Pirates & Revolutionaries: Hume, A Treatise of Human Nature, Book 1, Part 3, Sect 8 Of the Causes of Belief §§228-244

by Corry Shores
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[The following is summary, up to the end where I reproduce this section in full. My commentary is in brackets. Paragraph headings are my own.]

David Hume

A Treatise of Human Nature

Book I: Of the Understanding

Part III: Of Knowledge and Probability

Section VIII: Of the Causes of Belief

§228 We Will Examine Belief's Causes

Previously Hume explained the nature of belief. He showed that it consists in a lively idea related to a present impression. Now he will examine the principles that found belief and the source of believed idea's vivacity.

§229 Life Begets Life

Hume presents the following as a general maxim of human nature:

1) impressions become present to us.

2) when they do, these impressions

2a) transport the mind to related ideas, but as well, these impressions

2b) communicate their force and vivacity. (98c)

Our disposition determines much of the way that our mind operates. Our spirits might be more-or-less elevated. And out attention might be more-or-less fixed. When these factors are greater, our mind will apply itself with greater action. As a result, the object conceived will more elevate and enliven our thought. And every action of our minds will be stronger and more vivid. (98d)

These levels of mental activity depend on our disposition. But our disposition depends on how engaging we find our objects of attention. New objects will give "a new direction to the spirits" and thereby change our disposition. But consider instead when our mind fixes on the same object or when it "passes easily and insensibly along related objects." In this case the same disposition maintains for a longer duration.

Now consider when our mind is enlivened by a present vivid impression. We know already that it will call to mind related ideas. This happens regardless of the idea's vivacity. But in these cases of vived impressions, our minds form a more lively idea of the related objects.

The change of the objects is so easy, that the mind is scarce sensible of it, but applies itself to the conception of the related idea with all the force and vivacity itacquir'd from the present impression. (99b)

§230 Picture a Picture

It is possible that we might understand the reality of this transition merely by thinking about its nature and essence. Hume, however, prefers to use experience.

He first has us imagine that someone shows us a picture of a friend who is currently somewhere else. By seeing his imagine, our idea of him is vivified.

upon the appearance of the picture of an absent friend, our idea of him is evidently inliven'd by the resemblance, and that every passion, which that idea occasions, whether of joy or sorrow, acquires new force and vigour. (99b, emphasis mine)

We have a present impression of the picture we see. But there is also a relation to the vivified idea of our friend. Now, if the picture did not capture well his appearance, then it might not evoke our thoughts of him. Consider further if both our friend and his picture were absent. Then, we imagine first his picture, which would evoke our idea of him. But now our idea for him is weakened even more.

We take a pleasure in viewing the picture of a friend, when 'tis set before us; but when 'tis remov'd, rather choose to consider him directly, than by reflexion in an image, which is equally distinct and obscure. (99d)

§231 Vivacious Catholic Beliefs

Hume now has us imagine Roman Catholic ceremonies. Catholics undergo elaborate rituals to enliven their beliefs.

The devotees of that strange superstition usually plead in excuse of the mummeries, with which they are upbraided, that they feel the good effect of those external motions, and postures, and actions, in enlivening their devotion, and quickening their fervour, which otherwise would decay away, if directed entirely to distant and immaterial objects. (99-100)

Catholics represent objects of their faith. They render them into sensible images. This makes the faith-objects more present to their minds. For if they only contemplated them intellectually, they would conceive the objects less vivaciously.

Sensible objects have always a greater influence on the fancy than any other; and this influence they readily convey to those ideas, to which they are related, and which they resemble. (100b)

This example provides an 'expedient.' It demonstrates the principle that sensible resemblances enliven their ideas. This happens all the time in our lives. So we all have many such 'experiments.'

§232 Homecoming Impressions

So impressions may resemble their idea. The greater the resemblance, the more the idea's vivacity.

