THE MEANING OF HEALTH 263 



Another conception of evil spirits has appeared from time to 

 time, in which "spirit" corresponds less to a devil or an organ- 

 ism than to ideas or thought. Thus, many people believe that a 

 disorder of the body may be brought about by evil thoughts, 

 either on the part of the patient himself or on the part of some 

 wicked enemy. This kind of belief is hard to handle, because 

 it has to do with matters that do not lend themselves to experi- 

 menting. It would be very hard for you to prove, for example, 

 that my toothache was not caused by someone's throwing tooth- 

 ache thoughts at me while I was asleep. Nevertheless the health 

 of the body and the health of the mind are closely connected. 



216. Physical basis of mental disturbances. Most of us are 

 unable to keep our minds on our work when we have any kind 

 of pain, whether it is a slight bruise or a jumping toothache. 

 When the liver is out of order, it is almost impossible for most 

 people to maintain a cheerful mood ; we have the blues, or we 

 are grouchy or irritable. ]\Ien have committed acts of folly and 

 of violence when under the influence of alcohol or other drugs. 

 When one is exhausted from hunger or fatigue, not only does the 

 mind work at lower pressure, but there may be even uncon- 

 trolled images or wild thinking. Just as the chemical condi- 

 tion of the blood may change the rate of breathing and influence 

 the digestive organs, so it may influence the brain and mental 

 processes. People have become insane and irresponsible from 

 the poisoning of the blood by physical disease, or by alterations 

 in the quantities or the relative quantities of the internal secre- 

 tions. So we cannot help recognizing that the mind may be 

 influenced by physical conditions of the body. 



217. Mental effects on physical conditions. Now we have to 

 see that the opposite may be just as true. A person who is very 

 much excited by some good news or bad news is likely to suffer 

 from indigestion ; a person who is worried is likely to become 

 run down physically. A cheerful frame of mind keeps up the 

 action of the blood ; a hopeful disposition enables a sick person 

 to get well more rapidly. In some cases of mental disturbance or 

 insanity the bowels fail to carry on their work or the breathing 



