THE CEREBRUM, AND ITS FUNCTIONS. 707 







senses," as we may designate (after Reil) the radiating fibres of the Cerebral 

 Hemispheres ( 564). And there is on the other hand an a priori improb- 

 ability that there should be two seats of consciousness, so far removed from 

 one another as the Sensory Ganglia and the vesicular surface of the Hemi- 

 spheres (for to their medullary substance no such attribute can be assigned 

 with the least probability) ; an idea which is quite at variance with that 

 very simple and familar class of phenomena, which consists in the recollec- 

 tions of sensations. For the remembered sensation is so completely the re- 

 production of the original, that we can hardly suppose the seat of the two to 

 be different; yet the act of recollection is clearly Intellectual, and therefore 

 Cerebral ; consequently, if we admit that the Sensory Ganglia are the seat 

 of the original sensation, we can scarcely but admit that they are also the 

 seat of that which is reproduced by the Cerebral act, a view which is fully 

 confirmed by the occurrence of automatic movements as consequences of its 

 recall ( 546). And a careful analysis of our own mental operations will 

 often supply evidence of the evolution of results, such as ordinarily proceed 

 from intellectual action, without any consciousness on our own parts of the 

 steps whereby these are attained. 



571. Without presuming, then, to affirm positively what cannot be proved, 

 it may be stated as a probable inference from the facts already referred to 

 that the Sensory Ganglia constitute the seat of consciousness, not merely for 

 impressions on the Organs of Sense, but also for changes in the cortical sub- 

 stance of the Cerebrum ; so that, until the latter have reacted downwards 

 upon the Seusorium, we have no consciousness either of the formation of 

 ideas, or of any intellectual process of which these may be the subjects. 

 Ideas, Emotions, Intellectual operations, etc., have of late been frequently 

 designated as " states of consciousness ;" and this psychological description 

 of them is in full harmony with the physiological account here given of the 

 material conditions under which they respectively occur. For as a Sensa- 

 tion is a state of consciousness excited through the instrumentality of the 

 Seusorium, by a certain change (e.g.) in the condition of the Retina, it is 

 not difficult to understand how a change in the condition of the Cerebrum 

 may excite, through the same instrumentality, that state of consciousness 

 which may be termed Ideational, 1 or that another change may produce the 

 Emotional consciousness, another the Intuitional consciousness, another the 

 Logical consciousness. And although it may be thought at first sight to be 

 a departure from the simplicity of Nature, to suppose that the Cerebrum 

 should require another organ to give us a consciousness of its operations, yet 

 we have the knowledge that the Eye does not give us visual consciousness, 

 nor the Ear auditory consciousness, unless they be connected with the Sen- 

 sory Ganglia; and in the end (the author feels a strong assurance) it will be 

 found much simpler to accept the doctrine of a common centre for sensational 

 and for what may be distinguished as mental consciousness, than to regard 

 two centres as distinct. 2 



1 The Author ventures to use this term, the meaning of which requires no expla- 

 nation, on the authority of Mr. James Mill, who remarks, "As we sav Sensation, 

 we might also say Ideation ; it would be a very useful word ; and there is no objection 

 to it, except the pedantic habit of decrying a new term. Sensation is the general 

 name for one part of our constitution [or rather for one state of our consciousness], 

 Ideation for another." (Analysis of the Human Mind, vol. i, p. 42 ) If the use of 

 the substantive Ideation be admitted, there can be no reasonable objection to the ad- 

 jective ideational. 



2 An interesting and suggestive paper by Mr. Lockhart Clarke, On the Nature of 

 Volition, will be found in Nos. 7, 8, and 9 of the Psychological Journal for ISH'J. 



