A Critique of Hume's Theory of Ideas

 

In Hume the term ‘perception’ replaces Locke’s ‘Ideas’, as the object of understanding:

 

“It has been observ’d, that nothing is ever present to the mind but its perceptions; and that all the actions of seeing, hearing, judging, loving, hating, and thinking, fall under this denomination. The mind can never exert itself in any action, which we may not comprehend under the term of perception; and consequently that term is no less applicable to those judgments, by which we distinguish moral good and evil, than to every other operation of the mind. To approve of one character, to condemn another, are only so many different perceptions.” (All page citations are from D.F. Norton’s edition of Treatise on Human Nature: 293).

 

Perception is whatever is present to the mind (THN: 408), they are objects intimately present to the mind (137), they are our only objects (141,293), they are interrupted and perishing and different at every return (140), like the Heracletean flux. Further ‘Perceptions’ are divided into impressions and ideas, depending on the force and liveliness of perceptions:

 

“All the perceptions of the human mind resolve themselves into two distinct kinds, which I shall call IMPRESSIONS and IDEAS. The difference betwixt these consists in the degrees of force and liveliness, with which they strike upon the mind, and make their way into our thought or consciousness. Those perceptions, which enter with most force and violence, we may name impressions; and under this name I comprehend all our sensations, passions and emotions, as they make their first appearance in the soul. By ideas I mean the faint images of these in thinking and reasoning; such as, for instance, are all the perceptions excited by the present discourse, excepting only, those which arise from the sight and touch, and excepting the immediate pleasure or uneasiness it may occasion. I believe it will not be very necessary to employ many words in explaining this distinction. Every one of himself will readily perceive the difference betwixt feeling and thinking. The common degrees of these are easily distinguish’d; tho’ it is not impossible but in particular instances they may very nearly approach to each other. Thus in sleep, in a fever, in madness, or in any very violent emotions of soul, our ideas may approach to our impressions: As on the other hand it sometimes happens, that our impressions are so faint and low, that we cannot distinguish them from our ideas. But notwithstanding this near resemblance in a few instances, they are in general so very different, that no one can make a scruple to rank them under distinct heads, and assign to each a peculiar name to mark the difference.” (7)

 

In a footnote Hume warns:

 

“By the term of impression I wou’d not be understood to express the manner, in which our lively perceptions are produc’d in the soul, but merely the perceptions themselves.”

 

In many places throughout the Treatise Hume emphasizes that it is on the degree of vivacity or force that the distinction between Ideas and Impressions are based, the former is simply a less lively perception. Yet as we can see in the passage quoted above (7), in some cases like fever or madness the vivacity or force of our Ideas may approach our impressions whereas in some cases impressions may be faint and low, in which case force and vivacity of Ideas cannot be the distinctive feature on which the difference between Ideas and Impressions could be based. One may note that not just above but in many places Hume contends that the force and vivacity of Ideas can equal Impressions (82-83, 206, 208, 104, 240-1, 302). Waxman’s (2005 and 1994) solution is to take the locus of force and vivacity within consciousness which being struck by a perception so to say, gives rise to certain affections with variable degrees of force, which variation does not affect the perception itself. In Appendix to Treatise, Hume says:

 

“The second error may be found in Book 1, page 67, where I say, that two ideas of the same object can only be different by their different degrees of force and vivacity. I believe there are other differences among ideas, which cannot properly be comprehended under these terms. Had I said, that two ideas of the same object can only be different by their different feeling, I shou’d have been nearer the truth.”

 

These passages, Waxman (2005) believes lends support to his view that we should attribute to Hume a bipolar as opposed to a unipolar model of consciousness. Berkeley definitely adhered to the former but Hume does not. This means that difference in force and vivacity of consciousness would not imply difference in ideational contents. This however would follow only when Ideas and Impressions are taken to be perceptions themselves. A bipolar model of consciousness differs from a unipolar model in this that in the former but not in the latter the perceiving and the perceived are different and so force and vivacity are what allow us to distinguish perceptions even though their locus is within consciousness and not in perceptions. But even with this solution it is unclear how impressions and ideas can be regarded as perceptions at all and not simply as feelings or affections. Also this means that for Hume there is a contingent relation between consciousness and the object of consciousness. To use Husserl’s terminology the object of consciousness is both immanent and transcendent to consciousness but while Berkeley seeks to reduce the object to immanence in consciousness; Hume makes it transcendent. We will return to this point but first we need to understand what these affections are and what role they play within Hume’s philosophy:

 

“…belief is more properly an act of the sensitive, than of the cogitative part of our natures . . . some sensation or peculiar manner of conception, which ’tis impossible for mere ideas and reflections to destroy.” (123)

 

Belief is a “peculiar feeling or sentiment” (623), “a firmer conception or a faster hold we take on the object” (398), “a more vivid, lively, forcible, firm steady conception of an object”, “that act of the mind, which renders realities, or what is taken for such, more present to us than fictions, causes them to weigh more in the thought, and gives them a superior influence on the passions and imagination.” (ECHU 5.2.12). Further “An idea assented to feels different from a fictitious idea that the fancy alone presents to us.” (68).

 

Belief in the real existence of something, as an object present to the mind as opposed to merely conceived or thought or imagined, is what distinguishes between reality and fiction. A tree present in front of me and one that I imagine are differentiated solely on the basis of how it feels to have something present to oneself as opposed to merely thought. So it is the vivacity or the force of liveliness of the immediate presence of something to consciousness which is called belief by Hume and which belongs to the sensitive part of our souls rather than the propositional part which is how contemporary epistemologists see it. This force and vivacity of feeling is the source of our Idea of existence:

 

“The idea of existence, then, is the very same with the idea of what we conceive to be existent. To reflect on anything simply, and to reflect on it as existent, are nothing different from each other. That idea, when conjoin’d with the idea of any object, makes no addition to it. Whatever we conceive, we conceive to be existent. Any idea we please to form is the idea of a being; and the idea of a being is any idea we please to form. Whoever opposes this, must necessarily point out that distinct impression, from which the idea of entity is deriv’d, and must prove, that this impression is inseparable from every perception we believe to be existent. This we may without hesitation conclude to be impossible.” (48)

 

Hume takes consciousness to be reflected thought or perception (400), a lively forceful perception is taken up within reflected thought to form an Idea of existence. Reflected thought is nothing apart from conceiving something, which is to have an Idea of something. Further this Idea of existence does not add anything to the content of the thought of an object because to conceive is to conceive as existent. To form an Idea of an object is the same as to form an Idea of something as existent. We see further in the passage Hume asks for a ‘distinct impression’ from which an Idea of an entity is derived and further there is a condition that this impression must be inseparable from ‘every perception we believe to be existent’. Now the idea of an entity or an object in general is not an idea of an actual existent, whereas the impression from which we need to derive the idea of an object is one which we believe to be existent, which belief is the to the effect of immediate presence of something (perception) to consciousness, it is the belief in actual existence of something. Since an Idea is a duller impression, what Hume is doing is, he is equating the conception of an entity or an object in general with a dull impression of something that actually exists and thereby we have a conception of a possible object.

