CHAPTER I 



INTRODUCTION: THE FIELD AND PROBLEMS 

 OF BIOLOGY 



Whatever else man may be — a rational, a social, or a religious being — 

 he is also a living organism. Along with more than a million other kinds of 

 living things, he is composed of the intricate stuff called protoplasm. Like 

 them he is subject to the peculiar laws that govern the existence and 

 functioning of this living substance. Underlying such aspects of human 

 conduct as are the special concern of history, sociology, and economics 

 are the fundamental attributes, capacities, and limitations that are 

 inherent in man's organic make-up and his membership in the company 

 of living things. This book is concerned with some of the basic principles 

 that have been found to apply to living things and that help us better 

 to understand ourselves and the world in which we live. 



The field of knowledge that relates primarily to life processes and living 

 things as such, is known as biology. 1 This science seeks to discover and 

 describe all the phenomena associated with living things and the state of 

 being alive. It has amassed a huge content of facts, hypotheses, and 

 principles that give us an insight into the conditions of man's existence, 

 his limitations, and his potentialities. But even if our only interest in 

 biology were to discover the principles that govern human existence and 

 welfare, we could not profitably or efficiently confine our attention to 

 man. He is one of the most complex of all organisms; he is unavailable 

 for many kinds of experiment and observation ; and much of his biological 

 make-up is modified or concealed by his intellectual and social attain- 

 ments. Most of our surest knowledge of man has been gained, and can 

 best be tested, by turning to other forms of life that are more available 

 for experiment and safer for objective observation. Indeed, we cannot 

 adequately understand man's biological heritage and background without 

 some appreciation of the whole living world — in which he lives, of which 

 he is a part, and which he must in some measure control and exploit. 



1 This word comes from the Greek bios, meaning "life," and logos, which literally- 

 meant "the word," "a discourse," or "the discussion of," and which has come to 

 mean "the science of." 



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