Old-Fashioned Ethics and Common-Sense Metaphysics / With Some of Their Applications

by William Thomas Thornton

The doctrine of Hume's which next confronts us is his famous one concerning Cause and Effect. He commences it by explaining that all objects of human enquiry are divisible into two kinds—1. Relations of Ideas, like those of which geometry, algebra, and arithmetic treat, and which are either intuitively certain, or 'discoverable by the mere operation of thought, without dependence on what is anywhere existent in the universe,' as, for example, the truths demonstrated by Euclid, which would be equally incontestable even 'though there were never a circle or a triangle in nature:' 2. Matters of Fact, as, for example, the sun's rising and setting, or the emission of light and heat by fire, which are never discoverable by unassisted reason, because of no one of them would the opposite imply a contradiction or be consequently inconceivable; and in our knowledge of any one of which we can never 'go beyond the evidence of our memory and senses,' except by means of reasons derived from experience of some fact or facts connected in some way or other with the particular matter of fact we are considering.

So far, all is comparatively plain sailing, but Hume now propounds a difficulty which he at first presents as seemingly insurmountable, but which I cannot help thinking to be mainly of his own creation, and which he himself, almost immediately afterwards, suggests a mode, though a very inadequate mode, of overcoming. His language here is not marked by his usual perspicuity, or rather—to speak without respect of persons—it contradicts itself in most astounding fashion; but his meaning is not the less certainly the following, for there is no other construction which his words will bear.

'What,' he asks, 'is the foundation of all conclusions from experience?' Why is it that, having found that such an object has always been attended with such an effect, we infer that similar objects will always be attended with similar effects? The proposition that a certain antecedent has always been followed by a certain consequent, and the proposition that the same antecedent will be followed by the same consequent, are not identical. What, then, is the connexion between them which causes one to be inferred from the other? The connexion is unhesitatingly pronounced by him to be neither intuitively perceived, nor yet to be 'founded on any process of the understanding.' If you insist that the inference is made by a chain of reasoning, he challenges you to produce that reasoning, and taking for granted that you have none to produce, he proceeds to indicate what principle it is which, in his opinion, does determine us to form the inference. That principle he declares to be custom or habit, by which alone, he asserts, we are, after the constant conjunction of two objects, determined to expect the one from the appearance of the other; adding that all inferences from experience are effects of custom, not of reasoning.

What is the correct answer to this question of Hume's I shall be rash enough to endeavour to indicate a little further on; meanwhile there can be no temerity in saying that whatever be the right answer, Hume's is certainly a wrong one. Habit plainly cannot be its own parent. It enables us to repeat more easily what we have already repeatedly done, but it cannot be the cause of our doing or being able to do anything for the first time. An infant that has once burnt its fingers by touching the flame of a candle, expects that if it touch the flame again it will burn its fingers again, but it does not expect this because it has been in the habit of expecting it. Neither, if we be here bidden to understand that the habit referred to is not any mental habit of our own, but a habit which we have observed certain phenomena to have of following each other, shall we thereby be brought one whit nearer the truth. Our infant with the burnt finger has not observed that flame is in the habit of burning. It only knows that flame did burn on the one occasion on which it tried the experiment, which experiment it consequently declines to repeat. Besides, no one needs to be told that inferences, though thus capable of being drawn from single occurrences, are drawn with increased confidence from observation of habit. We all know already that, having always found that fire burns, we infer that it always will burn. What we want to know is, why we draw this inference. This is the question which Hume puts, and respecting which he gives very positively the negative reply that the inference is not drawn either intuitively, nor yet by any process of the understanding. Yet that a body when not moving must needs be at rest, is not more certainly demonstrable than that inferences cannot possibly be drawn except in one or other of these two ways. Is not every inference a species of belief, and must not every belief be either innate within us, or have been acquired artificially; and, as in the latter case, it is a mental acquisition, must it not in that case have been acquired by an operation of the mind or understanding? Is it not clear, then, that inferences must always be either intuitive or ratiocinative; and is it not strange that Hume should deny that they ever are so? Yet stranger still is it, that even while denying them to be either one or the other, he, almost in the same breath, pronounces them to be both. For, after having on one page denied that they are founded on reason, or any process of the understanding, he describes them on the next page as being not simply founded on, but as being themselves 'processes of the mind,' 'processes of thought,' and immediately afterwards 'arguments,' nay, 'reasonings from experience;' and, yet again, after as short a pause, these very same 'reasonings,' and 'arguments,' and 'processes of the mind and thought,' he concludes by styling 'natural instincts which no reason or process of the thought or understanding is able either to produce or to prevent'—'operations of the soul as unavoidable' when the mind is placed in certain circumstances, as it is 'to feel the passion of love when we receive benefits, or hatred when we meet with injuries.'