 

This leads to another question – how is vivacity transferred from impressions to ideas? This brings us to Hume’s primary principle of union of ideas which creates for us a stable system of objects and judgements within the Heracletean flux of perceptions. This principle is the feeling of facility, which is felt within consciousness on occasion of making a transition from one perception to another. No genuine relations exist within Hume’s philosophy, relations are not sensed because the object of perception is confined to the here and now and so only perceptions are apprehended but no relation between perceptions are grasped. But the mind or an associative imagination feels a certain pleasure or comfort in this movement from one perception to another and hence it conjoins them whereas the feeling of discomfort leads to dividing them. The feeling is purely subjective and hence this facility of transition is regarded by Hume to be the essence of natural relation (69, 35, 145, 169-70). Waxman’s (2005: 466-67) explanation may be cited here:

 

“If, as Hume supposed, a relation is a transition of thought, he still needed to specify what it is about transitions of thought that confers on them the status of relations. For if the scene played out in Hume’s “theatre of the mind” is indeed one of “perpetual flux and movement,” and “Our thought is still more variable than our sight” (THN 252–3/165), then transitions between perceptions are continuously occurring without their being in every case related as a result. The perception of transitions is necessary, but not sufficient, to form an idea of a relation between that from and to which the transition is made; there must be something else—some associating, or relating, quality—of which we are conscious in some transitions that is lacking in others, in which ideas of relations between the perceptions concerned in them consists. Facility feeling is, in my view, the “very nature or essence” of relation for Hume because it answers the question what datum, or content, immediately present to our consciousness constitutes the difference between a transition in thought from one perception to another that is distinct from yet also related to it, and a transition from one perception to another that is distinct from and alien to it. In the former case, there is something to link the perceptions in imagination, and their sequence acquires the potential to figure in our thought and action. In the latter case, their sequence is indiscernible from mere succession, and so a matter of indifference to our thought and action. An unconscious mechanism, triggered by the appearance of some object to produce an idea of the object that had in the past been found to be constantly conjoined with it, would not be sufficient to relate the perceptions involved in a transition of thought. For in the absence of any perceptible associating quality to link them in our thought, how would their sequential presence to our consciousness be marked out from any of the perceptual sequences simultaneous with theirs? If we were conscious of nothing more in the transition from the one to the other than we are in the transitions involving any of the impressions and ideas simultaneous with them, then there would be nothing more to relate them to one another in our imaginations than to any of these other perceptions.”

 

What is important is not simply that a facility feeling be felt within imagination but that it also must register itself as a distinguishing feature between perceptions which is an important point to note because what is transferred from impression to ideas is not simply a feeling but also the content of these states itself and the relation between the content of one with another which within reflected thought is the forming of the idea of relation – of two things related to one another. Hume distinguishes between philosophical relations of contiguity, cause-effect and resemblance and natural relations. Vivacity and facility feeling are natural relations because all transitions within thought leading to acting on their basis depends on these affections and so philosophical relations are parasitic upon natural relations. At the bottom level we have natural relations which entrench a habit which gets more and more complex as more and more relations are formed or forged by the mind and at the higher level of this complexity we have a custom embedded within a system of relations, where we associate different objects as related to one another. On seeing a pearl I bend to pick it up, on feeling hunger I fetch for food, which is because custom has related these to one another which guides thought and action but these relations are underwritten by natural relations which is why I feel a pearl in my hand and food satisfies my hunger:

 

“Experience is a principle, which instructs me in the several conjunctions of objects for the past. Habit is another principle, which determines me to expect the same for the future; and both of them conspiring to operate upon the imagination, make me form certain ideas in a more intense and lively manner, than others, which are not attended with the same advantages. Without this quality, by which the mind enlivens some ideas beyond others (which seemingly is so trivial, and so little founded on reason) we cou’d never assent to any argument, nor carry our view beyond those few objects, which are present to our senses. Nay, even to these objects we cou’d never attribute any existence, but what was dependent on the senses; and must comprehend them entirely in that succession of perceptions, which constitutes our self or person. Nay farther, even with relation to that succession, we cou’d only admit of those perceptions, which are immediately present to our consciousness, nor cou’d those lively images, with which the memory presents us, be ever receiv’d as true pictures of past perceptions. The memory, senses, and understanding are, therefore, all of them founded on the imagination, or the vivacity of our ideas.” (172-73)

 

What is meant by ‘founded on the imagination’? We can see that imagination is identified with the vivacity of our ideas. Vivacity we saw is the source of our belief in the real existence of something. In this passage we see that Hume says that without the ‘quality’ to form certain ideas in a ‘more intense and lively manner’ or the faculty of enlivening certain ideas beyond others we could never go beyond the purview of the senses which are restricted to the here and now which depends on the ability to attribute existence to something other than the succession of perceptions. So imagination is that faculty that reflects on the activity of consciousness which is the feeling of vivacity and facility felt due to transition from one perception to another in a succession, which feelings are noticed by imagination and taken up within ‘reflected thought’ or imagination or what consciousness is for Hume, and it thereby separates and combines perceptions in accordance with the facility feeling and enlivens ideas not present to the senses and which lead to the formation of a habit to relate one idea with another because it pleases the mind (in accordance with facility feeling) to pass from one to another and this transition becomes inferential i.e. one idea is seen as the reason to posit another because the presence of one idea to consciousness leads to expecting another with the same or almost the same degree of vivacity with which the one is present to the senses and hence one existent is seen as the reason to posit the existence of the other. This habit of expecting one relatum on perceiving another is what becomes a custom and leads to experience which further becomes a means to forge still more relations on the basis of education and culture. Memory is seen by Hume to be a species of imagination (Waxman 1994: 63-66) because it is an enlivened idea dependent on the foundation of ideas on impressions i.e. memory is recollection of a past event when it was actually experienced together with the thought that it was experienced before and so it depends on enlivening of an idea on the basis of a past impression. So memory has a two-fold character, first it is the recollection of a past impression and the reflexive consideration or the mental action of contemplating the appearance of the idea when it was present to the mind. So the idea together with the attendant feeling is what allows memory to relate an idea to a past impression and so to recollect the past. The senses are founded on imagination in a two-fold way, first sight and touch provide us with two incommensurable contents which are combined within a single perception (or a single sense-divide transcending object) which is possible only when imagination combined them together and enlivens the idea of touch when the object is seen and vica-versa and secondly, the objects of sense are seen as mind-independent since they have a continuous existence even when unperceived. This depends imagination’s forming the conceptions of identity and causation i.e. seeing objective understanding to be founded on imagination.

 

We have seen Hume’s psychological principles, now we need to consider the constraints on the content of thought. The primary constraint is what has been called the Copy Principle:

 

“Ideas always represent the objects or impressions, from which they are deriv’d, and can never without a fiction represent or be apply’d to any other.” (30)

 

On the basis of this principle Hume demands that the possession of an Idea must be justified by an appeal to an impression, most importantly to a primal impression. The importance of the primary impression in this case is that the impression is that which is actually present to consciousness. To be actually present to consciousness implies that there is no movement or transition of consciousness that obscures the view of what is really present to us. To attend to the primal impression is like putting an object under a microscope to attend closely to its features through the magnifying effect of the glass; features that are obscured within our ordinary vision; similarly our everyday life consciousness hides certain transitions of thought from our attentive gaze. Hume did not mean that the impression is something which we can selectively attend to since the habits of the mind are so strongly entrenched that some movement of thought will obscure it. But the notion of a primal impression is important to us in order to see whether a notion we have formed is simply a habit of the mind or is truly one possessing an objective validity since it originates from the impression itself. We are ontologically committed only to those entities of which consciousness is truly aware of and whose origin as a consequence lies within the primal impression itself and not to any movement of thought:

 

“’Tis impossible to reason justly, without understanding perfectly the idea concerning which we reason; and ’tis impossible perfectly to understand any idea, without tracing it up to its origin, and examining that primary impression, from which it arises. The examination of the impression bestows a clearness on the idea; and the examination of the idea bestows a like clearness on all our reasoning. (THN 53)”

 

We can see the importance of primal impression in Hume’s psychology when we consider that the only real thing present to the mind is a perception and its comprehension by the senses is restricted to the immediate present. This is the only positive conception we have and what is not sensed involves a reasoning so to say, a movement that goes beyond the senses and this is as we saw due to idea-enlivening imagination which is the source of all relations and all movements of thought. Clearly in a single impression we can never perceive the relation of cause and effect and the continued existence of mind-independent objects and so we have no positive conception of these consequently these ideas are taken to be formed by imagination, which is the source of all Ideas which previous philosophers believed to lie within reason.

 

So the psychological explication of content depends on tracing the origin of the idea back to the primal impression since Ideas represent impressions. But why believe they do? Hume appeals to resemblance (8) in this matter, which relation is constituted by facility feeling and vivacity. Hume justifies this resemblance inductively:

 

“I perceive, therefore, that tho’ there is in general a great resemblance betwixt our complex impressions and ideas, yet the rule is not universally true, that they are exact copies of each other. We may next consider how the case stands with our simple perceptions. After the most accurate examination, of which I am capable, I venture to affirm, that the rule here holds without any exception, and that every simple idea has a simple impression, which resembles it; and every simple impression a correspondent idea. That idea of red, which we form in the dark, and that impression, which strikes our eyes in sun-shine, differ only in degree, not in nature. That the case is the same with all our simple impressions and ideas, ’tis impossible to prove by a particular enumeration of them. Every one may satisfy himself in this point by running over as many as he pleases. But if any one shou’d deny this universal resemblance, I know no way of convincing him, but by desiring him to show a simple impression, that has not a correspondent idea, or a simple idea, that has not a correspondent impression. If he does not answer this challenge, as ’tis certain he cannot, we may from his silence and our own observation establish our conclusion.”

