INTROD UCTION vii 



where and may affect the grids of thermionic valves, but it has 

 never been suspected that they may affect the much more dehcate 

 systems of nervous synapses. Cosmic radiation has easily been 

 detected by gold-leaf electroscopes but, so far as we know, it 

 has no significance for the organism. And so on. It has been 

 suggested that life is a kind of affection of the (physically) dead, 

 or dying, ashes of the substance of w^hich stars are made ! It 

 is, of course, certain that this w^ant of relevance, for biology, 

 of the newer physical knowledge is only apparent and that the 

 next revolutionary advance to be made by our science will be 

 the application of these very strange physical results. 



Even now, however, it is possible to apply to the study of 

 biology the methods of thermodynamics and statistical mechanics. 

 It is comforting to notice how% in the general confusion into 

 which classical, theoretical physics has fallen, the classical con- 

 cept of entropy has remained and has even been amplified. I 

 have tried to suggest, in the following pages, what may be the 

 importance of this conception even in the speculative biology 

 of to-day. 



J- J. 



