PREFACE 



Of these large and crowded volumes a brief sketch indicating main 

 endeavours may be of service to the reader at the beginning, and 

 perhaps also at the close; hence a Preface, larger than is customary, 

 may be pardoned. 



The aims of this book are broadly fourfold. 



(a) We give in eight chapters our outline-survey of Biology, in 

 all its essential inquiries into the nature, continuance, and evolution 

 of living beings. 



(b) We illustrate with more care, and in more detail, than usual, 

 the relations between Biology and the other Sciences — as to 

 Chemistry and Physics on the one hand, to Psychology and 

 Sociology on the other. We have also sought to show how the 

 study of Life, as central among the sciences, and with clear 

 orientation of the sub-sciences of Biology, aids — we even think 

 illumines — the old yet ever-renewing problem of the arrangement of 

 knowledge into an adequate classification of the sciences in general, 

 and this even within their essential fields, their own sub- sciences. 



(c) Our specific presentment of Biology hence seeks to do justice 

 between "mechanistic" and "vitalistic" doctrines, since we utilise 

 the mechanistic advances, and even formulations, of bio-chemistry 

 and bio-physics for all they are worth, and that is much; yet also 

 show the need of complementing these, by no less due utilisation 

 of psychologic and neo-vitalistic viewpoints and doctrines; and 

 this especially when these are re-stated more concretely, as here 

 in outline we do. For we avoid taking refuge, as older vitalists have 

 done, and some of our contemporaries still do, in metaphysical 

 transcendentalisms, not definitely enough related to the actual 

 processes of Life, in Evolution, and to Life-histories as we naturalists 

 observe them. Central to our thinking are Life's fundamental 

 categories; of Organism, Function, and Environment; and these 

 not merely as separately investigated, but in their varied harmonies, 

 throughout that perpetual interaction which is the essential of Life at 

 all its levels of being and becoming. Hence throughout this book there 

 is reiterated illustration of Organisms functioning in their environ- 

 ments, and of Environments impressing their influences on organisms. 

 And hence, for each and every type of organism, we further seek to 

 appreciate, as far as may be, its Psycho-biosis as well as its Bio- 

 psychosis ; in other words, its Mind-body as well as its Body-mind. 



{d) Besides such expositions and orientations, we submit to the 

 reader various personal contributions, old and new, and outlined 

 a little more fully below — such as our Metabolic Theory of Sex, 

 conception of the Cell-Cycle, arrangement of the diverse types of 

 Animal Behaviour, and fuller analyses of various familiar biological 

 concepts, which have become somewhat conventionalised, such as 

 Reversion, Parasitism, and the Influence of the Environment. 

 Such contributions include, especially in the last quarter of the 

 book, many human and social applications of Biology — medical, 

 eugenic, educational, and even civic. 



VOL. I A 



