“That the intelligence of any being,” to use the words of D'Alembert, “should not pass beyond certain limits—that, in one species of beings, it should be more or less circumscribed, than in another—all this is not surprising, more than that a blade of grass should be less tall than a shrub; or a shrub than an oak. But that the same being should be at once arrested by the narrow circle which nature has traced around him, and yet constantly reminded, that, beyond these limits, there are objects which he is never to attain—that he should be able to reason, till he loses himself, on the existence and nature of these objects, though condemned to be eternally ignorant of them—that he should have too little sagacity to resolve an infinity of questions, which he has yet sagacity enough to make—that the principle within us, which thinks, should ask itself in vain, what it is which constitutes its thought, and that this thought, which sees so many things, so distant, should yet not be able to see itself, which is so near,—that self, which it is notwithstanding always striving to see and to know—these are contradictions, which, even in the very pride of our reasoning, cannot fail to surprise and confound us.”

All that remains for us, in that impossibility which nature has imposed on us of attaining a more intimate knowledge of the essence and constitution either of mind or of matter, is to attend to the phenomena which they present, analysing whatever is complex, and tracing the order of every sequence. By attentive reflection on the phenomena themselves, and on all the circumstances which precede or follow them, we shall be able to discover the relations which they mutually bear, and to distinguish their casual coincidence, or succession, from those invariable relations which nature has established among them as causes and effects. This, humble as it may seem, is, as I have said, the true philosophy of man; because it is all of which man is capable. To inquire, as may be thought, more deeply into the essences of things, or the nature of certain supposed bonds by which they are connected, is to show, not that we have advanced far in the progress of science, but that we have gone far astray; not that we know more than philosophers of humbler views and pretensions, but that we know less; since it proves that we are unacquainted with the limits within which nature has bounded our prospect, and have not attained that prime knowledge, which consists in knowing how little can be known.

If the philosophy, not of mind only, but of the universe, is to be found, as Hobbes has boldly said, within ourselves,—in the same manner as the perfect statue is to be found in the rude block of the quarry, when all the superfluous mass, that adheres to it, has been removed,—in no respect can it more justly be said to be in our own minds than in this, that it is only by knowing the true extent, and consequently the limits, of our intellectual powers, that we can form any rational system of philosophic investigation. Then, indeed, Philosophy may be truly said, in his strong figurative language, to be Human Reason herself, hovering over all created things, and proclaiming their order, their causes, and effects. “Philosophiam noli credere eam esse, per quam fiunt lapides philosophici, neque illam quam ostentant codices metaphysici; sed Rationem Humanum naturalem per omnes res creatas sedulo volitantem, et de earum ordine, causis, et effectibus, ea quæ vera sunt renuntiantem. Mentis ergo tuæ, et totius mundi filia philosophia in te ipso est; nondum fortasse figurata, sed genitori mundo qualis erat in principio informi similes. Faciendum ergo tibi est quod faciunt statuarii, qui materiam exculpentes supervacraeum, imaginem non faciunt sed inveniunt.”[42]

After these remarks on physical inquiry in general, and its particular application to our own science, I trust that we shall now proceed to observe, and analyse, and arrange the mental phenomena, with clearer views, both of the materials on which we have to operate, and of the nature of the operations which we have to perform. We may consider the mind as now lying open before us, presenting to us all its phenomena, but presenting them in assemblages, which it is to be our labour to separate and arrange. In this separation and arrangement, there are difficulties, I confess, of no slight kind. But, I trust, that you have the spirit, which delights in overcoming difficulties, and which, even if its most strenuous exertions should fail, delights in the very strenuousness of the endeavour. In what admits our analysis, and in what transcends it, we shall always find much that is truly wonderful in itself, and deserving of our profoundest admiration; and, even in the obscurest parts of the great field of mind, though we may see only dimly, and must, therefore, be cautious in inquiring, and fearful of pronouncing, we may yet, perhaps, be opening paths that are to lead to discovery, and, in the very darkness of our search, may perceive some gleams of that light, which, though now only dawning upon us, is to brighten on the inquirers of other ages.

In proceeding to examine and compare the mental phenomena, the first circumstance that strikes us, prior to any attempt to arrange them in classes, is, that the mind which exhibits these is susceptible of a variety of feelings, every new feeling being a change of its state; and, indeed, it is by such changes alone that it manifests itself, either in our own consciousness, or in the actions of our fellow men. If it could exist only in one everlasting state,—such as now constitutes the feeling of any particular moment,—it is quite superfluous to say, that it could not reason upon this state,—for this very reasoning would itself imply the change, which is supposed to be impossible; and as little could this one unchanged and unchangeable feeling be an object of reasoning to others, even if there were any mode of its becoming manifest to them, which there evidently could not be. It is, perhaps, even not too extravagant an assertion of Hobbes, who supposes a mind so constituted as to perceive only one colour, and to perceive this constantly, and affirms, that, in that case, it would be absurd to say that it had any perception at all, being rather, as he expresses it, stupified than seeing. “Attonitum esse et fortasse aspectare eum, sed stupentem dicerem, videre non dicerem; adeo sentire semper idem, et non sentire ad idem recidunt.”

Mind, then, is capable of existing in various states; an enumeration of the leading classes of which, as I before remarked, is all that constitutes our definition of it. It is that, we say, which perceives, remembers, compares, grieves, rejoices, loves, hates; and though the terms, whatever they may be, that are used by us, in any such enumeration, may be few, we must not forget that the terms are mere inventions of our own for the purpose of classification, and, that each of them comprehends a variety of feelings, that are as truly different from each other, as the classes themselves are different. Perception is but a single word; yet, when we consider the number of objects that may act upon our organs of sense, and the number of ways in which their action, may be combined, so as to produce one compound effect, different from that which the same objects would produce separately, or in other forms of combination, how many are the feelings which this single word denotes!—so many, indeed, that no arithmetical computation is sufficient to measure their infinity.

Amid all this variety of feelings, with whatever rapidity the changes may succeed each other, and however opposite they may seem, we have still the most undoubting belief, that it is the same individual mind, which is thus affected in various ways. The pleasure, which is felt at one moment, has indeed little apparent relation to the pain that was perhaps felt a few moments before; and the knowledge of a subject, which we possess, after having reflected on it fully, has equally little resemblance to our state of doubt when we began to inquire, or the total ignorance and indifference which preceded the first doubt that we felt. It is the same individual mind, however, which, in all these instances, is pleased and pained, is ignorant, doubts, reflects, knows. There is something “changed in all, and yet in all the same,” which at once constitutes the thoughts and emotions of the hour, and yet outlives them,—something, which, from the temporary agitations of passion, rises, unaltered and everlasting, like the pyramid, that lifts still the same point to heaven, amid the sands and whirlwinds of the desert.

The consideration of the mind, as one substance, capable of existing in a variety of states, according as it is variously affected, and constituting, in these different states, all the complex phenomena of thought and feeling, necessarily involves the consideration of consciousness, and of personal identity. To the examination of these, accordingly, I now proceed, as essential to all the inquiries and speculations, in which we are afterwards to be engaged; since, whatever powers or susceptibilities we may consider as attributes of the mind, this consideration must always suppose the existence of certain phenomena, of which we are conscious, and the identity of the sentient or thinking principle, in which that consciousness resides, and to which all the varieties of those ever-changing feelings, which form the subjects of our inquiry, are collectively to be referred.

Our first inquiry, then, is into the nature of

CONSCIOUSNESS.