To explain now the role of contiguity, Hume has us imagine that we are traveling on our way home. When we are still quite far from home, we will see things in that region. They are at least on the way home. So they might evoke faint perceptions of our destination. As we draw nearer to home, we will see other things in our more neighboring regions. They are more familiar to us. And we have come more to associate them with our idea of home. Because they are more contiguous to our home, they evoke the idea of home with greater ease and vivacity.

Hence such examples supply even more 'experiments' that we experience in everyday life.

§233 Causing Saintly Beliefs

So with greater resemblance and contiguity comes increased vivacity in associated ideas. To explain how causal relations operate similarly, Hume has us imagine superstitious people. They like relics of saints and holy men. Like the Catholic images and rituals, these relics enliven their devotion by evoking a stronger sense of the saintly life they wish to lead.

We saw previously the importance of causal chains. So imagine we had the relic of the saint's handiwork, like a piece of the clothes she made for herself. She original affected these objects. Then they were passed down through the generations. If we looked at their work, we can learn a lot from them. It is not direct knowledge. But it would be more mediated if we learned it from a book. For the historians writing the book either learned some things about the saint from such remnants, or they learned these things from other historians who examined the remnants. But when we have their handiwork ourselves, we may learn about them more directly, even though they are still indirect "imperfect effects." For these relics are "connected with him by a shorter chain of consequences than any of those, from which we learn the reality of his existence." (101b)

This phaenomenon clearly proves, that a present impression with a relation of causation may, inliven any idea, and consequently produce belief or assent, according to the precedent definition of it. (101b)

§234 We May Conclude by Reason that Beliefs Involve Causal Transitions to Vivified Ideas

In order to show our progress, Hume enumerates what we now know for certain:

1) There are matters of fact. We have ideas of them, and we believe those ideas.

2) These ideas that we believe arise only from a relation to a present impression.

3) Our beliefs do not add anything to the idea. They only change our manner of conceiving the idea by making it stronger and more lively.

We also know that causes and effects are related by resemblance, contiguity, and constant connection [for more see §216.] And we just saw in our experiments that the stronger the relation of resemblance or contiguity, the more vivid the impression and the greater our belief.

So we see that in these cases of causal inferences, we have evidence that our present impressions may enliven our ideas by bringing about a relation or transition in our fancy.

There enters nothing into this operation of the mind but a present impression, a lively idea, and a relation or association in the fancy betwixt the impression and idea. (101d)

§235 Whence Belief?

So we may be rationally certain that beliefs involve causal transitions to enlivened ideas. But Hume would like also to provide empirical evidence.

Let's imagine someone presents a rose to us. We form the conclusion that the rose would make a wonderful gift.

We assent to that idea. Thus we believe it.

So we have the impression of the flower, and the idea of its fitness to become a gift.

Now there are certain associative relations between our impressions of roses and our ideas of gifts. The rose's beauty, for example, tells us that it would make a great gift, because beautiful things make for nice gifts. So when we see the beautiful rose, that impression evokes the notion of giving it as a gift. And, we have a belief regarding this conclusion.

So there are certain powers and qualities of the impressions' and ideas' relations. These relations are the causal ones. By means of them, impressions evoke ideas.

But it is not by means of these same relations that impressions influence our beliefs, Hume claims. Rather, the impressions have some other qualities that produce our beliefs, which we will now examine. [consult the original text; a better interpretation is possible: "I suppose there is an object presented, from which I draw a certain conclusion, and form to myself ideas, which I am said to believe or assent to. Here it is evident, that however that object, which is present to my senses, and that other, whose existence I infer by reasoning, may be thought to influence each other by their particular powers or qualities; yet as the phenomenon of belief, which we at present examine, is merely internal, these powers and qualities, being entirely unknown, can have no hand in producing it. It is the present impression, which is to be considered as the true and real cause of the idea, and of the belief which attends it. We must therefore endeavour to discover by experiments the particular qualities, by which it is enabled to produce so extraordinary an effect."]