 

Hume also needs to justify that complex ideas refer back to simple impressions and simple ideas:

 

“There is another division of our perceptions, which it will be convenient to observe, and which extends itself both to our impressions and ideas. This division is into SIMPLE and COMPLEX Simple perceptions or impressions and ideas are such as admit of no distinction nor separation. The complex are the contrary to these, and may be distinguish’d into parts. Tho’ a particular colour, taste, and smell are qualities all united together in this apple, ’tis easy to perceive they are not the same, but are at least distinguishable from each other.”

 

Hume uses the notions of parts and our ability to distinguish parts to divide simple and complex perceptions or impressions and ideas. If however we cannot distinguish any parts we can infer that the idea is simple. So Waxman (2005: 409-12) seems correct to understand simplicity as relative to our existing stock of perceptions. This is also supported by the fact that Hume regarded along with Locke that a tactual impression is without parts (152). Further we can also attribute to Hume the Separability Principle based on these passages and his endorsement of Berkeley’s critique of general ideas of Locke:

 

“A very material question has been started concerning abstract or general ideas, whether they be general or particular in the mind’s conception of them? A great philosopher has disputed the receiv’d opinion in this particular, and has asserted, that all general ideas are nothing but particular ones, annex’d to a certain term, which gives them a more extensive signification, and makes them recall upon occasion other individuals, which are similar to them.” (17)

 

“’Tis a principle generally receiv’d in philosophy, that everything in nature is individual, and that ’tis utterly absurd to suppose a triangle really existent, which has no precise proportion of sides and angles. If this therefore be absurd in fact and reality, it must also be absurd in idea; since nothing of which we can form a clear and distinct idea is absurd and impossible. But to form the idea of an object, and to form an idea simply is the same thing; the reference of the idea to an object being an extraneous denomination, of which in itself it bears no mark or character. Now as ’tis impossible to form an idea of an object, that is possest of quantity and quality, and yet is possest of no precise degree of either; it follows, that there is an equal impossibility of forming an idea, that is not limited and confin’d in both these particulars. Abstract ideas are therefore in themselves individual, however they may become general in their representation. The image in the mind is only that of a particular object, tho’ the application of it in our reasoning be the same, as if it were universal.” (18)

 

Hume’s formulation of the Separability Principle in this way:

 

“We have observ’d, that whatever objects are different are distinguishable, and that whatever objects are distinguishable are separable by the thought and imagination. And we may here add, that these propositions are equally true in the inverse, and that whatever objects are separable are also distinguishable, and that whatever objects are distinguishable are also different. For how is it possible we can separate what is not distinguishable, or distinguish what is not different? In order therefore to know, whether abstraction implies a separation, we need only consider it in this view, and examine, whether all the circumstances, which we abstract from in our general ideas, be such as are distinguishable and different from those, which we retain as essential parts of them. But ’tis evident at first sight, that the precise length of a line is not different nor distinguishable from the line itself; nor the precise degree of any quality from the quality. These ideas, therefore, admit no more of separation than they do of distinction and difference. They are consequently conjoin’d with each other in the conception; and the general idea of a line, notwithstanding all our abstractions and refinements, has in its appearance in the mind a precise degree of quantity and quality; however it may be made to represent others, which have different degrees of both.” (17-18)

 

So there are two tests on the content of a thought, first it must be traced back to its source in the impression because ideas are the copies of impressions and resemble them and so refer back to them and second, test is about complex ideas which are formed out of simpler parts different from one another and these parts must be distinguishable and separable by imagination and finally all these simpler parts must be traced back to their primal impression from where alone imagination could have picked them up for the purpose of forming more complex ideas.

 

Apart from complex ideas there are also impressions of reflection to factor in. These are important because Hume reduces the concept of cause and effect to impressions of reflection and not to complex ideas:

 

“Impressions may be divided into two kinds, those of SENSATION and those of REFLECTION. The first kind arises in the soul originally, from unknown causes. The second is deriv’d in a great measure from our ideas, and that in the following order. An impression first strikes upon the senses, and makes us perceive heat or cold, thirst or hunger, pleasure or pain of some kind or other. Of this impression there is a copy taken by the mind, which remains after the impression ceases; and this we call an idea. This idea of pleasure or pain, when it returns upon the soul, produces the new impressions of desire and aversion, hope and fear, which may properly be call’d impressions of reflection because deriv’d from it. These again are copy’d by the memory and imagination, and become ideas; which perhaps in their turn give rise to other impressions and ideas. So that the impressions of reflection are only antecedent to their correspondent ideas; but posterior to those of sensation, and deriv’d from them.”

 

Waxman (1994: 189) finds nine criteria for an impression of reflection: (i) originality: their content must be underived. In Locke and Berkeley we saw the division of ideas of sensation and reflection and that the division was sustainable only if sensations were taken to represent an external reality. Neither Berkeley nor Hume entertain this difficulty but the data from reflection is important for both of them. Berkeley we saw took action and passion to be inseparable within a single consciousness wrongly separated by mind’s abstractive activities but reflection still was the source of the idea of causality for Berkeley since sensation is purely passive and the idea of causality involves an active bringing about something. Locke also derived the idea from reflection over volition which he treated as a simple idea of sense and hence objectively valid. Unlike both Berkeley and Locke, Hume does not attribute objective validity to idea of causality because it is entirely due to associative activity of imagination. However he does not reduce the notion of causality to simple impressions, simple or complex ideas but to an impression of reflection, the inner awareness of a mental act. The reason for this will become clearer below in Hume’s psychological explication of the idea of causality, (ii) affection or the impression of reflection must be a feeling, (iii) it must arise through contemplation of ideas, (iv) must be observable, (v) a source of new ideas, (vi) must have no parts, (vii) admit of total union (viii) possess the utmost degree of force or vivacity and (ix) must be distinct and independent.

 

The inductive justification of the copy principle implies that the principle is also based on habit formed by an idea-enlivening imagination, the constant conjunction of ideas and impressions is so frequent as to lead imagination to trace the origin of content of one back to the other and so to see the impression as the reason or foundation of the idea. This leads to the worry of circularity, the concept of cause-effect is being used to justify psychological explication of the same concept. Waxman (2005: 417) formulates the objection in this way:

 

“Hume’s reliance on the copy principle to explain the origin of ideas raises a specter of circularity that needs to be dealt with right from the outset. For the principle posits a causal relation between impressions and ideas; so, in using it to trace the idea of cause to an origin in an impression of reflexion original, wasn’t he presupposing the very idea he was supposed to explain? The problem is compounded by the fact that Hume’s theory of ideas involves causal relations at every turn: sensations are copied in ideas of sensation, these in turn produce impressions of reflexion, and these in turn are copied in ideas of reflexion. How can cause and effect be explained by means of an explanatory scheme into which it is already built? We must therefore consider whether the circle is real or only apparent, and if real, whether it is vicious or virtuous.”