What are we to say to a description of mental operations which are and are not 'arguments' and 'reasonings,' which are and are not 'processes of thought,' which are not 'intuitive,' and which yet are 'instincts?' How are we to account for such amazing inconsistencies in an exposition of one of the greatest of philosophers? With all humility, I submit the following as a possible solution of the enigma.

The one solitary ground on which Hume denies the argumentative and ratiocinative character of what he nevertheless terms arguments and reasonings, is the impossibility of producing the chains of argument or reasoning of which they are composed. But this impossibility can at most only prove that the reasonings are elementary, and have, consequently, no component parts into which they can be resolved. But reasoning is not the less reasoning for being elementary, or for being only a single link in a chain, instead of being itself a chain composed of many links. Still, being elementary, it may occur to, and pass through, the mind with extreme rapidity—with not less rapidity than an intuition or instinct, for which therefore it may easily be mistaken, as accordingly it has actually been by Hume. But that a reasoning from experience is not really an instinct is certain, firstly, because intuitive or instinctive reasoning, if not a phrase absolutely devoid of meaning, is a contradiction in terms; and, secondly, because, if it were instinctive, it would precede instead of following experience, and a baby, instead of finding out that flame burns by touching it, would know beforehand that flame burns, and would therefore not touch it.

From the species of Belief constituted by an inference from experience, Hume, by an easy transition, passes on to Belief in general, which he defines to be 'nothing but a more vivid, lively, forcible, firm, steady conception of an object, than what the imagination alone is ever able to attain,' referring, by way of illustration, to an animal with the head of a man and the body of a horse, which anyone can imagine, but no one can believe in, and desiring us apparently to suppose that if our groom were to come and tell us that he had found a centaur feeding in the paddock beside our favourite saddle-horse, our sole reason for believing in the horse and for not believing in the centaur would be our greater ability to conceive the one than the other. That such a definition should for a moment have satisfied its author's curiosity, is itself a psychological curiosity which must not, however, be suffered to detain us. Whoever, not content with knowing perfectly well what belief is, desires to have his knowledge of it set down in writing, should read the admirable notes on the subject, with which Mr. John Mill and Mr. Bain have enriched the last edition of Mr. James Mill's 'Analysis of the Human Mind.' Most readers, however, will probably be disposed to avail themselves here of a rather favourite phrase of Hume himself, and to plead that, 'if we agree about the thing, it is needless to dispute about terms;' and it is not unlikely that such of them as may have formed their notion of metaphysical discussions in general from the specimens given above, may go so far as to hint a doubt whether any of the nice verbal distinctions which metaphysicians so much affect, are really worth the trouble required to understand them. Nor would anyone, perhaps, be much the worse for acting upon this suspicion, provided that, in accordance with it, he kept altogether aloof from the studies which it disparages. His ideas need not be the less clear because he neither knows nor cares of what they are copies, nor whether they are copies of anything; nor will the order of their occurrence be at all affected in consequence of his being similarly careless, whether that order is or is not governed by a law of association; neither need his inferences from experience be the less sound in consequence of his never having enquired how or why they are deduced. But although the most absolute ignorance and corresponding indifference about these and kindred topics may not tend in the least to disqualify him for performance of the whole duty of man, it is not the less important that, if he do care to know aught about them, his knowledge should be exact, for there is no knowing beforehand how luxuriantly the minutest germ of theoretical error may ramify in practice, or into what substantive quagmire trust in deceitful shadows may lead. These respectable aphorisms may be beneficially borne in mind during perusal of what is about to be said.