§236 Caused Belief

If we only perceive an impression, but do not have an evoked idea (yet), then we do not also yet have a belief. But the impression may found a belief when we experience its causal inference.

We must in every case have observ'd the same impression in past instances, and have found it to be constantly conjoin'd with some other impression. (102bc)

§237 Believing Customary Repetitions

Now consider that when we have a belief, there are no other mental operations involved than inferential evocation. The fact that believed ideas are vivified does not constitute an additional action.

I conclude, that the belief, which attends the present impression, and is produc'd by a number of past impressions and conjunctions; that this belief, I say, arises immediately, without any new operation of the reason or imagination. (102c)

Now, our associative tendencies result from past repetitions. They do not add anything new to our causal inferences. We call them customs.

Hume is certain: all beliefs following from present impressions are derived from customs. (102d)

Now as we call every thing CUSTOM, which proceeds from a past repetition, without any new reasoning or conclusion, we-may establish it as a certain truth, that all the belief, which follows upon any present impression, is deriv'd solely from that origin. When we are accustom'd to see two impressions conjoin'd together, the appearance or idea of the one immediately carries us to the idea of the other. (102-103, emphasis mine)

§238 The Intense Forces of the Vivacious Ideas We Believe

Hume wants cause for his certainty. So he will make another experiment to see if anything except custom is required for producing belief.

[Let's consider a new example. Imagine that you have never seen pictures of the moon's surface. So you do no know it is covered in craters. You then buy a telescope. Someone says, 'you will see how the moon is covered in craters.' Now, we have not yet had a sense-impression of the moon's surface. But we do conceive the idea of it being cratered. So here is a case of an idea without an immediate (or closely mediated) sense impression. We notice two things about this idea:

1) it evokes a very faint indeterminate image in our mind. For we have very little idea what a cratered moon would look like, and

2) we do not believe this idea.

Then, that night we point our telescope to the moon and see in fine detail its cratered surface. How remarkable. We even have vivid dreams that night of us exploring the deep moon pocks. We notice two things now about the idea of the moon's cratered surface:

a) it evokes vivid images in our mind, and

b) we believe it.]

Hume's experiment is he considers an idea without its impression. He notices that there is no belief in it. So present impressions are absolutely necessary for beliefs.

Then Hume compares two things:

1) the idea of something that is not evoked by an impression, which we do not believe, and

2) the idea of something that is evoked by an impression, which we do believe.

He finds that the difference between the believed and not-believed ideas is only the intensity of their force and vivacity.

A present impression, then, is absolutely requisite to this whole operation; and when after this I compare an impression with an idea, and find that their only difference consists in their different degrees of force and vivacity, I conclude upon the whole, that belief is a more vivid and intense conception of an idea, proceeding from its relation to a present impression. (103b, emphasis mine)

§239 Philosophy is Sensitivity

On the basis of this discovery, Hume concludes:

Thus all probable reasoning is nothing but a species of sensation. 'Tis not solely in poetry and music, we must follow our taste and sentiment, but likewise in philosophy. (103bc)

We assent to arguments when their ideas force themselves upon us with more vivacity. Our causal reasoning is no more than an extension of our sensation.

When I am convinc'd of any principle, 'tis only an idea, which strikes more strongly upon me. When I give the preference to one set of arguments above another, I do nothing but decide from my feeling concerning the superiority of their influence. Objects have no discoverable connexion together; nor is it from any other principle but custom operating upon the imagination, that we can draw any inference from the appearance of one to the existence of another. (103c)

§240 Lethal River: Passive Pre-Conscious Associative Inference

Hume will now take note of the more mysterious workings of our mind.

