MALIGNANCY 39 



logists been apt to regard the cessation of invasion at 

 a given stage asa" natural " fact, i.e. just the result to be 

 expected of that kind of cell or tissue ? But to cease 

 growing means either a failure of energy or inhibition, and 

 growth must be analysed into excitation and inhibition. 

 In a very true sense " malignancy " or invasiveness is char- 

 acteristic of all growing tissue. It is not a wild illustration 

 to point out that in society we are all potential criminals at 

 the mercy of excitation and inhibition, nor otiose to observe 

 that the liability to crime on the part of aliens in this or any 

 country is due to unaccustomed stimulation and the lack 

 of former inhibitions. Such criminality is an analogue of 

 malignancy. I owe to Professor Keith the suggestion that 

 the negro in the United States is even a better example. 

 The negro community there is as much a transplanted tissue 

 as a cancer metastasis, it tends to spread, excites violent 

 reactions, and might conceivably prove definitely malignant. 

 I am aware that the remark may excite ridicule ; but it can 

 be pointed out that the reaction against the immigrant 

 negro in the north is comparatively slight, and that when 

 trouble occurs it is very frequently due to the presence of a 

 Southerner who, by his previous contact with the race, 

 has been "sensitized " so as to react violently. Without 

 desiring to push the analogy to its farthest extreme, it is 

 obvious that a large negrine irruption tends to break up and 

 push apart previous social bonds and regulations. I do 

 not see how it can be denied that such illustrations help 

 us to understand the more obscure somatic phenomena. 



It must be quite obvious by now that the views here 

 advocated link the general theory of malignancy to the 

 doctrine of the endocrine organs, that glandular hierarchy 

 or pantheon which rules growth and metabolism. When 

 we observe that the absence of a particular secretion limits 



