52 SEX AND HEREDITY 



a street corner in any one of our great cities. If you ask 

 one of the individuals concerned who and what he is 

 he may reply that he is a worker though the most careful 

 watching may fail to detect any signs of a desire to work. 

 What is the man really doing ? Standing up what 

 more simple ? 



But now suppose you had the body of that same man 

 frozen stiff with every bit of him in precisely the same 

 position as it has been during life and suppose you now 

 stood him up on his feet on the same bit of flat pavement. 

 You would find considerable difficulty in getting him 

 balanced so as to stand up at all, and if at last you did 

 succeed you would find that the slightest touch, or a slight 

 breeze, would overturn him. And you would learn the 

 lesson that there is something: essentiallv different between 



{j J 



the standing up of that mass of dead material and the 

 standing up of the living man. As a matter of fact, when 

 you look into the mere action of standing up you find 

 that it is a matter of fearsome complexity. 



Suppose you had a chain of iron or wooden rods, jointed 

 loosely together end to end, you might be able with a 

 good deal of trouble to arrange it so as to be kept upright 

 by elastic bands passing from one rod to another and 

 each under exactly the proper degree of tension. Xow 

 this is the sort of principle which is at work in the living 

 human body the rods are represented by the bones of 

 the skeleton and the elastic bands by the muscles which 

 pass from one bone to another and pull against one another 

 so as to keep the whole arrangement upright. But what 

 puts the human arrangement upon a totally different 

 level of complexity as compared with the rough model 

 I have described is that it is automatic and self-regulating. 

 The equilibrium of the body is constantly being interfered 