He has us imagine a man on a journey. He encounters a river. He stops. Why? Is it because he calls to his mind all the past experiences he has had with the dangers of rivers, or the stories he has heard about other people's peril in rivers? No, for these past experiences "operate on our mind in such an insensible manner as never to be taken notice of, and may even in some measure be unknown to us." (103d)

The idea of sinking is so closely connected with that of water, and the idea of suffocating with that of sinking, that the mind makes the transition without the assistance of the memory. The custom operates before we have time for reflection. The objects seem so inseparable, that we interpose not a moment’s delay in passing from the one to the other. (104a)

But we may think about water without thereby thinking of suffocation, and vice versa. So the transition from one to the other is the product of our experiences and not from the ideas themselves. We make this inference without realizing it. And we believe what we conclude. Hence,

experience may produce a belief and a judgment of causes and effects by a secret operation, and without being once thought of. (104b)

So we see that the understanding or imagination my draw inferences from past experience without reflecting on it. The man who stopped before the river did not need to form some principle regarding the danger of strong waters and then reason upon this principle in order to conclude that he should not cross the river.

We previously considered the argument that we draw our causal inferences by reasoning upon ideas. This was a sort of active association of ideas. [see §§207 -219.] This position presupposes that new instances must resemble our previous experiences. So according to this theory, for the man to infer that he should not cross, he would have had to himself had faced death in a river.

But here we have counter-evidence. For, we made a causal inference without any active rationalization at all. And the man we presume need not have faced death in a river. He might have come near drowning at sea instead. Such similar but non-resembling past experiences can evoke certain ideas by means of a passive association.

§241 Our Experiences with Making Inferences not Based on Experiences

Now consider one type of causal relation. Examples would be gravity, impulsive force, solidity, or other well-known uniform conjunctions of cause and effect. We may use formulas to make predictions regarding these relations. So we infer effects from causes in these scientific cases without drawing from our past experiences. However, other causal relations are not so uniform and well-established. These are more rare and unusual object-associations. To draw inferences based on them, it might help to recall our past experiences with them.

Now, some will counter-argue Hume's position on the basis of the more uniform relations. For, we can conduct a scientific experiment that isolates variables. We may then uncover causal relations. When seeing those variables again, we may infer the effects from the causes. But notice that in this case we only had one prior experience. And that is not enough to form a habit. So it seems that we have examples of times that we make causal inferences based on our reasoning and not on the customs we developed from past experiences.

Hume points-out a custom involved in these reasonings that is not immediately evident. The only way we will be confident that our experiment can produce reliable predictions, is if we had past experiments that also used the scientific method and produced predictions that recurrently proved accurate. Hence we see again that we cannot make such inferences unless on the grounds of prior experiences.

§242 Retained Vivacity

Hume adds that our common language does not make clean terminological distinctions between the different operations of the mind. Hence it is difficult speaking of them with precision. This has confused Hume. And it might also cause his readers to doubt his thinking.

One of Hume's claims is that opinion or belief is no more than a strong and lively idea derived from a present impression related to it. But perhaps the terms "strong" and "lively" are unclear in this application, which might provoke our objections.

Consider we now form an idea. But we forgot the corresponding impression. But we know some impression must have caused it. So we conclude that this impression must have existed. And, we believe this conclusion, which means there must be some force and vivacity to the idea. But if there is no sense impression present, then where does the force and vivacity come-from?

Hume answers that the idea itself now serves in place of the impression, and functions in the same way. For, ideas are like impressions: both are perceptions of the mind. The idea was caused by an impression. That made the idea vivid. We forget the impression, but the vivacity of the idea will remain.

§243 The Mental State of Recalling Past Mental States

Now consider also when we remember some idea. That recollection then is an idea of an idea. But sometimes such recollections seem to have greater vivacity than the loose conceptions of our imagination. These remembered ideas are not immediately recalled by impressions. However, we do not just recall the ideas we previously had. We also recall the mental states we had while previously conceiving those ideas. So if there was much force and vivacity in our prior conception, then when we recall it, we will evoke those forces as well.

