary gland 

 which is stimulated, even a frog deprived of its cerebral 

 hemispheres— these things are not organisms. They 

 are not permanent centres of action, autonomous 



