Impressions are distinguished from ideas by experience. The difference is the degree of vivacity.
If nothing is distinguishable in an idea it is simple; otherwise complex.
Impressions and ideas resemble each other in all other respects but force and vivacity. They are always doubled up. The idea is a reflection of the impression.
Exception: complex ideas may lack complex impressions as originals.
Thesis: All simple ideas are derived from, correspondent to, and exaclty resemble simple impressions.
Only two proofs of this, but they are both conclusive.
Contradictory phenomenon: missing shade of blue. One has no impression of a single shade of blue, though having impressions of all the rest. It seems possible under these conditions still to have an idea of that shade. So the maxim (no idea except from an impression) does not hold for every case, but the exception does not merit altering the general principle
Some philosophers (e.g. Plato and Descartes) have claimed that there are "innate" or inborn ideas from which we might derive knowledge. But Hume asserts that any argument that claims to establish that there are original ideas at bottom only testifies to the existence of impressions.
There are two kinds of impressions: those of sensation and reflection. Examples of impressions of sensation are those of heat/cold, thirst/hunger, pleasure/pain. Reflection gives us impressions of desire/aversion, hope/fear. We do not know what causes the mind to have sensations, but we can say that those of reflection are the outcome of a process beginning with impressions of sensation, from which we get ideas of pleasure and pain. For example, touching a stove, my hand becomes painful. The idea of pain I get in this way gives rise to an impression of aversion to touching the stove again.
Hume will begin with ideas, rather than impressions. How we get impressions of sense is primarily a matter for science. The impressions of reflection, the fears, hopes etc., which are so important to us, derive from ideas, as was just shown. So the investigation will begin with ideas, even though what is first in time is the impressions.
When an impression is revived as an idea, it may retain some of the force of the impression, as in memory, or it may be a "perfect" idea (lacking in force), as in imagination.
Another difference between memory and imagination is that memory is constrained to a certain order by the order of the past impressions, while imagination is not. Hume here first broaches a principle that where there is a difference in ideas, the ideas can be separated and produced separately. This is how we can re-arrange our experience to produce fiction: our imagination is at liberty to change our ideas around.
Given the theoretically unlimited combinations of ideas, we couldn't account for the actual operations of the mind without a general principle. There is a force, only a gentle one, like the force of attraction. [For Newton, this force is unexplained.]
Three principles of the association of ideas account for the connections we find among them:
There are two kinds of relations, natural and philosophical. The group just given is natural. The philosophical are:
What else are substances than complexes of ideas and what else are modes than the ideas making up the complex? The idea of substance is only that of a collection of simple ideas, united by the imagination. And no substance is known through reflection Should we add an unknown something, what Aristotle called the substratum? Hume will answer in the negative.
All impressions and ideas are conceived as existent: from this we derive the "most perfect idea and assurance of being ."
A dilemma: the idea of existence must be derived from a distinct impression conjoined with every perception, or it must be the same as the idea. The dilemma arises from the principle that every idea arises from a similar impression. The idea is not derived from a distinct impression, because it is not separable from it. No one can produce the distinct impression: it is "impossible."
"The idea of existence, then, is the very same with the idea of what we conceive to be existent."
The notion of a distinction of reason (between the existing thing and the existence of the thing) does not help, because no object can differ with any other with respect to existence.
External existence goes the same route. All that is really present to the mind is its perceptions. We cannot conceive of anything specifically different from them. An argument similar to one given by the Irish philosopher George Berkeley is given: any attempt to conceive of something different remains a perception. The most we can do is to "attribute to them different relations, connexions and durations." See Part IV, § 2.
"Relations of ideas" are those depending entirely on ideas. (e.g. Triangle's relations of angles)
The relations are: Resemblance, contrariety, degrees in quality (discoverable at first sight), proportions in quantity or number (only discoverable at first sight when very simple, otherwise requiring artificial means: the "prodigious minuteness of which nature is susceptible" leaves us with no precise standards, though the minute objects are so insignificant as to cause little harm. Algebra and arithmetic, on the other hand, deal with unities).
