THE CAUSATION OF DISEASE. 329 



may be of a very palpable nature, and effect gross and 

 obvious alteration upon the nervous system. See what a 

 profound change rickets works upon the body : not a single 

 part escapes, and many of the tissues are quite as seriously 

 affected as the bones. That the nervous S} T stem is very 

 profoundly modified is clearly shown by the great tendency 

 to convulsions (which, as Dr. Gowers tells us, often lead to 

 epilepsy later in life), and also to laryngismus stridulus. 

 Dr. Barlow has never met with this disorder in a child that 

 was not rickety. 



There is no doubt that infantile convulsions and epilepsy 

 are due to cortical change. Indeed, it has often struck 

 me with wonder that pathologists, in seeking for the 

 primary seat of these diseases, have so persistently ignored the 

 large mass of cortical grey matter. Herein are situated the 

 highest and most elaborately constructed nerve-centres ; we 

 should therefore expect them to be the most unstable in 

 the body, the most easily unhinged and thrown out of gear. 

 Why, therefore, seek for the primary cause of such diseases 

 as epilepsy, hysteria, and chorea in the lower inferior reflex 

 centres, which common sense should tell us must be more stable 

 than the more highly evolved and supreme cortical centres, and 

 which collectively form in weight but a small fraction of the 

 cortical grey matter ? But this by the way. Now, seeing that 

 rickets works a profound change upon the cortical grey matter, 

 it is obvious that the mental powers of a rickety individual 

 must suffer from this disorder. Would Shakespeare have been the 

 man he was if the first few years of his life had been spent 

 in a dark and narrow London alley, even though his subse- 

 quent E had been that which he actually experienced ? I have 

 no hesitation in answering this question in the negative. 

 Rickets must necessarily have resulted from the early E, and 

 this disorder would have wrought a profound change in the 

 cortical grey matter of that remarkable brain ; there would 

 have been serious disturbance with the finer developmental 

 changes, and thus the proper progress of mind-evolution 

 would have been interfered with. In estimating the differences 

 in the intellectual traits of brothers and sisters, we must there- 

 fore be careful to take into account external influences. Many 



