SUGGESTION IN THERAPEUTICS. 345 



a sudden fit of anger makes a mother's milk poisonous to her 

 child.* 



In general, an emotional storm or even an emotional mood, if 

 long continued, may have a profound effect upon the functioning 

 of the body. The cheerful emotions favor health; the depress- 

 ing emotions make the body fertile ground for the growth of 

 disease germs. Yet even this admission does not bring one much 

 nearer the point of interest; for, since the epoch-making dis- 

 coveries of Prof. James, of Harvard, and Prof. Lange, of Copen- 

 hagen, it has been known that what we call an. emotion is not 

 the cause but the feeling of those extensive bodily changes which 

 we regard as its expression, and to inquire into the effect of emo- 

 tions upon metabolism would lead me too far afield into the 

 general theory of emotion. 



To account for the more remarkable effects of suggestion upon 

 metabolism we are forced to a most extraordinary hypothesis, 

 which may be thus stated : 



The thought of any given bodily change, whether motor, vaso- 

 motor, or metabolic, tends to the actual production in the body of 

 the change which that thought represents. 



That this law is true of motor thoughts I think quite clearly 

 proved. Of the vasomotor it is not so clearly true, but there is a 

 considerable amount of evidence going to show that the blood tide 

 can be to some extent directed by act of will by most persons, 

 and by some persons to a much greater extent. The evidence for 

 any control over the metabolic processes is very scanty. If the 

 tendency exists, it must be latent in most persons, for we all know 

 that I can not by thinking add a cubit to my stature or change 

 the color of my beard. Yet, even though it be latent in most 

 persons, it may exist in others, and I think the evidence for its ex- 

 istence is strong. The chief difficulty in accepting it lies in this : 

 we know of no nervous mechanism by which such central pro- 

 cesses can affect the body unless it be through the sensory nerves, 

 and, according to our present physiology, .sensory nerves can 

 carry impulses in one direction only. 



I can not explain these difficulties and shall not attempt to. I 

 shall simply relate the more important bits of evidence which 

 have been gathered since the 12th of May, 1885, when M. Focachon 

 performed his first successful experiment under satisfactory con- 

 ditions before the professors of the Medical School at Nancy. 

 Most of this evidence is experimental and it deals with modifica- 

 tions of the skin only. I do not suppose that this fact proves that 

 the control of thought over the skin is greater than that which 

 it exercises over the internal organs, but merely that experiments 



* Carpenter, Mental Physiology, 566. 

 vol. xlix. 29 