In thinking of our past thoughts we not only delineate out the objects, of which we were thinking, but also conceive the action of the mind in the meditation, that certain je-ne-scai-quoi, of which 'tis impossible to give any definition or description, but which every one sufficiently understands. (106bc)

§244 We Now Understand the Causes of Beliefs

We now understand how we form ideas and ideas of impressions, and also how we believe in the these impressions' and ideas' existence.

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From the Original Text:

Sect. viii. Of the Causes of Belief.
Having thus explained the nature of belief, and shewn that it consists in a lively idea related to a present impression; let us now proceed to examine from what principles it is derived, and what bestows the vivacity on the idea.
I would willingly establish it as a general maxim in the science of human nature, that when any impression becomes present to us, it not only transports the mind to such ideas as are related to it, but likewise communicates to them a share of its force and vivacity. All the operations of the mind depend in a great measure on its disposition, when it performs them; and according as the spirits are more or less elevated, and the attention more or less fixed, the action will always have more or less vigour and vivacity. When therefore any object is presented, which elevates and enlivens the thought, every action, to which the mind applies itself, will be more strong and vivid, as Tong as that disposition continues, Now it is evident the continuance of the disposition depends entirely on the objects, about which the mind is employed; and that any new object naturally gives a new direction to the spirits, and changes the disposition; as on the contrary, when the mind fixes constantly on the same object, or passes easily and insensibly along related objects, the disposition has a much longer duration. Hence it happens, that when the mind is once inlivened by a present impression, it proceeds to form a more lively idea of the related objects, by a natural transition of the disposition from the one to the other. The change of the objects is so easy, that the mind is scarce sensible of it, but applies itself to the conception of the related idea with all the force and vivacity it acquired from the present impression.
If in considering the nature of relation, and that facility of transition, which is essential to it, we can satisfy ourselves concerning the reality of this phaenomenon, it is well: But I must confess I place my chief confidence in experience to prove so material a principle. We may, therefore, observe, as the first experiment to our present purpose, that upon the appearance of the picture of an absent friend, our idea of him is evidently inlivened by the resemblance, and that every passion, which that idea occasions, whether of joy or sorrow, acquires new force and vigour. In producing this effect there concur both a relation and a present impression. Where the picture bears him no resemblance, or at least was not intended for him, it never so much as conveys our thought to him: And where it is absent, as well as the person; though the mind may pass from the thought of the one to that of the other; it feels its idea to be rather weekend than inlivened by that transition. We take a pleasure in viewing the picture of a friend, when it is set before us; but when it is removed, rather choose to consider him directly, than by reflexion in an image, which is equally distinct and obscure.
The ceremonies of the Roman Catholic religion may be considered as experiments of the same nature. The devotees of that strange superstition usually plead in excuse of the mummeries, with which they are upbraided, that they feel the good effect of those external motions, and postures, and actions, in enlivening their devotion, and quickening their fervour, which otherwise would decay away, if directed entirely to distant and immaterial objects. We shadow out the objects of our faith, say they, in sensible types and images, and render them more present to us by the immediate presence of these types, than it is possible for us to do, merely by an intellectual view and contemplation. Sensible objects have always a greater influence on the fancy than any other; and this influence they readily convey to those ideas, to which they are related, and which they Resemble. I shall only infer from these practices, and this reasoning, that the effect of resemblance in inlivening the idea is very common; and as in every case a resemblance and a present impression must concur, we are abundantly supplyed with experiments to prove the reality of the foregoing principle.
