II 



HOKMONES 



IN olden times the theory and practice of 

 medicine was more or less permeated by the 

 doctrine of the humors. Those of you who 

 are conversant with medical history will recall 

 that, according to this doctrine, there were 

 supposed to be four cardinal humors : blood, 

 yellow bile or choler, phlegm, and black bile. 

 Many distempers of mind and body were at- 

 tributed to disturbances in these fluids, and 

 their conditions and proportions were sup- 

 posed to determine the physical and mental 

 qualities as well as the disposition of the indi- 

 vidual. Various kinds of insanity, known un- 

 der the general name of melancholy, were 

 supposed to be associated, as this term implies, 

 with the black bile. And we still describe tem- 

 peraments as sanguine, choleric, or phleg- 

 matic. But with the growth of our knowledge 

 of the nervous system and with the recognition 

 of its significance as the chief means of con- 

 trol for the body as well as the seat of person- 