The rationalism of philosophers such as Plato and Descartes held the notion that the "refined and spiritual" objects of mathematics are "comprehended by a pure and intellectual view, of which the superior faculties of the soul are alone capable." But this only covers their errors. This is destroyed by the copy maxim. What is in the idea can only be what is in the impression, and hence "cannot imply any great mystery."
"Relations fact" are those which may be changed without changing the idea.
(Contiguity, distance: object's place only changes. [its intrinsic properties stay the same])
(Identity: qualitatively identical objects may be numerically different)
(Causation: the power is not discoverable from the idea, "the qualities of the objects, as they appear to us")
This section will explain those three relations which may vary though the object remains the same.
Reasoning involves the comparison of ideas, but when both are present, there is perception only. Thus there is no reasoning regarding identity and relations of timeand place. Only causation does not require the presence of both objects, but allows us from the presence of one to "give us assurance" of the existence of another.
Cause and effect is what governs our reasoning about identity and spatio-temporal relations. If we think objects are invariably adjacent or separate, it is because we think there is a secret cause connecting them or separating them. With identity, perfect resemblance is not enough, we need a cause connecting this perception to a pervious one.
We cannot reason correctly without an understanding of our idea of cause, and hence finding its origin "and examining the primary impression, from which it arises."
It is no one quality, for there is no single quality which belongs to all beings; yet any one can be deemed cause or effect. So we must look to relation among objects.
Every object considered as cause or effect is contiguous. "Commonly" it is found that objects appearing to act at a distance are linked in a chain of contiguous objects. We presume the connection to exist even when we do not find one. [Newton] So CONTIGUITY will be considered essential to the relation of causation.
Also essential is the relation of PRIORITY in time of the cause before the effect. Some claim that causality can be contemporaneous. 1) experience apparently contradicts this, 2) an inference to this conclusion may be given. Claim: If one cause were contemporaneous with its effect, all would be [argument is unclear], and the succession requisite for time would be abolished. At any rate, we can suppose this to be correct, as it is of no great moment.
Consideration of a single instance yields nothing more than contiguity and precedence. It does no good to say that the first produces the second, since explanation of production would invoke causation, resulting in circularity.
But we cannot rest with contiguity and succession, since they may exist without our considering that there is a causal relation. We must add a NECESSARY CONNEXION, a relation of far more importance than the first two.
What impressions give rise to the idea of a necessary connection? It is no known quality, and only the relations of contiguity and succession may be found. It would be wrong to back off the previously established principle that ideas are copies of impressions. So we must grope blindly for one, looking elsewhere for hints.
"First, For what reason we pronounce it necessary, that every thing whose existence has a beginning, shou'd also have a cause.
"Secondly, Why we conclude, that such particular causes must necessarily have such particular effects; and what is the nature of the inference we draw from the one to the other, and of the belief we repose in it."
Although emphasis is on the relation derived from impressions of sensation, those of reflection admit no less of the relation of cause and effect, connecting our passions.
"'Tis a general maxim in philosophy, that whatever begins to exist, must have a cause of existence." This is used in our reasoning and taken as intuitive; however, there is in it "no mark of any such intuitive certainty" but is quite foreign to conviction.
Certainty is confined to comparisons of ideas present (see section i, the four relations admitting of such comparison). These are not "implied in" the maxim, so it is not intuitively certain, unless another kind of relation can be found.
In fact, it is neither intuitively nor demonstratively certain. For we can conceive of an object non-existent at one moment and existent at the next. The ideas of cause and beginning of existence are distinct and hence separable. There is no contradiction in the imagining of such a thing, so there is no demonstration of the necessity of the maxim.
Some fallacious demonstrations. Hobbes: without a cause, there would be nothing to determine the existence of anything at a specific time, all times being alike. But both the that and the when or where stand or fall on the same footing. If it is absurd to say that without a cause a thing begins to exist at a time and place like all others, then it is absurd to say that it begins there with a cause.
Clarke: What lacks a cause would produce itself, hence "exist before it existed; which is impossible." But this begs the question: in denying that there is a cause, we grant that there must be one, namely, the object itself. The allegedly absurd hypothesis, that the object had no cause, excludes the thing itself.
Locke: What lacks a cause is produced by nothing, but nothing produces nothing. But this depends on the same fallacy [begging the question: it is assumed not to be produced, yet is produced by nothing].
