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“ the mind may be put in such a train, that it shall perceive, by a kind of scientific sense, that propriety, which words can but very feebly suggest."
Application of the Principles stated in the foregoing Sec
tions of this Chapter, to explain the Phenomena of Dreaming
WITH respect to the Phenomena of Dreaming, three different questions may be proposed. First; What is the state of the mind in fleep? or, in other words, what faculties then continue to operate, and what faculties are then suspended ? Secondly ; how far do our dreams appear to be influenced by our bodily sensations; and in what respects do they vary, according to the different conditions of the body in health, and in sickness ? Thirdly; what is the change which sleep produces on those parts of the body, with which our mental operations are more immediately connected; and how does this change operate, in diversifying, so remarkably, the phenomena which our minds then exhibit, from those of which we are conscious in our waking hours ? Of these three queftions, the first belongs to the philosophy of the Hu. man Mind ; and it is to this question that the following inquiry is almost entirely confined. The sec: ond is more particularly interesting to the medical inquirer, and does not properly fall under the plan of this work. The third seems to me to relate to a subject, which is placed beyond the reach of the human faculties,
It will be granted, that, if we could ascertain the state of the mind in sleep, so as to be able to resolve
* Discourses by Sir Joshua Reynolds.
the various phenomena of dreaming into a smaller number of general principles ; and itill more, if we could resolve them into one general fact; we should be advanced a very important fiep in our enquiries upon this subject ; even although we should find it impofsible to shew, in what manner this change in the state of the mind results from the change which Sleep produces in the state of the body. Such a step would at least gratify, to a certain extent, that dispofition of our nature which prompts us to afcend from particular facts to general laws; and which is the foundation of all our philosophical researches ; and, in the present instance, I am inclined to think, that it carries us as far as our imperfect faculties enable us to proceed.
In conducting this inquiry with respect to the state of the mind in fleep, it seems reasonable to expe&, that fome light may be obtained from an examination of the circumstances which accelerate or retard its approach ; for when we are disposed to relt, it is natural to imagine, that the state of the mind approaches to its itate in fleep, more nearly, than when we feel ourselves alive and active, and capable of applying all our various faculties to their proper purposes.
In general it may be retrarked, that the approach of sleep is accelerated by every circumstance which diminishes or suspends the exercise of the mental powers ; and is retarded by every thing which has a contrary tendency. When we wish for fleep, we naturally endeavor to withhold, as much as possible, all the active exertions of the mind, by disengaging our attention from every interesting subject of thought. When we are disposed to keep awake, we naturally fix our attention on some subject which is calculated to afford employment to our intellectual powers, or to rouse and exercise the active principles of our nature,
It is well known, that there is a particular class of founds which compose us to sleep. The hum of bees; the murmur of a fountain ; the reading of an uninteresting discourse; have this tendency in a remarkable degree. If we examine this class of sounds, we shall find that it consists wholly of such as are fitted to withdraw the attention of the inind from its own thoughts; and are, at the fame time, not fufficiently interesting to engage its attention to themselves.
It is also matter of common observation, that chil. dren and persons of little reflection, who are chiefly occupied about sensible objects, and whose mental activity is, in a great measure, suspended, as soon as their perceptive powers are unemployed; find it extremely difficult to continue awake, when they are deprived of their usual engagements.
The fame thing has been remarked of savages, whose time, like that of the lower animals, is almost completely divided between sleep and their bodily exertions.*
From a confideration of these facts, it seems reafonable to conclude, that in fleep thofe operations of the mind are suspended, which depend on our volition ; for if it be certain, that before we fall asleep, we must withhold, as much as we are able, the exercise of all our different powers ; it is scarcely to be iniagined, that, as soon as sleep commences, these powers should again begin to be exerted. The more probable conclution is, that when we are desirous to procure sleep, we bring both mind and body, as nearly as we can, into that state in which they are to continue after sleep commences. The difference,
* « The existence of the Negro slaves in America, appears to 6 participate more of sensation than reflection. To this inust be “ ascribed, their disposition to sleep when abstracted froin their " diversions, and unemployed in their labor. An animal whose “ body is at rest, and wlio does not reflect, must be disposed to
sleep of course." Notes on Virginia, by MY. JEFFERLON, P. 255.
therefore, between the state of the mind when we are inviting sleep, and when we are actually asleep, is this ; that in the former case, although its active exertions be suspended, we can renew them, if we please. In the other case, the will loses its influence over all our powers both of mind and body; in consequence of some physical alteration in the system, which we shall never, probably, be able to explain.
In order to illustrate this conclusion a little farther, it may be proper to remark, that if the fufpenfion of our voluntary operations in fleep be admitted as a fact, there are only two suppositions which can be formed concerning its cause. The one is, that the power of volition is suspended ; the other, that the will loses its influence over those faculties of the mind, and those members of the body, which, during our waking hours, are subjected to its authority. If it can be Thewn, then, that the former supposition is not agreeable to fact, the truth of the latter feems to fol. low as a necessary consequence.
1. That the power of volition is not suspended during fleep, appears from the efforts which we are conscious of making while in that situation. We dream, for example, that we are in danger ; and we attempt to call out for aslistance. The attempt, indeed, is, in general, unfuccessful; and the sounds which we emit, are feeble and indistinct; but this only confirms, or, rather, is a necessary confequence of the supposition, that, in sleep, the connection between the will and our voluntary operations, is disturbed, or interrupted. The continuance of the power of volition is demonstrated by the effort, however ineffectual.
In like manner, in the course of an alarming dream,we are sometimes conscious of making an ex.ertion to save ourselves, by flight, from an apprehend! ed danger ; but in tpite of all our efforts, we contin
ue in bed. In such cafes, we commonly dream, that we ate attempting to efcape, and are prevented by fome external obstacle ; but the fact seems to be, that the body is, at that time, not subject to the will. During the difturbed reft which we fometimes have when the body is indisposed, the mind appears to retain some power over it; but as, even in thefe cases, the motions which are made, confift rather of a general agitation of the whole system, than of the regular exertion of a particular member of it, with a view to produce a certain effect ; it is reafonable to conclude, that, in perfectly found sleep, the mind, although it retains the power of volition, res tains no influence whatever over the bodily organs.
In that particular condition of the fyftem, which is known by the name of incubus, we are conscious of a total want of power over the body : and, I be. lieve, the common opinion is, that it is this want of power which distinguishes the incubus from all the other modifications of fleep. But the more probable supposition feems to be, that every species of sleep is accompanied with a suspension of the faculty of voluntary motion, and that the incubus has nothing peculiar in it but this, that the unexiy sensations which are produced by the accidental posture of the body, and which we find it impossible to remove by our own efforts, render us distinctly conscious of our incapacity to move. One thing is certain, that the instant of our awaking, and of our recovering the command of our bodily organs, is one and the fame.
2. The same conclusion is confirmed by a different view of the subject. It is probable, as was al. ready observed, that when we are anxious tó procure sleep, the state into which we naturally bring the mind, approaches to its ftate after fleep commences. Now it is manifeft, that the means which náture directs us to employ on such occafions, is not to