598 CEREBRAL MENTAL SUBSTRATA. 



regards visible movements and visible form, the muscular con- 

 sciousness, it is now contended, is the indispensable element; 

 the optical sensations merely guiding the movements. Naked 

 outlines, as the diagrams of Euclid and the alphabetical charac- 

 ters are, to say the least, three parts muscular and one part 

 optical, their retention is supposed to depend upon the adhesive 

 property of the ocular muscles and their nerve centres, and 

 not upon purely optical circles. The memory of a visible form, 

 as a rainbow, contains the consciousness of a muscular sweep; 

 the windings of a river which, in the actual view, have to 

 be followed by movements of the eye, are remembered as ideal 

 movements." 



Without questioning the undoubted fact, that the movements of 

 a sensory organ must greatly increase the variety of impressions 

 derivable therefrom, or that they may contribute notably to generate 

 in the mind of the individual the fundamental notion of modes of 

 existence known as ' space,' ' time,' and ' resistance,' it is nevertheless 

 open for each one of us to form his own opinion as to the extent to 

 which ' muscular consciousness ' reveals itself to us as interwoven 

 with our ordinary sight impressions, and many ma} r perhaps be 

 inclined to think they can detect far less of it than Prof. Bain. 

 It is also open to each one of us to take a different view as to 

 the meaning and nature of what Prof. Bain here speaks of as ' mus- 

 cular consciousness.' He, we know, regards it as a ' concomitant 

 of the outgoing current,' and upon this basis considers it to be 

 radically opposed to all other modes of sensibility though this is 

 a view which others have just as decidedly rejected. 



For those, however, who entertain this disbelief in the existence 

 of a ' muscular sense ' or ' muscular consciousness ' as a concomi- 

 tant of the ' outgoing ' current, and who consider that the know- 

 ledge attributed to such an endowment has, in reality, been ac- 

 quired by means of ' ingoing ' impressions emanating from the 

 moving parts themselves, the revival in idea of such knowledge 

 must be as purely dependent upon the activity of Sensory Centres 

 as are the processes concerned with the revival in idea of particular 

 Odours. 



The seats of revival in idea of Movements of parts of the body 

 which are not seen (e.g., those of the larynx or of the eyes), are 

 the Kinaesthetic Centres alone ; whilst in the case of Movements 

 of parts of the body that are habitually seen Movements which 

 rave perhaps been learned under additional guidance from Vision 



