Dominant Ideas. 797 



piece of floating wreck. " Such delusions are common. They originate 

 in the cerebrum, while pure illusions are probably due to improper re- 

 actions of the sensory ganglia. 



But suggestion also plays an important part in all the ordinary ac- 

 tions of life, as in fashions, dress, manners, modes of thought, language, 

 &c. If a newsboy enters a crowded street car it may happen that he will 

 run the gauntlet between the long seats without selling a paper. If, as 

 he is about to get off, a passenger calls him back and buys a paper, the 

 act becomes a suggestion, and probably half a dozen others will do the 

 same. In signing a subscription paper or a petition, the subscribers are 

 often moved by nothing else than the names already signed. 



Another phenomenon of kindred sort is the automatic and uncon- 

 scious conversion of a suggestion into motor action in our own muscles. 

 This is called Expectant Attention. If a person will hold, attached to 

 his thumb, a button suspended by a string, in such a position that its 

 oscillations would make it strike a glass tumbler, he will find that he can 

 not hold it quite still, even by the greatest effort. If he is not too 

 positive and skeptical, an assurance or expectation that the button will 

 strike the hour of the day will very likely be realized. The muscles 

 will be influenced by the conviction, and perform the oscillations through 

 an unconscious will. The number struck will tally with the performer's 

 idea of the time of day. The motions of the hand are governed by this 

 idea. That is, the will is insensibly dominated by that idea, and the 

 further idea that this number will be struck upon the glass. There is 

 nothing violent in this theory; it corresponds with what is ascertained to 

 be the operation of the will in other examples. The great majority of 

 our actions are miscalled involuntary, because they are performed with- 

 out arousing consciousness. But, after making due allowance for those 

 which are stimulated by the lower parts of the spinal axis, and the sen- 

 sory ganglia, in what are called reflex and consensual actions, there are 

 still a good many in the stimulation of which the cerebral ideas form a 

 constituent element. If the operator should close his eyes, so as not to 

 see whether the vibrations were regular or not, they would become irreg- 

 ular. In short, the result will accord with the idea of the operator. 

 The same explanation properly accounts for th-^ practice with the divin- 

 ing-rod, an instrument made of a forked hazel stick, by which subter- 

 ranean currents of water, and deposits of metal, are pretended to be 

 discovered. If the party using it has faith, the rod will point to the 

 place where he expects to find the deposits he seeks, or if he has no 

 opinion on that score, after his muscles have, for some time, been held 

 in one positon, they will begin to move spasmodically, whereupon the 

 operator, perceiving the twitching of the rod, has his expectation raised 

 that the performance is about to begin, which expectation becomes, of 



