EVIDENCE PROVING THE STATEMENT OF THE CASE 121 



Now, the fundamental facts to fix our minds on are 

 these : 



Firstly, the greater the number of cells there are in 

 the cortex of the brain, if they are healthy, providing 

 they are properly connected up with the fibres of the 

 nervous matter all over the body, the higher the mental 

 power of the individual becomes. 1 



the process is essentially the same, though more complicated. The 

 message is transmitted to the brain, where it is received by a cluster 

 of small sensory cells or nerve-centres, which are connected with 

 another cluster of fewer and larger motor-centres, often at some 

 distance from them, by a network of interlacing fibres. But it is 

 always a case of a single circuit of wires, batteries, and accumulators, 

 adapted for receiving, recording, and transmitting one sort of vibra- 

 tions caused by and producing one sort of energy, and one only. The 

 brain does not act as a whole, receiving indiscriminately impressions 

 of light, sound, and heat ; but by separate organs for each, located in 

 separate parts of it. 1 1 is like a great central office, in one room of 

 which you have a printing instrument reading off and recording 

 messages sent through an electric telegraph ; in another a telephone ; 

 in a third a self -registering thermometer, and so on. And the same 

 for the motor-centres and nerves. One set is told off to move the 

 muscles of the face, another those of the arms, others for the legs 

 and body, and so forth." (" A Modern Zoroastrian," S. Laing, 1895, 

 p. 129.) 



1 " The extent of the convolutions is, therefore, a sure sign of the 

 extent of intellect. They are more numerous and deeper in the 

 European than in the negro ; in the negro than in the chimpanzee ; 

 in the anthropoid ape than in the monkey or lemur. This -grey 

 nerve-tissue is the organ by which impressions from without are 

 turned into perceptions, volitions, and evolutions of nerve force. The 

 white matter is simply the medium of transmission, or we may say 

 the telegraph wires by which the impressions are conveyed to the 

 head office and the answers sent. The cell- tissue of the grey matter 

 is thus emphatically the organ of the mind. In fact, if it did not 

 sound too materialistic, we might call thought a secretion of the grey 

 matter, only in saying so we must bear in mind that it is only a mode 



