PREFACE 



OUR recently gained knowledge of the endocrine 

 glands, their secretions and their functions, has 

 opened up entirely new vistas of life and its con- 

 trolling directing mechanism. This knowledge is, 

 of course, rudimentary, but already we perceive 

 a new science of therapeutics, physiological and 

 rational in its conceptions and actions : this new 

 science fulfils also the original meaning of thera- 

 peutic in that it includes the prevention as well 

 as the cure of disease, the way of health, the way 

 of life versus death. Of late years we have been 

 worshipping the power of the will, and have been 

 concentrating perhaps too much on the develop- 

 ment of that power ; often, it must be confessed, 

 with happy results. In doing this we have been 

 tempted to neglect the marvellous power and 

 scope of the vegetative system. Our will directs 

 our movements, and to a large extent our thoughts 

 and actions, but the great laboratory work of life, 

 silent and almost unseen, is carried on outside will 

 and even outside consciousness. 

 A rough but instructive parallel may be drawn 