We may add force to these experiments by others of a different kind, in considering the effects of contiguity, as well as of resemblance. It is certain, that distance diminishes the force of every idea, and that upon our approach to any object; though it does not discover itself to our senses; it operates upon the mind with an influence that imitates an immediate impression. The thinking on any object readily transports the mind to what is contiguous; but it is only the actual presence of an object, that transports it with a superior vivacity. When I am a few miles from home, whatever relates to it touches me more nearly than when I am two hundred leagues distant; though even at that distance the reflecting on any thing in the neighbourhood of my friends and family naturally produces an idea of them. But as in this latter case, both the objects of the mind are ideas; notwithstanding there is an easy transition betwixt them; that transition alone is not able to give a superior vivacity to any of the ideas, for want of some immediate impression.⁶
⁶ NATURANE NOBIS, IN QUIT, DATUM DICAM, AN ERRORE QUODAM, UT, CUM EA LOCA VIDEAMUS, IN QUIBUS MEMORIA DIGNOS VIROS ACCEPERIMUS MULTURN ESSE VERSATOS, MAGIS MOVEAMUR, QUAM SIQUANDO EORUM IPSORUM AUT JACTA AUDIAMUS, AUT SCRIPTUM ALIQUOD LEGAMUS? VELUT EGO NUNC MOVEOR. VENIT ENIM MIHI PLATONIS IN MENTEM: QUEM ACCIPIMUS PRIMURN HIC DISPUTARE SOLITUM: CUJUS ETIAM ILLI HORTULI PROPINQUI NON MEMORIAM SOLUM MIHI AFFERUNT, SED IPSUM VIDENTUR IN CONSPECTU MEO HIC PONERE. HIC SPEUSIPPUS, HIC XENOCRATES, HIC EJUS AUDITOR POLEMO; CUJUS IPSA ILLA SESSIO FUIT, QUAM VIDEAMUS. EQUIDEM ETIAM CURIAM NOSTRAM, HOSTILIAM DICO, NON HANC NOVAM, QUAE MIHI MINOR ESSE VIDETUR POST QUAM EST MAJOR, SOLE BARN INTUENS SCIPIONEM, CATONEM, LACLIUM, NOSTRUM VERO IN PRIMIS AVUM COGITARE. TANTA VIS ADMONITIONIS INEST IN LOCIS; UT NON SINE CAUSA EX HIS MEMORIAE DUCTA SIT DISCIPLINA. Cicero de Finibus, lib. 5.
[“Should I, he said, “attribute to instinct or to some kind of illusion the fact that when we see those places in which we are told notable men spent much of their time, we are more powerfully affected than when we hear of the exploits of the men themselves or read something written? This is just what is happening to me now; for I am reminded of Plato who, we are told, was the first to make a practice of holding discussions here. Those gardens of his near by do not merely put me in mind of him; they seem to set the man himself before my very eyes. Speusippus was here; so was Xenocrates; so was his pupil, Polemo, and that very seat which we may view was his.
“Then again, when I looked at our Senate-house (I mean the old building of Hostilius, not this new one; when it was enlarged, it diminished in my estimation), I used to think of Scipio, Cato, Laelius and in particular of my own grandfather.
“Such is the power of places to evoke associations; so it is with good reason that they are used as a basis for memory training.”]
No one can doubt but causation has the same influence as the other two relations; of resemblance and contiguity. Superstitious people are fond of the relicks of saints and holy men, for the same reason that they seek after types and images, in order to enliven their devotion, and give them a more intimate and strong conception of those exemplary lives, which they desire to imitate. Now it is evident, one of the best relicks a devotee coued procure, would be the handywork of a saint; and if his cloaths and furniture are ever to be considered in this light, it is because they were once at his disposal, and were moved and affected by him; in which respect they are to be considered as imperfect effects, and as connected with him by a shorter chain of consequences than any of those, from which we learn the reality of his existence. This phaenomenon clearly proves, that a present impression with a relation of causation may, inliven any idea, and consequently produce belief or assent, according to the precedent definition of it.
But why need we seek for other arguments to prove, that a present impression with a relation or transition of the fancy may inliven any idea, when this very instance of our reasonings from cause and effect will alone suffice to that purpose? It is certain we must have an idea of every matter of fact, which we believe. It is certain, that this idea arises only from a relation to a present impression. It is certain, that the belief super-adds nothing to the idea, but only changes our manner of conceiving it, and renders it more strong and lively. The present conclusion concerning the influence of relation is the immediate consequence of all these steps; and every step appears to me sure end infallible. There enters nothing into this operation of the mind but a present impression, a lively idea, and a relation or association in the fancy betwixt the impression and idea; so that there can be no suspicion of mistake.