 

Many recent commentators following N.K. Smith believe that Hume was not much of a sceptic and he did believe that causality was an objectively valid and mind-independent feature of reality or in other words Hume was really Locke in disguise. Waxman (2005: 417-422) gives to my mind adequate reasons to reject this interpretation but even if they are right, Hume becomes less interesting and since he has nothing more important to say about the problem of objective validity, the New Hume becomes redundant for us. So we need to see how Waxman resolves the charge of circularity. He too admits the charge that there is a circularity but denies that it is vicious, rather it is a virtuous one:

 

“The circle would be vicious if and only if the causal relations between impressions and their resembling ideas affirmed in the copy principle were incompatible with the meaning and scope of application of the idea of cause and effect. Since, according to Hume, the idea of cause and effect is bound up by content with customary association—easy, idea-enlivening transitions of thought—the causal relations enshrined in the copy principle would be incompatible with this idea only if the principle is premised as being prior to and independent of customary association. Thus, the question whether or not Hume’s copy principle is viciously circular can be answered by determining whether or not it is associative in nature.” (Waxman 2005: 423)

 

“The only way this could fail to issue in a vicious circle is if none of these elements of the causal explanation of impressions of necessary connections enter into the content of the impression of necessary connection itself. Do they? It seems not. For if one is careful to distinguish the contents Hume actually ascribed to the impression from the details of his account of its origin, there are only the following: (i) a transition of thought, (ii) a feeling of ease in the transition, and, (iii) when the transition is from an impression to an idea, (iv) the idea is regarded in imagination with a feeling of force and vivacity (belief) that approaches the vivacity with which impressions are regarded pre-imaginatively.

 

Everything else in Hume’s account of cause and effect—the memory caused by the experience of constant conjunction, the customs of thought caused by the memory, and the transitions of thought caused by the customs—relates not to the content of the idea but to its causal explanation, that is, the application of this idea to its own origin. But since these causal relations fall outside the content of the idea, the circle they describe is not vicious: having an idea of necessary connection distinct in content from the ideas of past experience and habit, we are free to utilize this idea both in the conception of experience (as the cause of customs) and habit (construed as a cause of facile transitions) themselves and to relate them to reflexive impressions of necessary connection as cause and effect. This is true even of the copy relation that binds our ideas of necessary connections to these impressions itself: since its content consists merely in facile transitions from the impressions to the temporally contiguous ideas reinforced by the addition of a relation of almost perfect resemblance between them, we are free to invoke experience and habit as the cause both of the presence of this content in our mind (its origin) and of the unsurpassed strength of its influence on our reasoning (because the habit is founded on perhaps the most constant and continuously recurrent conjunction in human experience). Thus, as a matter simple and solely of relations whose essence consists in facile transitions of thought, or at least are founded on such transitions, the circularity implicit in Hume’s solution to the problem of origins reveals itself to be impeccably virtuous.” (Waxman 2005: 444-45)

 

Waxman’s answer depends on distinguishing between philosophical and natural relations. The content of the concept of causality is really determined by the latter – easy facile transitions between impressions to ideas and an idea-enlivening imagination that determines an unknown object with an equivalent force and vivacity of the known or the present object. Custom or habit and memory of constant conjunction we saw are left outside the content of the concept and figure in the psychological mechanism rather than the psychologistic content of thought. To examine this answer on Hume’s behalf we need to examine Hume’s reduction of the concept of cause to an impression of reflection which is constituted solely by feelings.

In his Treatise (114) Hume offers two definitions of cause-effect:

 

“There may two definitions be given of this relation, which are only different, by their presenting a different view of the same object, and making us consider it either as a philosophical or as a natural relation; either as a comparison of two ideas, or as an association betwixt them.

 

We may define a CAUSE to be “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.” If this definition be esteem’d defective, because drawn from objects foreign to the cause, we may substitute this other definition in its place, viz.

 

“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.”

 

In justification of the definitions Hume says:

 

“When I examine with the utmost accuracy those objects, which are commonly denominated causes and effects, I find, in considering a single instance, that the one object is precedent and contiguous to the other; and in enlarging my view to consider several instances, I find only, that like objects are constantly plac’d in like relations of succession and contiguity. Again, when I consider the influence of this constant conjunction, I perceive, that such a relation can never be an object of reasoning, and can never operate upon the mind, but by means of custom, which determines the imagination to make a transition from the idea of one object to that of its usual attendant, and from the impression of one to a more lively idea of the other.” (114-115)

 

Hume considers the definition of cause-effect relation as either a philosophical relation or a natural relation, the difference between the two he points out is a difference between comparing ideas and compared ideas which is what he most probably means by ‘as an association betwixt them’. The difference is in one case an idea of relation seems to be formed after a subject compares two and in another case two ideas are already found to be related to each other. But more clarity is needed here, is the idea of relation formed on comparison, an objective relation between compared objects or is the relation a subjective one that is yet formed on comparing objects or is the relation constituted by the comparison itself? The first is against the entire logic of the psychologism project, the second and the third option are different in this that in the former an idea of relation is formed post comparing different objects together but by the copy principle, the idea must represent an impression and relations are not the objects of impression, fleeting perceptions are. In the latter option the essence of the relation is the comparison, the activity of separating and combining idea itself and there is no idea of relation at all. But if there is no idea of relation that is different from natural relation constituted by facility feeling and vivacity then the distinction between philosophical and natural relation is obliterated (Green 1894: sec.296-297).

 

Now let us consider how causation can be defined in terms of a natural relation or an impression of reflection. It may well be noticed that both the definitions begin with defining cause as an object which stands in relation of spatial-temporal contiguity which allows the mind on the basis of previous experiences to determine the existence of one from the other. Causal relation is seen as a relation between objects yet the content of an impression of reflection is not an object but the succession of feelings. Waxman (1994: 187-188) feels the pressure of this problem:

 

“However, Hume's identification of the necessity impression with feelings of ease of transition and vivacity poses a problem, since he never elsewhere characterized these feelings as impressions. An impression is a perception and as such, by the separability principle, is capable of existing in consciousness on its own, distinct from every other. Yet, it is the very essence of Hume's theory of belief that vivacity be neither an independent perception which the imagination might then arbitrarily conjoin to any perception whatever nor something distinguishable from a perception only abstractly, as an. So, too, the feeling of ease characteristic of custom: it must be felt in the transition from one perception to another and so obviously cannot exist apart from them, as a distinct perception in isolation from all others. Since Hume's text is quite clear that the impression-original of necessity is composed solely and entirely of these feelings, we must either convict him of inconsistency or suppose him to have had in mind the entire complex consisting of (i) the impression, (ii) its idea associate, (iii) the consciousness of their succession, and (iv) the feelings characterizing this consciousness. Yet, it would be odd to characterize this whole as a reflexive impression; these impressions are in theory distinct from the ideas that cause them, and so should, like any other genuine perception, admit of standing alone before consciousness.”

 

The problem is feelings are instable and fleeting like the succession of perceptions that affect us, by the time we could even demonstratively point out to them they would have passed and so clearly they are unsuitable to be content of a concept and yet a whole host of it is part of impression of reflection. Yet Waxman is confident that the difficulty can be assuaged:

 

“…..the question then is whether it should be regarded as a major lapse fatal to his system or merely a misdemeanor? In light of the considerations above, I am inclined to the latter view. For the main requirements of Hume's account of necessary connection are to (i) derive the idea from repeated experience (i.e. the impression of reflexion in which "similar views run into each other, and unite their forces, (ii) trace it to a source which sets its non-rational nature beyond all doubt, and (iii) explain why necessity is always believed to lie in the objects and not our thought. These goals he achieved by identifying its "impression" original with the feelings of easy transition and vivacity/verisimilitude. In reasoning about, recalling, or imagining necessary connections, we are merely reproducing a reflexive image instinctively formed in imagination. This image consists entirely of feelings occasioned by previous observations, and is no more rational in nature than fear, desire, and other (authentic) reflexive impressions.” (Waxman 1994: 190)

 

And at the end of this passage Waxman reiterates the distinction between psychological mechanism and psychological content:

 

“As exhibited here, the complex idea of necessary connection is entirely phenomenological. Everything for which experience is requisite - viz. remembered constant precedence and custom qua inclination or propensity (rather than as a feeling) - proves to be external to the idea, part of its causal explanation rather than of its content. Nothing actually constitutive of that idea needs to be, or even can be, given in experience (viz. the feelings of facility and vivacity characteristic of the transition from impression to idea plus the perceived temporal precedence of the cause-perception vis a vis the effect-perception). Its contents are one and all objects of immediate consciousness, immanent to associative imagination.” (Waxman 1994: 190).

