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ceptions of sight are found from experience to be the signs. The notions therefore we form, by means of the eye, of the tangible qualities of bodies, and of the distances of these objects from the organ, are mere conceptions; strongly, and indeed indissolubly, associated, by early and constant habit, with the original perceptions of sight. When we open our eyes on a magnificent prospect, the various distances at which all its different parts are placed from the eye, and the immense extent of the whole scene before us, seem to be perceived as immediately, and as instantaneously by the mind, as the coloured surface which is painted on the retina. The truth, however, unquestionably is, that this variety of distance, and this immensity of extent, are not objects of sense but of conception; and the notions we form of them when our eyes are open, differ from those we should form of them with our eyes shut, only in this, that they are kept steadily in the view of the mind, by being strongly associated with the sensations of colour, and with the original perceptions of sight.—This observation will be the more readily admitted, if it be considered, that, by a skilful imitation of a natural landscape in a common shew-box, the mind may be led to form the same notions of variety of distance, and even of immense extent, as if the original scene were presented to our senses: and that, although, in this case, we have a speculative conviction that the sphere of our vision only extends to a few inches, yet so strong is the association between the original perceptions of sight, and the conceptions which they habitually produce, that it is not possible for us, by any effort of our will, to prevent these conceptions from taking place. From these observations it appears, that when the conceptions of the mind are rendered steady and permanent, by being strongly associated with any sensible impression,
they command our belief no less than our actual perceptions; and, therefore, if it were possible for us, with our eyes shut, to keep up, for a length of time, the conception of any sensible object, we should, as long as this effort continued, believe that the object was present to Our Senses. . It appears to me to be no slight confirmation of these remarks, that although, in the dark, the illusions of imagination are much more liable to be mistaken for realities, than when their momentary effects on the belief are continually checked and corrected by the objects which the light of day presents to our perception, yet, even total darkness is not so alarming to a person impressed with the vulgar stories of apparitions, as a faint and doubtful twilight, which affords to the conceptions an opportunity of fixing and prolonging their existence, by attaching themselves to something which is obscurely exhibited to the eye.—In like manner, when we look through a fog, we are frequently apt to mistake a crow for a man; and the conception we have, upon such an occasion, of the human figure, is much more distinct and much more steady, than it would be possible for us to form, if we had no sensible object before us; insomuch that when, on a more attentive observation, the crow shrinks to its own dimensions, we find it impossible, by any effort, to conjure up the phantom which a moment before we seemed to perceive. If these observations are admitted, the effects which exhibitions of fictitious distress produce on the mind, will appear less wonderful than they are supposed to be. During the representation of a tragedy, I acknowledge, that we have a general conviction that the whole is a fiction, but, I believe, it will be found, that the violent emotions which are sometimes produced by the distresses of the stage, take their rise, in most cases, from a momentary belief, that the distresses are real. I say, in most cases, because I acknowledge, that independently of any such belief, there is something contagious in a faithful expresssion of any of the passions. The emotions produced by a tragedy are, upon this supposition, somewhat analogous to the dread we feel when we look down from the battlement of a tower.” In both cases, we have a general conviction, that there is no 'ground for the feelings we experience, but the momentary influences of imagination are so powerful as to produce these feelings, before reflection has time to come to our
* With respect to the dread which we feel in looking down from the battlement of a tower, it is curious to remark the effects of habit in gradually destroying it. The manner in which habit operates in this case, seems to be by giving us a command over our thoughts, so as to enable us to withdraw our attention from the precipice before us, and direct it to any other object at pleasure. It is thus that the mason and the sailor not only can take precautions for their own safety, but remain completely masters of themselves in situations where other men, engrossed with their imaginary danger, would experience a total suspension of their faculties. Any strong passion which occupies the mind produces, for the moment, the same effect with habit. A person alarmed with the apprehension of fire, has been known to escape from the top of a house, by a path which, at another time, he would have considered as impracticable; and soldiers, in mounting a breach, are said to have sometimes found their way to the enemy, by a route which appeared inaccessible
after their violent passions had subsided.
General observations on this Faculty of the Mind.
The origin of appellatives, or, in other words, the origin of those classes of objects which, in the schools, are called genera, and species, has been considered by some philosophers as one of the most difficult problems in metaphysics. The account of it which is given by Mr. Smith, in his Dissertation on the Origin of Languages, appears to me to be equally simple and satisfactory. *
“The assignation” (says he) “ of particular names, to “denote particular objects; that is, the institution of “nouns substantive, would probably be one of the first “steps towards the formation of Language. The par“ticular cave, whose covering sheltered the savage from “the weather; the particular tree, whose fruit relieved his “ hunger; the particular fountain, whose water allayed his “thirst; would first be denominated by the words, cave, “tree, fountain; or by whatever other appellations he “might think proper, in that primitive jargon, to mark “them. Afterwards, when the more enlarged experience “of this savage had led him to observe, and his necessary “occasions obliged him to make mention of, other caves, “ and other trees, and other fountains; he would naturally “bestow upon each of those new objects, the same name “by which he had been accustomed to express the similar “object he was first acquainted with, And thus, those
WOL., I, 17
“words, which were originally the proper names of indi“viduals, would each of them insensibly become the com“mon name of a multitude.”* “It is this application” (he continues) “of the name of “an individual to a great number of objects, whose resem“blance naturally recalls the idea of that individual, and of “the name which expresses it, that seems originally to “have given occasion to the formation of those classes, and “assortments, which, in the schools, are called genera “ and species; and of which the ingenious and eloquent “Rousseau finds himself so much at a loss to account for “the origin. What constitutes a species, is merely a “number of objects, bearing a certain degree of resem“blance to one another; and, on that account, denomi“nated by a single appellation, which may be applied to “express any one of them.”f This view of the natural progress of the mind, in forming classifications of external objects, receives some illustration from a fact mentioned by Captain Cook in his account of a small island called Wateeoo, which he visited in sailing from New Zealand to the Friendly Islands. “The inhabitants,” says he, “were afraid to come near “our cows and horses, nor did they form the least con“ception of their nature. But the sheep and goats did “not surpass the limits of their ideas; for they gave us “to understand that they knew them to be birds. It “will appear,” he adds, “rather incredible, that human
* The same account of the progress of the mind in the formation of genera, is given by the Abbé de Condillac.
“Un enfant appelle du nom d'Arbre le premier arbre que nous lui montrons. Un second arbre qu'il voit ensuite lui rapelle la méme idée; illuidonnele même nom; de même à un troisième, a un quatrième, et voilà le mot d'Arbre donné d'abord à un individu, qui devient pour lui un nom de classe ou de genre, une idee abstraite qui comprend tous les arbres en général.”
# Dissertation on the Origin of Languages, annexed to Mr. Smith's Theory of Morak Sentiments.