In order to put this whole affair in a fuller light, let us consider it as a question in natural philosophy, which we must determine by experience and observation. I suppose there is an object presented, from which I draw a certain conclusion, and form to myself ideas, which I am said to believe or assent to. Here it is evident, that however that object, which is present to my senses, and that other, whose existence I infer by reasoning, may be thought to influence each other by their particular powers or qualities; yet as the phenomenon of belief, which we at present examine, is merely internal, these powers and qualities, being entirely unknown, can have no hand in producing it. It is the present impression, which is to be considered as the true and real cause of the idea, and of the belief which attends it. We must therefore endeavour to discover by experiments the particular qualities, by which it is enabled to produce so extraordinary an effect.
First then I observe, that the present impression has not this effect by its own proper power and efficacy, and when considered alone, as a single perception, limited to the present moment. I find, that an impression, from which, on its first appearance, I can draw no conclusion, may afterwards become the foundation of belief, when I have had experience of its usual consequences. We must in every case have observed the same impression in past instances, and have found it to be constantly conjoined with some other impression. This is confirmed by such a multitude of experiments, that it admits not of the smallest doubt.
From a second observation I conclude, that the belief, which attends the present impression, and is produced by a number of past impressions and conjunctions; that this belief, I say, arises immediately, without any new operation of the reason or imagination. Of this I can be certain, because I never am conscious of any such operation, and find nothing in the subject, on which it can be founded. Now as we call every thing CUSTOM, which proceeds from a past repetition, without any new reasoning or conclusion, we-may establish it as a certain truth, that all the belief, which follows upon any present impression, is derived solely from that origin. When we are accustomed to see two impressions conjoined together, the appearance or idea of the one immediately carries us to the idea of the other.
Being fully satisfyed on this head, I make a third set of experiments, in order to know, whether any thing be requisite, beside the customary transition, towards the production of this phaenomenon of belief. I therefore change the first impression into an idea; and observe, that though the customary transition to the correlative idea still remains, yet there is in reality no belief nor perswasion. A present impression, then, is absolutely requisite to this whole operation; and when after this I compare an impression with an idea, and find that their only difference consists in their different degrees of force and vivacity, I conclude upon the whole, that belief is a more vivid and intense conception of an idea, proceeding from its relation to a present impression.
Thus all probable reasoning is nothing but a species of sensation. It is not solely in poetry and music, we must follow our taste and sentiment, but likewise in philosophy. When I am convinced of any principle, it is only an idea, which strikes more strongly upon me. When I give the preference to one set of arguments above another, I do nothing but decide from my feeling concerning the superiority of their influence. Objects have no discoverable connexion together; nor is it from any other principle but custom operating upon the imagination, that we can draw any inference from the appearance of one to the existence of another.
It will here be worth our observation, that the past experience, on which all our judgments concerning cause and effect depend, may operate on our mind in such an insensible manner as never to be taken notice of, and may even in some measure be unknown to us. A person, who stops short in his journey upon meeting a river in his way, foresees the consequences of his proceeding forward; and his knowledge of these consequences is conveyed to him by past experience, which informs him of such certain conjunctions of causes and effects. But can we think, that on this occasion he reflects on any past experience, and calls to remembrance instances, that he has seen or heard of, in order to discover the effects of water on animal bodies? No surely; this is not the method, in which he proceeds in his reasoning. The idea of sinking is so closely connected with that of water, and the idea of suffocating with that of sinking, that the mind makes the transition without the assistance of the memory. The custom operates before we have time for reflection. The objects seem so inseparable, that we interpose not a moment’s delay in passing from the one to the other. But as this transition proceeds from experience, and not from any primary connexion betwixt the ideas, we must necessarily acknowledge, that experience may produce a belief and a judgment of causes and effects by a secret operation, and without being once thought of. This removes all pretext, if there yet remains any, for asserting that the mind is convinced by reasoning of that principle, that instances of which we have no experience, must necessarily resemble those, of which we have. For we here find, that the understanding or imagination can draw inferences from past experience, without reflecting on it; much more without forming any principle concerning it, or reasoning upon that principle.
