INTRODUCTION Xlll 



Biochemistry has provided explanations in many fields of physiology 

 and we can now perceive the preliminary signs of similar progress in a 

 field that up to now has been outside the scope of biochemical explanation — 

 that of electrophysiology. The demystification of biology will be a long 

 and arduous task which is only just beginning. Much work remains to be 

 done before the natural order, natural selection, adaptation, evolutionary 

 tendencies, orthogenesis, morphogenesis, etc., are replaced by a know- 

 ledge of the reality underlying these somewhat poetic terms. 



The author is conscious of the imperfections of his book and criticisms 

 which could be levelled at it. Nevertheless, perhaps biochemists will 

 find therein reasons for interesting themselves to advantage in biochemical 

 variation and not solely in the unitarian aspects of biochemistry. Perhaps 

 chemists will find reasons for recognizing that although it is true that 

 chemistry' is one, and everywhere obeys the same laws, yet the chemist 

 within the living cell has his own special methods which can only be 

 unravelled by means of the experimental study of living material. Perhaps, 

 also, the essays that follow will assist in convincing certain biologists that 

 they are wrong when they assert that the natural realities which we des- 

 cribe by the concepts of species and taxonomic classes no longer exist at 

 the level of the molecular phenomena which is the study of biochemistry. 

 In addition, perhaps, they will also become convinced that the field of the 

 metaboHsm, of cells, of organisms, and of the biosphere itself, offers a 

 fruitful region for the study of some of the most fundamental problems of 

 biology. 



Although unable to flatter himself with unqualified success in an under- 

 taking as difficult as this, the author feels confident of the indulgence of 

 the reader for any omissions or errors he may have committed. 



Marcel Florkin 



