Lectures on the Philosophy of the Human Mind (Vol. 1 of 3). Brown Thomas
over nature, which He, who is its only real Sovereign, has designed, in the magnificence of His bounty, to confer on us, together with the still greater privilege of knowing that Omnipotence to which all our delegated empire is so humbly subordinate. It is a command which can be exercised by us, only as beings, who, according to one of the definitions that have been given of man, look both before and behind; or, in the words of Cicero, who join and connect the future with the present, seeing things, not in their progress merely, but in the circumstances that precede them, and the circumstances that follow them, and being thus enabled to provide and arrange whatever is necessary for that life, of which the whole course lies open before us. “Homo autem (quod rationis est particeps, per quam consequentia cernit, causas rerum videt, earumque progressus et quasi antecessiones non ignorat, similitudines comparat, et rebus præsentibus adjungit atque annectit futuras) facile totius vitæ cursum videt, ad eamque degendam præparat res necessarias.”28
That power is nothing more than the relation of one object or event as antecedent to another object or event, though its immediate and invariable consequent, may, perhaps, from the influence of former habits of thought, or rather, of former abuse of language, at first appear to you an unwarrantable simplification; for, though you may never have clearly conceived, in power, any thing more than the immediate sequence of a certain change or event, as its uniform attendant, the mere habit of attaching to it many phrases of mystery, may, very naturally, lead you to conceive, that, in itself, independently of these phrases, there must be something peculiarly mysterious. But the longer you attend to the notion, the more clearly will you perceive, that all which you have ever understood in it, is the immediate sequence of some change with the certainty of the future recurrence of this effect, as often as the antecedent itself may recur in similar circumstances. To take an example, which I have already repeatedly employed, when a spark falls upon gunpowder, and kindles it into explosion, every one ascribes to the spark the power of kindling the inflammable mass. But let any one ask himself, what it is which he means by the term, and, without contenting himself with a few phrases that signify nothing, reflect, before he give his answer, and he will find, that he means nothing more than that, in all similar circumstances, the explosion of gunpowder will be the immediate and uniform consequence of the application of a spark. To take an example more immediately connected with our own science, we all know, that as soon as any one, in the usual circumstances of health and freedom, wills to move his arm, the motion of his arm follows; and we all believe, that, in the same circumstance of health, and in the same freedom from external restraint, the same will to move the arm, will be constantly followed by the same motion. If we knew and believed nothing more, than that this motion of the arm would uniformly follow the will to move it, would our knowledge of this particular phenomenon be less perfect, than at present, and should we learn any thing new, by being told, that the will would not merely be invariably followed by the motion of the arm, but that the will would also have the power of moving the arm; or would not the power of moving the arm be precisely the same thing, as the invariable sequence of the motion of the arm, when the will was immediately antecedent?
This test of identity, as I have said in my Essay on the subject, appears to me to be a most accurate one. When a proposition is true, and yet communicates no additional information, it must be of exactly the same import, as some other proposition, formerly understood and admitted. Let us suppose ourselves, then, to know all the antecedents and consequents in nature, and to believe, not merely that they have once or repeatedly existed in succession, but that they have uniformly done so, and will continue forever to recur in similar series, so that, but for the intervention of the Divine will, which would be itself, in that case, a new antecedent, it will be absolutely impossible for any one of the antecedents to exist again, in similar circumstances, without being instantly followed by its original consequent. If an effect be something more than what invariably follows a particular antecedent, we might, on the present supposition, know every invariable consequent of every antecedent, so as to be able to predict, in their minutest circumstance, what events would forever follow every other event, and yet have no conception of power or causation. We might know, that the flame of a candle, if we hold our hand over it, would be instantly followed by pain and burning of the hand, – that, if we ate or drank a certain quantity, our hunger and thirst would cease: – we might even build houses for shelter, sow and plant for sustenance, form legislative enactments for the prevention or punishment of vice, and bestow rewards for the encouragement of virtue; – in short, we might do, as individuals and citizens, whatever we do at this moment, and with exactly the same views, and yet, (on the supposition that power is something different from that invariable antecedence which alone we are supposed to know,) we might with all this unerring knowledge of the future, and undoubting confidence in the results which it was to present, have no knowledge of a single power in nature, or of a single cause or effect. To him who had previously kindled a fire, and placed on it a vessel full of water, with the certainty that the water, in that situation, would speedily become hot, what additional information would be given, by telling him that the fire had the power of boiling water, that it was the cause of the boiling, and the boiling its effect? And, if no additional information would in this case be given, then, according to the test of this identity of propositions, before stated, to know events as invariably antecedent and consequent, is to know them as causes and effects; and to know all the powers of every substance therefore, would be only to know what changes or events would, in all possible circumstances, ensue, when preceded by certain other changes or events. It is only by confounding casual with uniform and invariable antecedence, that power can be conceived, to be something different from antecedence. It certainly is something very different from the priority of a single moment; but it is impossible to form any conception of it whatever, except merely as that which is constantly followed by a certain effect.
Such is the simple, and, as it appears to me, the only intelligible view of power, as discoverable in the successive phenomena of nature. And yet, how different from this simple view is the common, or, I may almost say, the universal notion of the agencies, which are supposed to be concerned in the phenomena that are the objects of philosophic inquiry. It is the detection of the powers of nature, to which such inquiry is supposed to lead, – but not of powers, in the sense in which alone that phrase is intelligible, as signifying the objects themselves which uniformly precede certain changes. The powers which our investigation is to detect, or which, at least, in all the phenomena that come under our observation, we are to consider as the sole efficient, though invisible producers of them, are conceived by us to be something far more mysterious, – something that is no part of the antecedent, and yet is a part of it, – or that intervenes between each antecedent and consequent, without being itself any thing intermediate, – as if it were possible that any thing could intervene in a series, without instantly becoming itself a part of the series, – a new link in the lengthened chain, – the consequent of the former antecedent, and the antecedent of the former consequent.
To me, indeed, it appears so very obvious a truth, that the substances which exist in nature – the world, its living inhabitants, and the adorable Being who created them, – are all the real existences in nature, and that, in the various changes which occur, therefore, there can as little be any powers or susceptibilities different from the antecedents and consequents themselves, as there can be forms different from the co-existing particles which constitute them, – that to labour thus to impress this truth upon your minds, seems to me almost like an attempt to demonstrate a self-evident proposition. An illusion, however, so universal, as that which supposes the powers of nature, to be something more, than the mere series of antecedents themselves, is not rashly, or without very full inquiry, to be considered as an illusion; and, at any rate, in the case of a mistake, so prevalent and so important in its consequences, it cannot be uninteresting, to inquire into the circumstances, that appear most probably to have led to it. Indeed the more false, and the more obviously false the illusion is, the more must it deserve our inquiry, what those circumstances have been which have so long obtained for it the assent, not of common understanding merely, but of the quick-sighted and the subtile. For a full view of my opinions on this subject, I must refer you to the work which I have published on the Relation of Cause and Effect; and the short abstract of them which I now offer, as it would be superfluous for those who have read and understood that work, is chiefly for the sake
Cicero de Officiis, lib. i. c. 4.