796 OF THE FUNCTIONS OF THE NERVOUS SYSTEM. 



experience of subsequent fatigue, a very strong indication that the power which 

 thus controls and directs the current of thought, is of the same kind with that 

 which calls forth Volitional movements of the body, though exerted in a different 

 mode. And just as the strongest exertion of Will is required to produce or 

 sustain Muscular contraction, when the sense of muscular fatigue is already 

 strongly experienced, or when we are antagonizing a powerful automatic impulse, 

 so, in the determination of Mental effort in a particular direction, we find our- 

 selves necessitated to make the greatest Volitional effort when we are already 

 laboring under the sense of cerebral fatigue, or when the attention is powerfully 

 solicited by some other attractive object. And it is after any such contest with 

 our natural tendencies, that we experience the greatest degree of exhaustion j 

 the merely automatic action of the Mind, which is attended with no effort, being 

 followed by comparatively little fatigue. 1 



824. But this determining power of Volition is employed, in however slight 

 a degree, whenever the succession of thought is not perfectly spontaneous ; a 

 whenever, in fact, we wish our consciousness to take a particular direction, even 

 for the apprehension of ideas most familiar to our minds. Of this we derive the 

 best evidence from those curious states in which the directing power of the Will 

 is entirely suspended, whilst yet the mind remains freely open to external im- 

 pressions ; a .condition which shows us what we should be, if we really were what 

 some writers assure us that we actually are, mere thinking automata, puppets 

 moved in any direction by the pulling of suggesting strings ( 802, note). This 

 condition presents itself spontaneously in some individuals, and may be induced 

 in others ; and it is not a little remarkable that it may occur as a modification 

 both of the waking and the sleeping states. Of the former we have an example 



1 The author is satisfied, from his own experience, that a most valuable indication may 

 be hence drawn, in regard to the regulation of the habits of Intellectual labor. To indivi- 

 duals of ordinary mental activity, who have been trained in the habit of methodical and 

 connected thinking, a very considerable amount of work is quite natural ; and when such 

 persons are in good bodily health, and the subject of their labor is congenial to them 

 especially if it be one that has been chosen by themselves because it furnishes a centre of 

 attraction around which their thoughts spontaneously tend to range themselves their 

 intellectual operations require but little of the controlling or directing power of the Will, 

 and may be continued for long periods together without fatigue. But from the moment 

 when an indisposition is experienced to keep the attention fixed upon the subject, and the 

 thoughts wander from it unless coerced by the Will, the mental activity loses its sponta- 

 neous or automatic character ; and more exertion is required to maintain it volitionally 

 during a brief period, and more fatigue is subsequently experienced from such an effort, 

 than would be involved in the continuance of an automatic operation through a period 

 many times as long. Hence he has found it practically the greatest economy of mental 

 labor, to work vigorously when he feels disposed to do so, and to refrain from exertion, so 

 far as possible, when it is felt to be an exertion. Of course this rule is not applicable to all 

 individuals, for there are some who would pass their whole time in listless inactivity if not 

 actually spurred on by the feeling of necessity ; but it holds good for those who are sufficiently 

 attracted by objects of interest before them, or who have in their worldly circumstances a 

 sufficiently strong motive to exertion, to make them feel that they must work, the question 

 with them being how they can attain their desired results with the least expenditure of 

 mental labor. 



2 It is hoped that the reader will have been made sufficiently aware, by the preceding 

 explanations, that by the terms "spontaneous" or "automatic" succession of thought, it 

 is intended to designate that sequence of states of consciousness, in which every one is the 

 immediate resultant of that which preceded it, whether that were ideational or sensational. 

 Thus the current of thought is alike " spontaneous," when it flows onwards in one continuous 

 channel, being directed by a single dominant idea which absorbs the whole attention ; and 

 when the mind is freely accessible to external impressions, and may be entirely guided by 

 them. The phenomena of Reverie, Abstraction, and Somnambulism (as will be presently 

 seen) afford illustrations of both these states ; which, though apparently opposite in their 

 nature, are really characterized by the same essential feature, namely, the absence of the 

 directing power of the Will. 



