LECTURE XX. PARTICULAR CONSIDERATION OF OUR SENSATIONS.-NAMELESS TRIBES OF SENSATIONS-SENSATIONS OF SMELL-OF TASTE-OF HEARING. A CONSIDERABLE portion of my last Lecture, gentlemen, was employed in illustrating the corporeal part of the process of perception, which, though less immediately connected with our Science than the mental part of the process, is still, from its intimate connexion with this mental part, not to be altogether neglected by the intellectual inquirer. The importance of clear notions of the mere organic changes is, indeed, most strikingly exemplified in the very false theories of perception which have prevailed, and in some measure still prevail; and which evidently, in part at least, owe their origin to those confused notions, to which I alluded in my last Lecture, of the objects of perception, as supposed to operate at a distance through a medium, and of complicated series of changes supposed to take place in the nerves and brain. In considering the Phenomena of our Mind, as they exist when we are capable of making them subjects of reflection, I mentioned to you, in a former Lecture, that although we have to encounter many additional difficulties, in consequence of early associations, that modify for ever after our original elementary feelings, with an influence that is inappreciable by us, because it is truly unperceived, there are yet some advantages, which though they do not fully compensate this evil, at least enable us to make some deduction from its amount. The benefit to which I allude, is found chiefly in the class of phenomena which we are now considering,—a class, indeed, which otherwise we should not have regarded as half so comprehensive as it truly is, since but for our previous belief of the existence of a permanent and independent system of external things acquired from other sources, we should have classed by far the greater number of the feelings, which we now refer to sense, among those which arise spontaneously in the mind, without any cause external to the mind itself. Though the sensations which arise from affections of the same organ-as those of warmth and extension for example, or at least the feeling of warmth and a tactual feeling, that is commonly supposed to involve extension, from affections of the same nerves of touch,-are not, in every case, more analogous to each other, than the sensations which arise from affections of different organs, and though, if we were to consider the sensations alone, therefore, without reference to their organs, we might not form precisely the same classification as at present,-the division, according to the organs affected, in most cases corresponds, so exactly, with that which we should make, in considering the mere sensations as affections of the mind, and affords in itself a principle of classification, so obvious and definite, that we cannot hesitate in preferring it to any other which we might attempt to form. In the arrangements of every science, it is of essential consequence that the lines of difference, which distinguish one class from another, should be well marked; and this advantage is peculiarly important in the science of mind, the objects of which do not, as in the other great department of nature, outlast inquiry, but are, in every case, so very shadowy and fugitive, as to flit from us in the very glance, that endeavours to catch their almost imperceptible outline. In examining, then, according to their organs, our classes of sensation; and considering what feelings the organic affections excite at present, and what we may suppose them to have excited originally,-I shall begin with those which are most simple, taking them in the order of smell, taste, hearing,-not so much from any hope that the information which these afford will throw any great light on the more complex phenomena of sight and touch, as because the consideration of them is easier, and may prepare you gradually for this difficult analysis which awaits us afterwards in the examination of those more perplexing phenomena. I begin, then, with the consideration of that very simple order of our sensations which we ascribe to our organ of SMELL. THE organ of smell, as you well know, is principally in the nostrils,-and partly also in some continuous cavities on which a portion of the olfactory nerves is diffused. Naribus interea consedit odora hominum vis When the particles of odour affect our nerves of smell, a certain state of mind is produced, varying with the nature of the odoriferous body. The mere existence of this state is all the information which we could originally have received from it, if it had been excited previously to our sensations of a different class. But, with our present knowledge, it seems immediately to communicate to us much more important information. We are not merely sensible of the particular feeling, but we refer it, in the instant,-almost in the same manner, as if the reference itself were involved in the sensation,— to a rose, hemlock, honeysuckle, or any other substance agreeable or disagreeable; the immediate presence, or vicinity of which we have formerly found to be attended with this particular sensation. The power of making the reference, however, is unquestionably derived from a source different from that from which the mere sensation is immediately derived. We must previously have seen, or handled, the rose, the hemlock, the honeysuckle; or if, without making this particular reference, we merely consider our sensation of smell as caused by some unknown object external to our mind, we must at least have previously seen