If everything has a cause, then if the cause is not something else it is either itself or nothing. But that is what is in question.
A worse argument: the idea of cause is implied in that of effect. This says nothing about whether a beginning of existence is an effect.
So, the maxim is not based on "knowledge or any scientific reasoning." The only remaining source is observation and experience. So how does experience give rise to such a maxim? It will be "convenient" to consider instead the particular case, i.e., "Why we conclude, that such particular causes must necessarily have such particular effects, and why we form an inference from one to another."
In all our causal reasoning, we must begin with "some object, which we see or remember." The impressions of sense and memory are the only stoppers of a regress. Without a fixed stopping point, "there wou'd be no belief nor evidence." Hypothetical arguments are in fact this way.
We need not be able to call up the original impression: the memory of the conviction it produced is enough, as with a demonstration.
Now that we have figured out particular transitions, we ask again "What is our idea of necessity, when we say that two objects are necessarily connected together." What is the impression which gives rise to it?
The two objects are contiguous and successive, but no other relation can be perceived. The view is enlarged to include other like objects in like relations. The determinationto produce a like idea upon frequent repetition serves duty for the impression.
But WATCH OUT, since this conclusion bears on "one of the most sublime questions of philosophy, viz. that concerning the power and efficacy of causes."
What is the idea of efficacy, agency, power, force, energy, necessity, connexion, and productive quality ("all nearly synonymous). Watch for circular definitions; seek the impressions instead (simple or compound, as appropriate).
A popular explanation is to posit a power such as is capable of producing new productions in matter that are experienced. But reason cannot justify such a positing, so the idea must come from particular instances. But where is the efficacy "plainly discoverable to the mind" or its operations obvious? It is not innate.
We have all kinds of explanations, substantial forms, accidents or qualities, matter and form, form and accidents, virtues and faculties.
These principles are unintelligible and inexplicable: philosophers would not have had recourse to them if there were an intelligible substitute.
So, perhaps it is unknown. The Cartesians claim that matter is inefficacious, so they have recourse to the DEITY. But this can be sustained only on the false presumption of innate ideas, since we have no impression of force, so we could have none of a deity. To avoid this impiety, we should conclude that there is no idea of force at all.
If you attribute power to matter, it must lie in an unknown quality, but then there can be no idea of it.
An idea of power in general would have to come from ideas of particular powers in an object. But this leads us back to a demonstration from the one object to the other.
Back to repetition. The idea of power cannot be something new discovered through repetition. There is nothing new produced upon repetition of cases, either.
Observation of repetition produces a new impression in the mind. "We immediately feel a determination of the mind to pass from one object to its usual attendant, and to conceive it in a stronger light upon account of that relation." This is the only effect of resemblance, so it is the idea of power derived from it. Necessity is an internal impression of the mind, an idea of reflexion, "that propensity, which custom produces, to pass from an object to the idea of its usual attendant." Necessity exists in the mind, not in objects.
Comparison made with the necessity lying in the act of the understanding comparing ideas.
This is the most violent paradox in the treatise. Though the proof is straightforward and simple, it will be resisted. The mind "spreads itself" on the objects of the senses, e.g. as with primary and secondary qualities.
But were there no mind existent? To make causes depend on thought reverses the order of nature.
We should not use the idea of power to signify something else which we do not know. Contiguity and succession are independent of the mind.
The reasoning can be applied to the impression/idea succession as well. "The uniting principle among our internal perceptions is as unintelligible as that among external objects, and is not known to us any other way than by experience."
Definition of a CAUSE: 'An object precedent and contiguous to another, and where all the objects resembling the former are plac'd in like relations of precedency and contiguity to those objects, that resemble the latter.'
'A CAUSE is an object precedent and contiguous to another, and so united with it, that the idea of the one determines the mind to form the idea of the other, and the impression of the one to form a more lively idea of the other.'
Corollaries. 1) All causes are of the same kind (formal, efficient, material, final). There is no distinction between cause and occasion. 2) There is only one kind of necessity (physical and moral). Take away necessity and you have chance. There is no distinction between power and its exercise. 3) There is no necessity "that every beginning of existence sho'd be attended with such an object" precedent an contiguous, etc. Or that a lively idea of the right kind will be produced: that one is produced ever is "perfectly extraordinary." 4) We have no reason to believe an object exists if we cannot form an idea of it.
