218 THE LESSON OF EVOLUTION 



wall. It is an ideal flower and an ideal wall. If we 

 tried to draw them, they would be unlike anything 

 we had actually seen. So also with hallucinations. 

 " Is this a dagger that I see before me?" is typical 

 of a large number of facts. They are impressions 

 made on the brain without any external stimulus. 

 In somnambulism we have just the opposite ; a stimu- 

 lus without any mental impression being made. So 

 it is with a person under anaesthetics ; the eyes and 

 ears are open, sensations pass in the brain, but no 

 impression is made. With conceptions and hallu- 

 cinations the physical processes are absent ; in somn- 

 ambulism the mental processes are absent. How 

 then can they be called equivalents? In the second 

 place , do the processes take place in accordance with 

 unvarying laws which prevail throughout the 

 material universe? It is the opinion of many people 

 that reflex action is mechanical ; and I have even seen 

 it stated by a Professor of Biology that the stimulus 

 is the cause of reflex action. But a very little con- 

 sideration will shew that this is not exactly the case. 

 The fact that habits are formed gradually as the result 

 of experience shews that reflexes are not purely 

 mechanical, however much they may resemble 

 mechanical action. It is the same when the pro- 

 cess is in the opposite direction, and an instinctive 

 movement is gradually abandoned. For such is 

 often the case. The soldier in his first action ducks 

 his head when he hears a shell whistling through 

 the air ; but in time he becomes familiar with the 

 sound and no longer goes through the instinctive 

 but useless action. One of my granddaughters had 



