712 THE POPULAR SCIENCE MONTHLY. 



very higa authority, a contradiction in terms. But all the facts ad- 

 duced by Dr. Carpenter to i^rove unconscious cerebration are dis- 

 tinctly mental changes such as. according to Mill, it is a contradic- 

 tion in terms to designate as unconscious. 



These mental changes may be classed almost entirely under two 

 heads : 1. Recollection without effort ; and, 2. Apparent increase in 

 the results of thought without further thought. 



It may be taken as one of the commonest mental experiences of 

 most men, that a fact, and especially a name, which they endeavor 

 to remember, which escapes from the determinate eifort of recol- 

 lection, often suddenly jumps, as it were, into the recollection 

 without effort, after they have been thinking of other matters. Dr. 

 Carpenter explains this by the theory that the part of the brain 

 engaged in storing up and reproducing past impressions is not the 

 same part of the brain which is engaged in the consciousness of those 

 impressions, or in the consciousness of their reproduction ; and that 

 after the seat of consciousness has given up its futile labor, the seat 

 of memory unconsciously continues its activity, and when it has un- 

 consciously brought its work to a successful issue it communicates 

 the result to the seat of consciousness ; then, and not before, the fact 

 is consciously remembered. Upon this we must remark that the con- 

 scious effort to command the memory, without guide or clew, is gen- 

 erally and singularly unsuccessful in result. The only way to succeed 

 in remembering some forgotten thing is to seek some clew, some thread 

 of ideal association which may lead us to it. The direct bald effort 

 fails, for the simple reason that the attention is fixed upon the effort, 

 and not upon the idea sought. Withdraw the effort, and the atten- 

 tion fixes upon the idea. The memory of the thing was in the brain, 

 must have been there all the time, or it could never again have been 

 remembered. Memory is a latent j)Ower, and always unconscious. 

 Recollection is the mental activity which opens the cells of memory 

 to the consciousness and recollection, therefore must always be con- 

 scious. That any portion of brain-work is done unconsciously in the 

 act of recollection, is a theory to which we cannot subscribe without 

 far stronger evidence than any which we have yet seen adduced. 



The second class of facts adduced to prove that mental work can 

 be performed by the brain without consciousness, are almost as com- 

 mon among men who are in the habit of employing their minds in in- 

 tricate and difficult subjects. A man thinks on some matter which 

 needs to be considered from various points of mental view, which ap- 

 pears to have bearings on many other subjects which seem to need 

 elucidation from many quarters ; he turns all the mental material 

 over and over again until the whole business seems a jumble, and, in 

 confusion and weariness of thought, he puts it aside. He sleeps upon 

 it, and the next day that which overnight was a daub of confused 

 colors, is seen as a bright and clear mental picture. The instances 