The rules in demonstrative sciences are infallible, but the application is uncertain. We must form a second judgment, a control, and keep track of our accuracy over time. Reason is a cause whose effects may be truth or not, so our tracking generates probabilities, which are "greater or less, according to our experience of the veracity or deceitfulness of our understanding, and according to the simplicity or intricacy of the question."
Mathematics is an example: we double-check, ask our peers, see the response to publication.. All this leads to higher probabilities. So, too, the process of accounting.
Knowledge and probability are contrary, "must be entirely present , or entirely absent." Even the simplest addition, then, is suspect, since if it were knowledge, then a total sum would be, "unless the whole can be different from all its parts."
The foundation of probability. Just as reason requires correction, judgments of probability are subject "to a new correction by a reflex act of the mind, wherein the nature of our understanding, and our reasoning from the first probability become our objects." This takes into account our judgment and experience.
We have, now, the uncertainty of the original judgment and that from the weakness of the faculties. There is a third, "deriv'd from the possibility of error in the estimation we make of the truth and fidelity of our faculties." A regress then diminishes the original probability to "at last a total extinction of belief and evidence."
The inculcation of this argument does not mean the Hume is a skeptic. "Nature, by an absolute and uncontroulable necessity has determin'd us to judge as well as to breathe and feel."
The role of the argument, then, is to confirm the account of causal reasoning (custom) and of belief (sentiment). If belief "were a simple act of thought, without any peculiar manner of conception, or the addition of a force and vivacity, it must infallibly destroy itself, and in every case terminate in a total suspense of judgment." Beliefs cannot be destroyed by "mere ideas and reflections."
Still, it seems that the belief ought to be diminished by the continual questioning. The answer is that after the uncertainty of the object and the fallibility of the senses are considered, the influence of the principles have little effect. It is a diversion from the usual channel.
Metaphysic is an example of the straining of our thought, where
arguments have little impact. There is a fixed amount of energy
the mind has, and it is exhausted at the higher levels.
We should not write off skepticism with the false dilemma:
Instead, they begin strong, then diminish the force of reason, but this diminishes its own power, until "at last they both vanish away into nothing." Skeptical arguments can never destroy themselves unless reason is destroyed as well.
[Note: the entire section from the Treatise is covered here.]
Some philosophers think that we have "certainty, beyond the evidence of a demonstration," of the identity and simplicity of the SELF. Every perception indicates it.
But we have no such idea, since there is no impression, and "self or person is not any one impression, but that to which our several impressions and ideas are suppos'd to have a reference." The requisite impression would have to "continue invariably the same," but "there is no impression constant and invariable." The variable impressions, on the other hand, are not co-existent.
Since our particular perceptions are separable, etc., they have no need of a self as support. "After what manner, therefore, do they belong to self; and how are they connected with it?" Upon cessation of my perceptions, I cease to exist, and I will be annihilated after death. Anyone who asserts the existence of himself could be right, but he would have to "perceive something simple and continu'd, which he calls himself; tho' I am certain there is no such principle in me."
Everyone else is just "a bundle or collection of different perceptions, which succeed each other with an inconceivable rapidity, and are in a perpetual flux and movement." Senses are changing all the time, and thought the more so: all powers of the soul never rest. "The mind is a kind of theatre, where several perceptions successively make their appearance; pass, re-pass, glide away, and mingle in an infinite variety of postures and situations." There is no simplicity at one time or identity at different times. We have no notion of place of the theatre or the materials making up the show.
To understand the propensity to believe in identity, we must distinguish thought and imagination from passions and self-concern . The former is of concern. We will make an analogy between the identity of plants and animals and that of persons.
We have ideas of identity and distinctness corresponding to, respectively, the invariable and uninterrupted, and the succession of related objects. The two are generally confounded, though they are different. The relation smoothes the transition, so that the two feel the same. "This resemblance is the cause of the confusion and mistake, and makes us substitute the notion of identity, instead of that of related objects." We cannot resist this bias, and in the end we "boldly assert that these different related objects are in effect the same, however interrupted and variable." To justify this, we feign a principle: the uninterrupted existence of perceptions, and soul, self, substance or something unknown or mysterious (cf. Shaftsbury). This holds for the identity of plants and vegetables as well. Even without these devices, we still feel a propensity to confound these ideas.