If the fact were really, as Hume supposed, that we have no reason for our inferences from experience, and draw them only because either we have been in the habit of drawing them, or because we are so constituted as to be unable to help drawing them, the reason of our drawing them plainly could not be that we perceive any necessary connection between antecedent and consequent events, or any force or power binding these together as cause and effect. Accordingly, Hume does not scruple to affirm that 'we have no idea of connection or power at all, and that these words are absolutely without meaning when employed either in philosophical reasoning or in common life.' Every idea, he argues, referring to a rule which he somewhat hastily supposes himself to have already proved to be without exception, must needs have been copied from some preceding sensible impression, but neither from within nor from without can we have received an impression from which this particular idea can have been copied. No keenest scrutiny of any portion of matter, no study of its external configuration or internal structure could, previously to experience, enable us to conjecture that it could produce any effect whatever, still less any particular effect: could enable us to guess, for instance, that flame would burn, or ice would chill, if touched. Nor even though on once touching flame we get our fingers burnt, are mature philosophers like us to conclude, as if we had no more intelligence than so many babies, that if we touch again we shall be burnt again. All we have as yet learnt from the experiment is that the sensation of touching fire has once been followed by the sensation of burning, but nothing has occurred to suggest that in the first sensation lurked any secret power of producing the second. And what a single experiment does not prove, no number of repetitions of precisely the same experiment with precisely the same results can prove. Even though on a lengthened course of experience we have found that in every case of our touching flame our fingers have been burnt, we are still as far as ever from perceiving any bond of connection between the two events. We do indeed believe that as flame when touched has hitherto invariably burnt, so, whenever touched hereafter, it will hereafter invariably burn; but this, according to Hume, we believe simply because by long practice we have contracted such a habit of associating the idea of touched flame with burnt fingers, that whenever we witness the one we cannot help expecting the other.

Neither, if, withdrawing our eyes from the outward world, we cast them inwardly upon the operations of our own minds, shall we, according to Hume, any the more discover what we are in search of. What though we know by experience that whatever, within certain limits, our will appoints, our bodily organs or mental faculties will ordinarily perform; that our limbs will move as we wish them, and our memory, reason, or imagination bring forward ideas which we desire to contemplate, what knowledge have we here beyond that of certain volitions and certain other acts taking place in succession? What smallest evidence have we of any connection between the volitions and the other acts? A volition is an operation of the mind, is it not? and body is matter, is it not? And do you pretend to know—can you form the smallest approach to a guess—how mind is united with body, and how it is possible therefore for the refined spiritual essence to actuate the gross material substance. If you 'were empowered by a secret wish to remove mountains or to control the planets in their orbit,' would such extensive authority be one whit more inexplicable than the supposed ability of your will to raise your hand to your head or to cause your foot to make one forward step?

If, nevertheless, you fancy you understand in what manner the will has some of the bodily organs under its government, how, pray, do you account for its not having all equally—the heart and liver as well as the tongue and fingers? Without trying, you never would have discovered that your bowels will not, any more than without trying you could have known that your limbs will, ordinarily move in conformity with your wishes. Neither, if one of your limbs were to be suddenly paralysed, would you, until you tried, become aware that it would no longer move as you wished. If there be, then, a power attached to the will, it is plainly experience alone which apprises you of its existence; whereas if you were independently conscious of it, you would know beforehand precisely what it can and what it cannot effect, and would, moreover, when you lost it, become instantly aware of your loss.