or handled some other bodies which excited, at the same time, sensations analogous to the present. If we had been endowed with the sense of smell, and with no other sense whatever, the sensations of this class would have been simple feelings of pleasure or pain, which we should as little have ascribed to an external cause as any of our spontaneous feelings of joy or sorrow, that are equally lasting or equally transient. Even at present, after the connexion of our sensations of a fragrance with the bodies which we term fragrant, has been, in a great measure, fixed in our mind, by innumerable reflections, we still, if we attend to the Gray de Principiis Cogitandi, Lib. I. v. 130-134. . process of the reference itself, are conscious of a suggestion of remembrance, and can separate the sensation, as a mere feeling of the mind, from the knowledge of the object or external cause of the sensation, which seems to us a subsequent state of the mind, however close the succession may be. Indeed, what is there which we can discover in the mere sensation of fragrance, that is itself significant of solidity, extension, or whatever we may regard as essential to the existence of things without? As a mere change in the form of our being, it may suggest to us the necessity of some cause or antecedent of the change. But it is far from implying the necessity of a corporeal cause; any more than such a direct corporeal cause is implied in any other modification of our being, intellectual or moral,-in our belief, for example, of the most abstract truth, at which we may have arrived by a slow developement of proposition after proposition, in a process of internal reflective analysis, or in the most refined and sublime of our emotions, when, without thinking of any one of the objects around, we have been meditating on the Divinity who formed them-himself the purest of spiritual existences. Our belief of a system of external things, then, does not, as far as we can judge from the nature of the feelings, arise from our sensations of smell, more than from any of our internal pleasures or pains; but we class our sensations of smell as sensations, because we have previously believed in a system of external things, and have found, by uniform experience, that the introduction of some new external body, either felt or seen by us, was the antecedent of those states of mind which we denominate sensations of smell, and not of those internal pains or pleasures, which we therefore distinguish from them, as the spontaneous affections of our own independent mind. ON TASTE. WITH the organ of taste you are all sufficiently acquainted. In considering the phenomena which it presents, in the peculiar sensations that directly flow from it, it is necessary to make some little abstraction from the sensation of touch which accompanies them, in consequence of the immediate application of the tangible sapid body to the organ; but the sensations, thus coexisting, are so very different in themselves, as to be easily distinguishable. When the organ of taste is in a sound state, the application of certain substances produces, immediately, that change or affection of the sensorial organs which is attended with a corresponding change or affection of the sentient mind. In our present state of knowledge, we immediately refer this simple sensation to something which is bitter, or sweet, or acrid, or of some other denomination of sapid quality; and we have no hesitation in classing the sensations as sensations,-effects of laws of action that belong jointly to matter and mind,-not as feelings that arise in the mind from its own independent constitution. But, if we attend sufficiently to the feeling that arises in the case of taste, we shall find, however immediate the reference to a sapid body may seem to be, that it is truly successive to the simple sensation, and is the mere suggestion of former experience, when a body previously recognised by us as an external substance, was applied to our organ of taste ;-in the same manner as, when we see ashes and dying embers, we immediately infer some previous combustion, which we could not have inferred if combustion itself had been a phenomenon altogether unknown to us. In the simple sensation which precedes the reference,-the mere pleasure of sweet ness or the mere pain of bitterness-there is nothing which seems to mark more distinctly the presence of honey or wormwood, or any similar external substance, than in any of our joys or sorrows, to which we have not given a name; and there can be no doubt, that, if the particular feeling which we now term joy, and the particular feeling which we now term sorrow, had been excited, whenever we knew, from other sources, that certain bodies were applied to the tongue, we should have considered these internal feelings as sensations, in the strict sense of the word, precisely in the same manner as we now regard, as sensations, the feeling which we term sweetness, and the feeling which we term bitterness, because, like these sensations, they could not have failed to suggest to us, by the common influence of association, the presence and direct coincidence of the object without. In the case of taste, therefore, as in the case of smell, we could not, from the simple sensations,-if these alone had been given to us, have derived any knowledge of an external world, of substances extended and resisting; but we consider them as sensations, in the strict philosophic meaning of the term, because we have previously acquired our belief of an external world. It may be remarked of these two classes of