The dispute over identity is not merely verbal, as it involves these fictions. The relation of parts is really all that is needed to account for every day experience: "all objects, to which we ascribe identity, without observing their unvariableness and uninterruptedness, are such as consist of a succession of related objects."
A mass which suffers no augmentation or diminution is identical, and the slightest addition or subtraction makes it a different thing [c.f. Locke]. But we still count it the same, "where we find so trivial an alteration." The passage is too smooth to move us to count a difference.
The dimensions of the overlooked change are proportional to the size of the whole: a mountain's removal does not affect identity judgments about planets, though change of an inch's worth can do so for smaller objects. This locates the attribution of difference to a difference in appearance, so "it must be the uninterrupted progress of the thought, which constitutes the imperfect identity."
Another confirmation is that an instantaneous change is accounted difference, while a very slow change is not. Once again, the explanation is an easy passage.
Common end is another inducer to judge things identical. The sameness of the end "affords an easy transition of the imagination from one situation of the body to another." Ship example is used: we do ascribe identity to it.
Adding sympathy of parts to common end, "reciprocal relation of cause and effect in all their actions and operations," is the next step, "still more remarkable" in its ability to induce judgments of identity. This allows attribution of identity through total change of parts, as with animals and plants.
Another remarkable phænomenon is the confusion of numerical identity and the identity of kinds ("specific," of species). A repeated noise may be said to be the same. A church of brick entirely built of free-stone is said to be the same just because of the relation to the parishioners. (It helps that the whole first church was gone, so that they did not co-exist.)
Still another: We are more tolerant of greater change when this is "natural and expected," as with a river, "tho' in less than four and twenty hours these [parts] be totally alter'd; this hinders not the river from continuing the same during several ages."
Now to personal identity. The reasoning that explained the identity of plants, etc. is brought to bear on the self; but it is fictitious.
Perceptions are different, distinguishable, separable: these are "essential to them." When we unite them by identity, we must ask whether it is "something that really binds our several perceptions together, or only associates their ideas in the imagination." Do we observe a real bond or merely feel one? The understanding never observes a relation of real connection ." Identity is in the same category as cause and effect , a "customary association of ideas." Identity depends on resemblance, contiguity, causation. Without these there is no reason to think any of them related at all.
Contiguity "has little or no influence in the present case."
What about resemblance? Memory contributes to the production of identity by "producing the relation of resemblance among our perception."
Causation. There are productions, destructions, influences, and modifications of ideas by ideas. "One thought chaces another, and draws after it a third, by which it is expell'd in its turn. In this respect, I cannot compare the soul more properly to any thing than to a republic or commonwealth, in which several members are united by the reciprocal ties of government and subordination, and give rise to other persons, who propagate the same republic in the incessant changes of its parts." Laws, constitutions, are like character and disposition. This finally brings in the passions: our concern for the future is based on this unity.
Only on the possession of memory do we have a notion of personal identity. Once we have the notion of causation, we can extend it beyond memory (which really does not go very far). Thus memory discovers personal identity.
All disputes concerning identity are strictly verbal "except so far as the relation of parts gives rise to some fiction or imaginary principle of union."
The reasoning may be extended to simplicity. From similarity of operation on the understanding, we take tightly bound complex objects to be simple.
This concludes the discussion of the human understanding. Almost time to turn to "the accurate anatomy of human nature."
The completion of the task seems impetuous: my previous errors, the weakness of the faculties, and the impossibility of amending them "reduces me almost to despair, and makes me resolve to perish on the barren rock, on which I am at present, rather than venture myself upon that boundless ocean, which runs out into immensity. This sudden view of my danger strikes me with melancholy; and as 'tis usual for that passion, above all others, to indulge itself' I cannot forbear feeding my despair, with all those desponding reflections, which the present subject furnishes me with in such abundance."