 

Waxman leaves out memory of constant conjunction as a circumstance under which we may come by the idea of a cause and that the memory of constant precedence is not requisite to possess the necessity impression and yet he himself points out that the idea or the impression reflection has to be derived from repeated experience which has to involve memory. The idea cannot be derived from a single impression but a succession of impressions conjoined within thought or imagination. The psychological explication of the concept of causation depends on showing that it is derived from an impression and necessarily refers back to it. The relevant impression or impressions in this case are the feelings of facility and vivacity imagination feels in passing over one perception to another and registering that feeling within consciousness to form an impression of reflection. The same feeling contemplated within primal impression is taken over to form an impression of reflection and no new content is formed. Waxman accepts that ‘nothing constitutive of the idea is to be given in experience’ and that vivacity and facility feeling are ‘objects of immediate consciousness immanent to associative imagination’, but what is given to us an object of experience? “….that the one object is precedent and contiguous to the other; and in enlarging my view to consider several instances, I find only, that like objects are constantly plac’d in like relations of succession and contiguity.” Notice that causation is supposed to be a relation (THN 52-53) that takes us beyond what is immediately present to consciousness and yet the content of the concept is determined solely by those feelings that are objects of immediate consciousness.

 

So on the one hand the scope of application of the concept has to be delimited to consciousness by tracing the concept back to its origins within an impression or what is immediately present to consciousness while on the other hand the concept of cause allows us to move beyond what is simply present to consciousness which transition is seen as nothing but those constitutive feelings which remain the immediate objects of consciousness immanent to associative imagination.

 

But Waxman may retort at this stage that what he calls the ‘projective illusion’ or the propensity to feign is what allows causation to extent our purview from immediate datum of senses to what is beyond it and attribute causation to an external object instead of consciousness where the concept truly resides:

 

“’Tis a common observation that the mind has a great propensity to spread itself on external objects, and to conjoin with them any internal impressions, which they occasion, and which always make their appearance at the same time that these objects discover themselves to the senses. . . . The same propensity is the reason, why we suppose necessity and power to lie in the objects we consider, not in our mind, that considers them; notwithstanding it is not possible for us to form the most distant idea of that quality, when it is not taken for the determination of the mind, to pass from the idea of an object to that of its usual attendant.” (112-113)

 

It is because of this propensity to feign that we attribute causality to objects and explain the existence of one object by referring to another instead of expecting a sequence of feelings and so it turn out that the concept of cause is feigned and hence fictional or a fancy, lacking in objective validity. The mind never really goes beyond perception which is the only object of consciousness. It is the ‘affective disposition’, of imagination that by momentum as it were it carries mind beyond its usual object by feigning that another object exists:

 

“’twill readily be allow’d, that since nothing is ever really present to the mind, besides its own perceptions ’tis not only impossible, that any habit shou’d ever be acquir’d otherwise than by the regular succession of these perceptions, but also that any habit shou’d ever exceed that degree of regularity. Any degree, therefore, of regularity in our perceptions, can never be a foundation for us to infer a greater degree of regularity in some objects, which are not perceiv’d; since this supposes a contradiction, viz. a habit acquir’d by what was never

present to the mind. But ’tis evident, that whenever we infer the continu’d existence of the objects of sense from their coherence, and the frequency of their union, ’tis in order to bestow on the objects a greater regularity than what is observ’d in our mere perceptions.” (131-132)

 

“We may observe, that the supposition, that the future resembles the past, is not founded on arguments of any kind, but is deriv’d entirely from habit, by which we are determin’d to expect for the future the same train of objects, to which we have been accustom’d. This habit or determination to transfer the past to the future is full and perfect; and consequently the first impulse of the imagination in this species of reasoning is endow’d with the same qualities.” (92)

 

The relation of cause and effect is an invariable and necessary relation between two objects. I see smoke to be always present where there is fire and note that fire is temporally precedent to smoke. Seeing them together with no counter-example in sight, mind passes from one to the other and believes in the existence of one from the existence of the other. But the relation is not found between the particular smoke and the particular fire, rather the relation holds for any particular smoke and any particular fire even if there is no universal smoke-ness or fire-ness. The causal relation between smoke and fire for example, has to be seen as an instance of a law which stands over and above particulars and which applies to each and every particular. This is also how Hume saw causation, this feature is what for him distinguishes causal relation from spatial and temporal contiguity:

 

“’Tis evident, that whatever is present to the memory, striking upon the mind with a vivacity, which resembles an immediate impression, must become of considerable moment in all the operations of the mind, and must easily distinguish itself above the mere fictions of the imagination. Of these impressions or ideas of the memory we form a kind of system, comprehending whatever we remember to have been

present, either to our internal perception or senses; and every particular of that system, join’d to the present impressions, we are pleas’d to call a reality. But the mind stops not here. For finding, that with this system of perceptions, there is another connected by custom, or if you will, by the relation of cause or effect, it proceeds to the consideration of their ideas; and as it feels that ’tis in a manner necessarily determin’d to view these particular ideas, and that the custom or relation, by which it is determin’d, admits not of the least change, it forms them into a new system, which it likewise dignifies with the title of realities. The first of these systems is the object of the memory and senses; the second of the judgment.” (75)

 

“But tho’ I cannot altogether exclude the relations of resemblance and contiguity from operating on the fancy in this manner, ’tis observable that, when single, their influence is very feeble and uncertain. As the relation of cause and effect is requisite to perswade us of any real existence, so is this perswasion requisite to give force to these other relations. For where upon the appearance of an impression we not only feign another object, but likewise arbitrarily, and of our mere good-will and pleasure give it a particular relation to the impression,

this can have but a small effect upon the mind; nor is there any reason, why, upon the return of the same impression, we shou’d be determin’d to place the same object in the same relation to it. There is no manner of necessity for the mind to feign any resembling and contiguous objects; and if it feigns such, there is as little necessity for it always to confine itself to the same, without any difference or variation. And indeed such a fiction is founded on so little reason, that

nothing but pure caprice can determine the mind to form it; and that principle being fluctuating and uncertain, ’tis impossible it can ever operate with any considerable degree of force and constancy.” (76)

 

To borrow Green’s example, the picture of a person is taken to represent that person but this resemblance is not taken to be a causal relation because the idea of the person is brought to the mind by our good pleasure or pure caprice. With contiguity and resemblance relations we cannot have a ‘system of realities’ which Hume divides into ‘system of memory’ and ‘system of judgement’. The point to emphasize is that within a causal network, the ascription of causality depends on a system of realities. As Waxman points out the invariable relation between a cause and effect is not an autobiographical prediction, it is not the case that in my experience smoke and fire have been found in constant conjunction and so they will be found to be conjoined in my future experiences. The causal law holds for everyone, independently as it were of what our experiences may be and only then is the causal relation between two entities seen to be real since they belong to a system of reality. A projective illusion may be necessary to take us beyond the immediacy of sensible experience to an unknown object which is only feigned to exist but this feigning will not fetch us a sense of reality till it becomes a part of the system of reality. Projective illusion can explain the split within consciousness of subject and object, but the object has to be seen as governed by laws that are independent of the subject and which laws are responsible for uniformity of experience itself. Hume is aware of this and so he invokes the uniformity principle, in ECHU 4.2.16 Hume distinguishes three questions: 1. What is the nature of reasoning concerning all matters of fact? The answer he gives is cause and effect, 2. What is the foundation of all our reasoning and conclusions concerning that relation? Experience 3. What is the foundation of all conclusions from experience? This he believes is a different and a difficult question to answer because:

 

“Sight or feeling conveys an idea of the actual motion of bodies; but as to that wonderful force or power, which would carry on a moving body for ever in a continued change of place, and which bodies never lose but by communicating it to others; of this we cannot form the most distant conception. But notwithstanding this ignorance of natural powers and principles, we always presume, when we see like sensible qualities, that they have like secret powers, and expect, that effects, similar to those which we have experienced, will follow from them. If a body of like colour and consistence with that bread, which we have formerly eat, be presented to us, we make no scruple of repeating the experiment, and foresee, with certainty, like nourishment and support. Now this is a process of the mind or thought, of which I would willingly know the foundation.”

 

“As to past Experience, it can be allowed to give direct and certain information of those precise objects only, and that precise period of time, which fell under its cognizance: But why this experience should be extended to future times, and to other objects, which for aught we know, may be only in appearance similar; this is the main question on which I would insist.”

