

THE CEREBRUM, AND ITS FUNCTIONS. 763 



794. The influence of Emotional conditions, when strongly excited, in directly 

 producing involuntary movements, is readily explained on the idea that the Sen- 

 sory Ganglia are the seat of all consciousness, and the Cranio- Spinal axis the 

 real source of all movement. For there is no more difficulty in understanding 

 that the excitement of peculiar states of consciousness in the Sensorial centres, 

 through the instrumentality of the Cerebrum, should give rise to automatic 

 movements, than that such movements should follow similar states of conscious- 

 ness when excited by impressions made upon the organs of vision, hearing, &c. 

 And the correspondence is seen to be very close, when the idea (as is doubtless 

 the case in some instances) is very nearly akin to the sensation. Thus, the 

 laughter excited by the act of tickling is a purely consensual movement ( 748) ; 

 but, in a very " ticklish" person, the mere idea of tickling, suggested by point- 

 ing a finger at him, is sufficient to provoke it. So, again, laughter may be ex- 

 cited by odd sights or sounds which do not in themselves excite any emotional 

 state, and which we call " ludicrous' 7 merely because they do excite laughter ; 

 and the vivid recollection of these, being attended with a state of the sensorium 

 corresponding to that produced by the sensation, may give rise to the same in- 

 voluntary cachinnation. But laughter may also be excited by ideas that are much 

 more removed from actual sensations, as, for example, by those unexpected com- 

 binations of ideas of a purely intellectual nature, which we designate as " witty/ 

 and here, too, we may recognize the very same modus operandi. For the mere 

 sound or sight of the words excites no feeling of the ludicrous ; the sensation 

 must develop an ideational change ; and it is the latter alone, which, reacting 

 downwards upon the Sensorium, and there becoming associated with the feeling 

 of pleasure, gives rise to the impulse to laugh. The same might be shown to 

 be the case with regard to the act of Crying ; which may be either purely con- 

 sensual, being excited by painful sensations ; or may be induced by the vivid 

 recollection of past or the anticipation of future sensations; or may be excited 

 by ideas which have no direct relation to sensational states. Again, the move- 

 ments which take place under the violent excitement of the passions of Anger, 

 Lust, &c., are of the same involuntary character ; being directly prompted by 

 feelings which may be either excited by external sensations, or by internal ideas 

 more or less akin to them. Thus the passionate man who receives a blow in- 

 stinctively makes another blow in the direction from which it seemed to him to 

 come, without any thought of whether the blow was accidental or intentional j 

 and the idea of an insult, which is a source of mental disturbance, may excite 

 the very same movement, although no bodily suffering had been experienced. 

 In states of excessive sexual excitement, again, the desire, which arises out of 

 the idea of the object ( 772), produces involuntary movements corresponding 

 to those which are ordinarily linked on to the actual sensations alone. There 

 are many of the movements of Expression, which are referable in like manner 

 to states of consciousness, whether pleasurable or painful, which may arise either 

 from sensational or from ideational conditions. Thus the cheerful aspect of 

 some individuals is due to a sense of general physical well-being, and is al- 

 together discomposed by anything which disturbs this ; whilst, on the contrary, 

 it proceeds in others from a happy frame of mind (which may be partly the 

 result of original constitution, and partly of habitual self-direction), disposing 

 them to take the cheerful view of everything that affects themselves or others, 

 notwithstanding (it may be) great bodily discomfort. And the reverse aspect 



auditory or visual sensations produced by spoken or written words; but in the association 

 of pleasure with the ideas which these words call forth in the mind. A view of the nature 

 of the Emotional states which approaches more nearly to his own, though not developed 

 with the analytical precision of Mr. Mill's, is contained in the Rev. Sydney Smith's 

 "Lectures on Moral Philosophy;" which, although delivered early in the present century, 

 were not published until the year 1850. 