sensations, now considered, that they have a greater mutual resemblance than our sensations of any other kind. It is only a blind man who thinks, that what is called scarlet is like the sound of a trumpet; but there are tastes which we consider as like smells, in the same manner as we consider them to be like other tastes; and if we had not acquired a distinct knowledge of the seats of our different organs, and had yet known that smells and tastes arose from external causes acting upon some one or other of these, we should probably have been greatly puzzled, in many cases, in our attempt to refer the particular sensation to its particular organ. In considering the advantages which we derive from our organs of smell and taste, the mere pleasures which they directly afford, as a part of the general happiness of life, are to be regarded, from their frequent occurrence, as of no inconsiderable amount. The fragrance of the fields enters largely into that obscure but delightful group of images, which rise in our minds on the mere names of spring, summer, the country, and seems to represent the very form of ethereal purity, as if it were the breath of heaven itself. If we imagine all the innumerable flowers which nature pours out, like a tribute of incense to the God who is adorning her, again to be stripped, in a single moment, of their odour, though they were to retain all their bright diversities of colouring, it would seem as if they were deprived of a spirit which animates them,-how cold and dead would they instantly become,and how much should we lose of that vernal joy, which renders the season of blossoms almost a new life to ourselves. "In vain the golden Morn aloft Waves her dew-bespangled wing; Till April starts, and calls around The sleeping fragrance from the ground."* It is by this delightful quality that the tribes of vegetable life seem to hold a sort of social and spiritual communion with us. It is, as it were, the voice Gray or the Pleasure arising from Vicissitude, Stanza I.-In v. i. the original has, instead of "in vain,” “now.” with which they address us, and a voice which speaks only of happiness. To him who walks among the flowers which he has tended, "Each odoriferous leaf, Each opening blossom, freely breathes abroad The pleasures of the sense of taste, in the moderate enjoyment of which there is nothing reprehensible, are, in a peculiar manner, associated with family happiness. To have met frequently at the same board is no small part of many of the delightful remembrances of friendship; and to meet again at the same board, after years of absence, is a pleasure that almost makes atonement for the long and dreary interval between. In some half civilized countries, in which the influence of simple feelings of this kind is at once more forcible in itself, and less obscured in the confusion of ever varying frivolities and passions, this hospitable bond forms, as you well know, one of the strongest ties of mutual obligation, sufficient often to check the impetuosity of vindictive passions which no other remembrance could, in the moment of fury, restrain. Had there been no pleasure attached to a repast, independent of the mere relief from the pain of hunger, the coarse and equal food would probably have been taken by each individual apart, and might even, like our other animal necessities, have been associated with feelings which would have rendered solitude a duty of external decorum. It would not be easy, even for those who have been accustomed to trace à simple cause through all its remotest operations, to say, how much of happiness, and how much even of the warm tenderness of virtue, would be destroyed by the change of manners, which should simply put an end to the social meal; that meal which now calls all the members of a family to suspend their cares for a while, and to enjoy that cheerfulness which is best reflected from others, and which can be permanent only when it is so reflected, from soul to soul, and from eye to eye. One very important advantage, more directly obvious than this, and of a kind which every one may be disposed more readily to admit, is afforded by our senses of smell and taste, in guiding our selection of the substances which we take as alimentary. To the other animals, whose senses of this order are so much quicker, and whose instincts, in accommodation to their want of general language, and consequent difficulty of acquiring knowledge by mutual communication, are providentially allotted to them, in a degree, and of a kind, far surpassing the instincts of the slow but noble reflector man, these senses seem to furnish immediate instruction as to the substances proper for nourishment, to the exclusion of those which would be noxious. To man, however, who is under the guardianship of affections more beneficial to him than any instinct of his own could be, there is no reason to believe that they do this primarily, and of themselves, though, in the state in which he is brought up, instructed with respect to every thing noxious or salutary, by those who watch constantly over him in the early period of his life, and having, therefore, no necessity to appeal to the mere discrimination of his own independent organs, and, still more, as in the artificial state of things, in which he lives, his senses are at once perplexed and palled, by the variety and confusion of luxurious preparation, it is not easy to say how far his primary instincts, if it had not been the high and inevitable dignity of his nature to rise above these,-might, of themselves, have operated as directors. But, |