 

From my experience that like effects have like causes, I infer that similar objects will always be attended with similar effects. Hume acknowledges that in this transition there seems to be a ‘certain step taken, a process of thought, an inference which wants to be explained’, but then he challenges his interlocutor to produce that chain of reasoning that allows us to make that transition from is to must always:

 

“Now where is that process of reasoning, which, from one instance, draws a conclusion, so different from that which it infers from a hundred instances that are nowise different from that single one? This question I propose as much for the sake of information, as with an intention of raising difficulties. I cannot find, I cannot imagine any such reasoning.” (ECHU 4.2.20)

 

No matter how many times we may have observed two objects together, that does not allow us to infer that in every case they will always be found together:

 

“It is impossible, therefore, that any arguments from experience can prove this resemblance of the past to the future; since all these arguments are founded on the supposition of that resemblance.” (ECHU 4.2.21)

 

“We have said, that all arguments concerning existence are founded on the relation of cause and effect; that our knowledge of that relation is derived entirely from experience; and that all our experimental conclusions proceed upon the supposition, that the future will be conformable to the past.” (4.2.19)

 

This particular passage is really strange because on the one hand Hume is confessing that from experience we can never form the conceptions of necessity and universality that determine the uniformity of experience, that all reasoning concerning the existence of something is founded on the relation of cause and effect and yet we cannot infer that the future will be conformable to the past. The reason is that the uniformity principle is based on a ‘process of thought’, not dependent on the relation of cause and effect, there is an extra step that the mind seems to take and hence the content of the uniformity principle is distinct from the content of the impression of necessity. He argues that his fellow rationalist philosophers too cannot account for what reasoning allows them to move from observed to unobserved cases and so the only solution of the problem in sight is that even though it seems a certain additional step has been taken, actually none has been taken:

 

“It is certain, that the most ignorant and stupid peasants, nay infants, nay even brute beasts, improve by experience, and learn the qualities of natural objects, by observing the effects, which result from them. When a child has felt the sensation of pain from touching the flame of a candle, he will be careful not to put his hand near any candle; but will expect a similar effect from a cause, which is similar in its sensible qualities and appearance. If you assert, therefore, that the understanding of the child is led into this conclusion by any process of argument or ratiocination, I may justly require you to produce that argument; nor have you any pretence to refuse so equitable a demand.” (ECHU 4.2.23)

 

This in essence is Hume’s solution to the problem of induction that he himself raises. Has the content of the uniformity principle been reduced to the content of the necessity impression? Is uniformity too nothing but inferring one thing to exist on noticing the existence of another? But there seems to be more involved in reasoning about cause and effect. The cause has to be seen as the reason for the existence of the effect, whose existence calls out to be explained and whose explanation consists in citing the cause. The relation of cause-effect has that explanatory power because it is grounded in uniformity of nature and not subjective reasoning which only leads the mind to pass from the existence of one object to the existence of other. This transition cannot be called reasoning or inferring unless the existence of one justifies the existence of the other or is the reason why something else exists. This is implicit in the definition of cause Hume has given, cited above and also in ECHU 7.2.29:

 

“Similar objects are always conjoined with similar. Of this we have experience. Suitably to this experience, therefore, we may define a cause to be an object, followed by another, and where all the objects, similar to the first, are followed by objects similar to the second. Or in other words, where, if the first object had not been, the second never had existed.”

 

Note that from the second line where similar causes are followed by similar effects, in the third line Hume infers or rather considers as equivalent the formulation that if one had not been, the second would never have existed. But neither are the two propositions equivalent nor does one follow from the other because as Hume himself points out there is a certain step missing. The content of the necessity impression is formed out of (i) transitions of successive mental states (ii) feelings of facility and vivacity felt in that transition and (iii) imagination reflecting on these transitions to ‘transpose and change ideas’ (12) whose order and position need not be conserved by imagination, in order to enliven ideas with a vivacity less than found within immediacy of consciousness but enough to consider the idea as real as the impression preceding it is. So the content of necessity comes to this that a constant conjunction leads to future expectation and enlivening of an idea on the basis of its corresponding impression. This is how the copy principle itself is justified. All ideas represent or refer back to their impressions because their conjunction has been noticed so many times that imagination begins to enliven the idea on the basis of the presence of the impression. But the copy principle if it is to effect a psychologistic reduction of a concept must contain more than passing from existence of impression to idea, the idea must be seen as grounded within the impression which is to be considered as the reason why the idea has the content it does. In ordinary experience we cite the impression or the perception of a tree is cited as the reason why I believe that there is a tree in front of me. Now Waxman (2005: 539) himself points out that Hume’s major insight was to reduce the epistemological question of justification to the psychological question of origins of a concept:

 

“…..Hume’s principal motivations for making the task of tracing ideas of necessary connection to their originating impression his top priority was to gain insight into the nature of empirical reason (also termed by him “probable reason,” “moral reason,” and “experimental reason”).

For evidence in any reasoning relating to matters of fact and real existence must consist, first and foremost, of evidence for the existence of a necessary connection between the distinct existents invariably involved in such reasoning; and the only source from which such evidence can be derived are the impressions of reflexion from which our ideas of necessary connection all originate. Thus did Hume come to see the essential oneness of two issues that philosophers, then as now, tend to think of as distinct: the epistemological question of what evidence justifies us in drawing a conclusion regarding matters of fact and real existence, and the psychological question of the source from which ideas of necessary connections between distinct existents originate.”

 

In order to merge the epistemological question with the psychological question Hume has to show that the content of ‘must’ and ‘always’ or necessity and uniformity must coincide too. But in the psychological realm the content of the concept is - similar objects will be followed due to psychological laws by similar objects where ‘followed by’ really means the determination of mind to pass from one object to another due to feelings of facility and which leads to enlivening an idea. But the epistemological content of the concept is if one exists, the other must exist too and hence the existence of one is the reason why the other exists. Hume is more than happy to turn the tables on the rationalist since they cannot explain what piece of reasoning allows one to move rationally from observed to unobserved cases. But the rationalist too can turn the tables on Hume since uniformity of cause and effect involves a conception of necessity and universality that is not captured in the psychological reduction of the concept of cause to its psychological origins and also Hume cannot insist that the rationalist must justify his belief in the uniformity principle on the basis of experience only. In order to do so he must show that ideas are not simply preceded by impressions but necessarily the content of the one must be derived from the other or in other words the reason why an idea has a certain content must be due to the impression. If such necessity is not in place then the route lies open to involve a distinct source of knowledge to explain the content of an idea since no strong relation of dependence between the impression and the idea exists in Hume’s psychology. On the one hand we saw Hume contend that no experiential reasoning can justify uniformity principle because the principle is what determines the reasonableness and the rationality of an argument and so any such attempt will be circular (ECHU 4.2.19 and Waxman 1994: 157-159). But that depends on seeing uniformity principle as setting the standard for rationality for which Hume gives no justification except that we are used to move from the existence of one to the other in accordance with nature’s ingrained psychological laws. So either these psychological laws determine the content of ‘reason’ or else Hume has to accept that he is not able to capture that content at all; either we have a psychological reduction or we don’t. Moreover it can be said that Hume was wrong to separate the question of nature of reasoning and the conclusions from foundation of reasoning. The nature of reasoning or the relation which involves movement from one object to another is the relation of cause and effect. But the conclusion derived about unobserved cases are not related by this relation because it is a subjective determination. But if the cause-effect relation is not determined by uniformity of causes and effects then it cannot constitute the nature of reasoning and cannot make experience the foundation of reasoning. It is a transition of thought that does not allow transfer of justification or seeing one as the reason of the existence of other which is the essence of reasoning. So the answer to the third question cannot be separated with the answer of the first and the second question. This point can be made using an observation Hume made later in his philosophy but which makes always makes its presence felt in his philosophy. Hume believes that probable or empirical reason cannot justify the uniformity principle since the justification would be circular, it is uniformity that is the paradigm of rationality and so from this reasoning we see that Hume is deriving empirical reason from a normative principle and hence uniformity principle must exceed the content of psychological transitions or we have an is-ought fallacy. Hume cannot derive an ‘ought’ from an ‘is’ without incurring the charge of circularity, so the concept of cause cannot be derived from certain psychological transitions because that would not explain why the cause is seen as the reason of the existence of the effect. Hume needs to explain how a normative epistemological framework is derived from psychological transitions but he has shown that the uniformity principle cannot be derived from his psychology. The extra step that is missing is the one that is needed to convert the ‘is’ to an ‘ought’. Hume feels the pressure but the solution he arrives at (ECHU 4.2.23 quoted above) is that we need to be content with the ‘is’ but then the psychological explication of the concept of cause fails because the content of the concept has not been psychologized without a remainder. This means that the causal relation will be seen as an ‘autobiographical prediction’ and not a uniform relation or a result of a law or harmony in nature. The gap between the two is the gap between is and ought which Hume’s psychology does not bridge. Causality is Hume’s key to taking consciousness outside the immediate datum of consciousness, even by feigning so. But causality can accomplish this task not qua a fiction but only if the content of the concept is determined by a uniformity principle and not an impression of reflection.