In general we may observe, that in all the most established and uniform conjunctions of causes and effects, such as those of gravity, impulse, solidity, &c. the mind never carries its view expressly to consider any past experience: Though in other associations of objects, which are more rare and unusual, it may assist the custom and transition of ideas by this reflection. Nay we find in some cases, that the reflection produces the belief without the custom; or more properly speaking, that the reflection produces the custom in an oblique and artificial manner. I explain myself. It is certain, that not only in philosophy, but even in common life, we may attain the knowledge of a particular cause merely by one experiment, provided it be made with judgment, and after a careful removal of all foreign and superfluous circumstances. Now as after one experiment of this kind, the mind, upon the appearance either of the cause or the effect, can draw an inference concerning the existence of its correlative; and as a habit can never be acquired merely by one instance; it may be thought, that belief cannot in this case be esteemed the effect of custom. But this difficulty will vanish, if we consider, that though we are here supposed to have had only one experiment of a particular effect, yet we have many millions to convince us of this principle; that like objects placed in like circumstances, will always produce like effects; and as this principle has established itself by a sufficient custom, it bestows an evidence and firmness on any opinion, to which it can be applied. The connexion of the ideas is not habitual after one experiment: but this connexion is comprehended under another principle, that is habitual; which brings us back to our hypothesis. In all cases we transfer our experience to instances, of which we have no experience, either expressly or tacitly, either directly or indirectly.
I must not conclude this subject without observing, that it is very difficult to talk of the operations of the mind with perfect propriety and exactness; because common language has seldom made any very nice distinctions among them, but has generally called by the same term all such as nearly resemble each other. And as this is a source almost inevitable of obscurity and confusion in the author; so it may frequently give rise to doubts and objections in the reader, which otherwise he would never have dreamed of. Thus my general position, that an opinion or belief is nothing but a strong and lively idea derived from a present impression related to it, maybe liable to the following objection, by reason of a little ambiguity in those words strong and lively. It may be said, that not only an impression may give rise to reasoning, but that an idea may also have the same influence; especially upon my principle, that all our ideas are derived from correspondent impressions. For suppose I form at present an idea, of which I have forgot the correspondent impression, I am able to conclude from this idea, that such an impression did once exist; and as this conclusion is attended with belief, it may be asked, from whence are the qualities of force and vivacity derived, which constitute this belief? And to this I answer very readily, from the present idea. For as this idea is not here considered, as the representation of any absent object, but as a real perception in the mind, of which we are intimately conscious, it must be able to bestow on whatever is related to it the same quality, call it firmness, or solidity, or force, or vivacity, with which the mind reflects upon it, and is assured of its present existence. The idea here supplies the place of an impression, and is entirely the same, so far as regards our present purpose.
Upon the same principles we need not be surprized to hear of the remembrance of an idea: that is, of the idea of an idea, and of its force and vivacity superior to the loose conceptions of the imagination. In thinking of our past thoughts we not only delineate out the objects, of which we were thinking, but also conceive the action of the mind in the meditation, that certain JE-NE-SCAI-QUOI, of which it is impossible to give any definition or description, but which every one sufficiently understands. When the memory offers an idea of this, and represents it as past, it is easily conceived how that idea may have more vigour and firmness, than when we think of a past thought, of which we have no remembrance.
After this any one will understand how we may form the idea of an impression and of an idea, and how we way believe the existence of an impression and of an idea.