Solitude is frightening: am I a "strange uncouth monster" unfit for human company. Those whose systems I have brought down will offer me no companionship in my despair. "When I look abroad, I foresee on every side, dispute, contradiction, anger, calumny and detraction. When I turn my eye inward, I find nothing but doubt and ignorance."
Many infirmities are shared by all humans. Here is a summary of our situation. We can only assent due to the feeling of "a strong propensity to consider objects strongly in that view, under which they appear to me." Experience and habit are principles that operate on the imagination to produce stronger reactions than others. We even need this to consider what is present to our senses as objects, and the succession of perceptions as the self. Otherwise we are stuck in the present, without even memory. "The memory, senses, and understanding are, therefore, all of them founded on the imagination, or the vivacity of our ideas."
But these principles sometimes present a conflict: cause and effect (yielding the primary/secondary quality distinction) and continued existence of matter (depending on secondary qualities).
But this is not the only indignity. We seek for causes and effects, working from the immediate to the remote, to the "efficacious quality, on which the tie depends." But this is to be found merely in ourselves, the determination of the mind to make a transition. "Such a discovery not only cuts off all hope of ever attaining satisfaction, but even prevents our very wishes; since it appears, that when we say we desire to know the ultimate and operating principle, as something, which resides in the external object, we either contradict ourselves, or talk without a meaning."
We do not have these scruples ordinarily, but this presents a dilemma. We should not assent to "every trivial suggestion of the fancy."
On the other hand, the understanding acting alone "entirely subverts itself, and leaves not the lowest degree of evidence in any proposition, either in philosophy or common life." The only thing we have going for us is easy transition. "Shall we, then, establish it for a general maxim, that no refin'd or elaborate reasoning is ever to be receiv'd? Consider well the consequences of such a principle. By this means you cut off entirely all science and philosophy: You proceed upon one singular quality of the imagination, and by a parity of reason must embrace all of them: And you expresly contradict yourself; since this maxim must be built on the preceding reasoning, which will be allow'd to be sufficiently refin'd and metaphysical." So there is no choice between a false reasoning and none at all. Hume doesn't know what to do, but he recognizes that it has no lasting effect on him. Still, "We do not, and cannot establish it for a rule, that they ought not to have any influence; which implies a manifest contradiction."
But the refined speculations do have a a strong effect, an intense view of the contradictions have heated his brain. He asks what he can believe. "I am confounded with all these questions, and begin to fancy myself in the most deplorable condition imaginable, inviron'd with the deepest darkness, and utterly depriv'd of the use of every member and faculty."
Nature dispels the clouds: I play a game of backgammon, and I do not afterwards even want to think of these things.
Even though he can't bring himself to be a complete skeptic, he is still mighty suspicious. He will not wander into the solitude any more: "If I must be a fool, as all those who reason or believe anything certainly are, my follies shall at least be natural and agreeable."
As philosophers, we assent only when reason is lively, where, the cost of scepticism is too high, yet "we ought still to preserve our scepticism."
Curiosity, though, inclines Hume to inquire about the principles of moral good and evil, government, the passions, etc. The origin of his philosophy is a feeling of pleasure in the pursuit.
Philosophy provides an outlet for our natural desire to open up new worlds beyond the narrow compass of experience. It is not dangerous like superstition: "Generally speaking, the errors in religion are dangerous; those in philosophy only ridiculous."
Hume does not pretend to make philosophers of those who actually are satisfied with a completely domestic life. Rather than convert them to philosophers, it would be better to bring a measure of their gravity to philosophy. "While a warm imagination is allow'd to enter into philosophy, and hypotheses embrac'd merely for being specious and agreeable, we can never have any steady principles, nor any sentiments, which suit with common practice and experience." Without the extravagant hypothesis, we can produce a system "which if not true (for that, perhaps, is so much to be hop'd for) might at least be satisfactory to the human mind, and might stand the test of the most critical examination." We really haven't been at it that long. Human nature is the only object of our science, and it has been neglected. Maybe Hume can bring it into fashion, thus recovering from his spleen. He will philosophize in a careless manner, which at least allows him to get started.
We can give in to the propensity to assertion of particular points at particular instants. We may even use such strong language as "'tis evident, 'tis certain, 'tis undeniable ." But they are just sentiments, not dogmatism, which is unbecoming to all, and much more so to a skeptic.