 

Also the operations of imagination itself depends on uniformity since it abstracts from concrete flux of feelings felt in transition of perceptions to forge a new order and connection which is necessary for justification and which we saw what Hume refers to as the ‘system of memory’ because the system of realities is connected through a uniformity principle without which the copy principle cannot be justified:

 

“Of these impressions or ideas of the memory we form a kind of system, comprehending whatever we remember to have been present, either to our internal perception or senses; and every particular of that system, join’d to the present impressions, we are pleas’d to call a reality.” (75)

 

Waxman (2005: 440) regards this ‘system of memory’ as an expository tactic and this is what allows him to parry the circularity charge by separating the content of memory and the content of necessity impression. But if the copy principle be regarded as based on natural relation alone then one cannot justify the possession of an idea on the basis of an impression because this justification demands a system of reality that abstracts from the order and position of perceptions and places them within a system where the causal relation between impression to idea is independent of subjective determination from one to the other. This is what imagination is supposed to do or else there would always be a fleeting succession of perceptions and elusive feelings permanently annexed to unstable perceptions. Transfer of vivacity and belief is not possible if the movement is seen as due to ‘pure caprice’. But the impression has to be seen as a reason that justifies the possession of an idea. When Hume asks for the primal impression to justify the possession of a content, the demand’s plausibility consists in the idea’s epistemological relation to the impression and not simply a psychological relation.

 

It is imperative here to understand that the psychologism about the content of thought is plausible only with reduction of the epistemological question to the psychological question of origins. I can for instance restrict the content of the concept of cause to affections felt within consciousness only if the latter constitutes the former or is the essence of the former, which leaves open no possibility (one should recall here Berkeley’s failure to reduce sensible objects to consciousness), that the content of the concept can be derived from a non-sensible source and the preclusion of this possibility demands a necessary relation where the existence of one justifies the existence of the other. This necessity is different from necessity of the association of ideas in an idea-enlivening imagination for the latter necessity does not preclude the possibility of another source creeping in since its really says that like causes are followed by like effects and not that one is not possible without the other. So the dilemma for Waxman is if he excludes ‘system of realities’ from the copy principle to reduce the relation to a natural relation then he or rather his version of Hume, forfeits psychologism of the concept of necessity which demands going back to the primal impression and if he includes a ‘system of realities’ to justify the copy principle then the charge of circularity follows since such a system presupposes uniformity and a necessity whose content is different from the necessity impression but on which depends the possibility of justification. On these grounds I believe that Green’s (1894: sections 328-331) criticism of Hume in his Introduction to Hume is justified.

Hume's Scepticism

For Hume all kinds of reasoning consist in nothing but comparison (52) and following Locke he defined knowledge to lie in agreement or disagreement of ideas we compare which allows us to distinguish between intuitive or demonstrative knowledge and knowledge about matters of fact or existence (ECHU 4.1.1). The former is discoverable “by the mere operation of thought, without dependence on what is anywhere existent in the universe.” And the characteristic trait of the latter kind of knowledge is:

 

“Matters of fact, which are the second objects of human reason, are not ascertained in the same manner; nor is our evidence of their truth, however great, of a like nature with the foregoing. The contrary of every matter of fact is still possible; because it can never imply a contradiction, and is conceived by the mind with the same facility and distinctness, as if ever so conformable to reality. That the sun will not rise to-morrow is no less intelligible a proposition, and implies no more contradiction, than the affirmation, that it will rise. We should in vain, therefore, attempt to demonstrate its falsehood. Were it demonstratively false, it would imply a contradiction, and could never be distinctly conceived by the mind.”

 

These traits are a) contrary of matter of fact is still possible because the contrary does not imply a contradiction and b) it is conceived by the mind to conform to reality. To use Hume’s example (26) the idea of the mountain and valley cannot be separated by the mind; it is impossible to form the idea of one without forming the idea of the other. The necessity by which we cannot conceive the contrary is a necessity that lies within the idea itself not in the comparison of the idea. This gives us two notions of necessity, one due to comparison of ideas themselves and other due to the content of the ideas. Demonstrative knowledge belongs to the latter. Hume’s further innovation was to take arithmetic and geometry to be matter of fact kind of reasoning rather than demonstrative and hence to use more modern terms, mathematics turns out to be synthetic rather than analytic. But Hume’s notion of analyticity is problematic since his system does not explain how or in what sense one content can contain another:

 

“So the question that arises is this: how are necessary relations between distinct ideas possible that cannot be discovered simply by considering (analyzing) the ideas themselves, prior to and independently of the determination of the imagination that results from the act of comparing them? The answer Hume provided in the case of necessary connections between distinct existents—facile transitions of thought founded on conjunctions of perceptions experienced with sufficient frequency and constancy to confer on the idea to which the transition is made a vivacity that approaches an impression—cannot here suffice. For he recognized that this account of necessary relations applies only where intuitive or demonstrative insight is wanting (50, 77, 410). In cases where such insight exists, however, facility and vivacity are irrelevant (THN 66). Yet we search Hume’s writings in vain for even so much as a recognition of the problem, much less an appreciation of how deep it goes or how intractable it is (requiring nothing less than a critique of pure reason for its solution).” (Waxman 2005: 503-504)

 

With this background we come to Hume’s investigation of the necessity of ‘cause’ (56):

 

“Whatever begins to exist, must have a cause of existence.”

 

This proposition is regarded as certain and its contrary is considered to be inconceivable and hence the proposition is necessarily true. Hume’s endeavour is to show that the necessity that pertain to this proposition is a subjective necessity and in order to do so he first has to show that the proposition lacks a demonstrative or analytic necessity:

 

“But here is an argument, which proves at once, that the foregoing proposition is neither intuitively nor demonstrably certain. We can never demonstrate the necessity of a cause to every new existence, or new modification of existence, without showing at the same time the impossibility there is, that anything can ever begin to exist without some productive principle; and where the latter proposition cannot be prov’d, we must despair of ever being able to prove the former. Now that the latter proposition is utterly incapable of a demonstrative proof, we may satisfy ourselves by considering, that as all distinct ideas are separable from each other, and as the ideas of cause and effect are evidently distinct, ’twill be easy for us to conceive any object to be non-existent this moment, and existent the next, without conjoining to it the distinct idea of a cause or productive principle. The separation, therefore, of the idea of a cause from that of a beginning of existence, is plainly possible for the imagination; and consequently the actual separation of these objects is so far possible, that it implies no contradiction nor absurdity; and is therefore incapable of being refuted by any reasoning from mere ideas; without which ’tis impossible to demonstrate the necessity of a cause.” (56)

 

The key in this argument is the separability principle whose clearest statement as we also saw in the previous section is:

 

“We have observ’d, that whatever objects are different are distinguishable, and that whatever objects are distinguishable are separable by the thought and imagination. And we may here add, that these propositions are equally true in the inverse, and that whatever objects are separable are also distinguishable, and that whatever objects are distinguishable are also different. For how is it possible we can separate what is not distinguishable, or distinguish what is not different?” (17)

 

This principle will be called Separability Principle (SP) which says that all objects that are different are distinguishable. Here ‘objects’ and ‘ideas’ are being used interchangeably (21). So different ideas are separable because distinguishable. The implication of this principle will become clear when when we consider an apparent counter-example to SP, the distinction of reasons:

 

“Before I leave this subject I shall employ the same principles to explain that distinction of reason, which is so much talk’d of, and is so little understood, in the schools. Of this kind is the distinction betwixt figure and the body figur’d; motion and the body mov’d. The difficulty of explaining this distinction arises from the principle above-explain’d, that all ideas, which are different, are separable. For it follows from thence, that if the figure be different from the body, their ideas must be separable as well as distinguishable; if they be not different, their ideas can neither be separable nor distinguishable. What then is meant by a distinction of reason, since it implies neither a difference nor separation? To remove this difficulty we must have recourse to the foregoing explication of abstract ideas. ’Tis certain that the mind wou’d never have dream’d of distinguishing a figure from the body figur’d, as being in reality neither distinguishable, nor different, nor separable; did it not observe, that even in this simplicity there might be contain’d many different resemblances and relations. Thus when a globe of white marble is presented, we receive only the impression of a white colour dispos’d in a certain form, nor are we able to separate and distinguish the colour from the form. But observing afterwards a globe of black marble and a cube of white, and comparing them with our former object, we find two separate resemblances, in what formerly seem’d, and really is, perfectly inseparable. After a little more practice of this kind, we begin to distinguish the figure from the colour by a distinction of reason; that is, we consider the figure and colour together, since they are in effect the same and undistinguishable; but still view them in different aspects, according to the resemblances, of which they are susceptible. When we wou’d consider only the figure of the globe of white marble, we form in reality an idea both of the figure and colour, but tacitly carry our eye to its resemblance with the globe of black marble: And in the same manner, when we wou’d consider its colour only, we turn our view to its resemblance with the cube of white marble.” (21-22)

 

So here we have two senses of ‘distinguishability’, in the first sense if the figure was different from the body then their ideas must have been distinguishable and separable. To test this argument Hume uses the example of a globe of white marble. When we receive the impression of such an object we cannot distinguish the colour from the form of the object and only when we compare a globe of white marble with a globe of black mark do we distinguish between colour and shape; we see the two similar in shape but different in colour and this comparison allows us to distinguish and separate the two. So the second sense of distinguishablity depends on the act of comparison and hence ontologically the content of the idea remains the same – what is grasped in the impression, but semantically a difference has been produced depending on the different resemblance relations we consider and so what is the ‘same’ and ‘undistinguishable’ is seen as different and distinguishable. So the SP is really a corollary of the Copy Principle and it is a test to separate semantic from ontological implication of Ideas and impressions, since ontological or objective validity rests with the primal impression.

 

Ontological or objective validity always lies with the simple impression. The difference between figure and colour and motion and the body moved is not an ontological distinction because within the impression we do not discern these differences. But is it possible that there are certain differences within an impression that we do not grasp? Hume applies the appearance = reality principle to impressions and so would deny such a possibility. We cannot separate mountain and a valley and motion and the body moved because the underlying impressions are the same but in the case of cause-effect relation the underlying impressions are distinct and hence the content is distinct ergo no demonstrative relation between the two can be found.

 

Now to come back to Hume’s argument he begins by arguing that we can never demonstrate the necessity of a cause to every new existence without showing that the negation of this principle is impossible. If one cannot show that the negation of the principle is impossible then there is no hope for showing the intuitive and demonstrative necessity of cause-effect relation. As we have seen analytic necessity (and possibility or impossibility of the contrary) is grasped by the mind, due to the content of the ideas and without the interposition of any ideas. Intuitive certainty or analyticity depends on the content of the ideas and Hume’s intention is to deprive the relation of any objective validity. So Hume says that the inference of the existence of one from another is not due to the objects themselves, if it was due to the object themselves then that would constitute knowledge since the impossibility of the negation would be manifest to us but it is not since the idea of cause and effect are distinct (61).

 

So the argument runs as follows:

 

Premise 1. All distinct ideas are separable

 

Premise 2. The idea of cause and effect are distinct

 

By (2) and (3): So we can conceive the existence of one without conceiving the existence of the other, so it is possible that one exists separately from the other

 

Conclusion: Therefore no intuitive or demonstrative necessity can be found between the ideas of cause and effect.

 

The ideas are distinct because the impressions are distinct and the further act of comparison that is used to form the idea involves a temporal order, one preceding the other in constant conjunction. From this Hume believes it is easy to conceive any object non-existent this moment and existent the next without conjoining the idea to a cause or a productive principle. From this Hume infers: “the actual separation of these objects is so far possible.” This inference can be made because the idea of existence is nothing different from the idea or the conception of an object (48) and anything that can be conceived is possible. So it is possible that something begins to exist without a production principle or without a cause.

 

From this conclusion Hume proceeds to find the cause of union of ideas which are different and thereby to ground all reasoning about matters of fact of existence to relation of cause-effect:

 

“Perhaps ’twill appear in the end, that the necessary connexion depends on the inference, instead of the inference’s depending on the necessary connexion.” (62)

The nature of the inference that constitutes necessary connexion Hume tells us is one that satisfies the Separability Principle:

“’Tis easy to observe, that in tracing this relation, the inference we draw from cause to effect, is not deriv’d merely from a survey of these particular objects, and from such a penetration into their essences as may discover the dependence of the one upon the other. There is no object, which implies the existence of any other if we consider these objects in themselves, and never look beyond the ideas which we form of them. Such an inference wou’d amount to knowledge, and wou’d imply the absolute contradiction and impossibility of conceiving anything different. But as all distinct ideas are separable, ’tis evident there can be no impossibility of that kind. When we pass from a present impression to the idea of any object, we might possibly have separated the idea from the impression, and have substituted any other idea in its room. ’Tis therefore by EXPERIENCE only, that we can infer the existence of one object from that of another.” (61)

Subjective necessity rests on transitions of perceptions, facility and vivacity feeling and an idea-enlivening imagination and this is the bond or union by which different ideas are united in our mind. These psychological principles of union among ideas must be seen as on a par with rationalist explanations of the foundations of predication and reasoning. Hume sought to replace the intellectual a-priori foundations of reasoning with psychological relations. Any dissenting rationalist philosopher will have to come up with a different notion of necessity and most importantly justify it by which I mean that the principle is actually applied or it is implicated within the subject’s psyche albeit unconsciously. To decide between Hume’s account of subjective necessity and an intellectualist account of objective necessity, the latter must show through an investigation of human faculties that the principle through which different ideas are united and inference from known to unknown instances of cause-effect relation in accordance with uniformity principle, that principle must actually be in use; it is the application of the principle that demands justification.

 

We saw in case of Locke’s critique of innate ideas, he objected that a child’s behaviour to avoid touching fire because it might burn comes from practical experience and not by deduction from some higher principles to which he clearly cannot claim access. Leibniz evaded such objections on the ground that they fail to discriminate between priority in terms of existence and in terms of familiarity. The innate knowledge of principles Leibniz does not understand in terms of innate propositional knowledge but in a dispositional sense and so he compares that knowledge to muscles and tendons, we can walk without specific knowledge about our muscles and tendons but walking itself is made possible by those physical features, due to their very existence not due to their knowledge. Further in NE 475 we saw Leibniz takes reason to be the cause of our judgements and the cause of the truth of those judgements. Hume’s objection can be understood as a further explication of Locke’s since he gives an alternative account of the origin of our ideas which is justified by the fact that a subject is making certain inferences is justified solely by experience which is grounded not in an intellectual principle but by an idea-enlivening imagination:

 

“Thus tho’ causation be a philosophical relation, as implying contiguity, succession, and constant conjunction, yet ’tis only so far as it is a natural relation, and produces an union among our ideas, that we are able to reason upon it, or draw any inference from it.” (65)

 

Hume’s is not a regularity account of causation since he sees constant conjunction grounded in natural relations of facility and vivacity and explains regularity just as a rationalist would through recourse to principles. Only Hume’s principles as he acknowledges do not allow justification to flow from known to unknown cases and instead of demonstrative necessity he substitutes subjective necessity. The necessary connexion in his case is simply a transition of thought that if made so often that it entrenches a habit or a custom. He can charge that a subject who reasons from cause to effect and effect to cause relies solely on his subjective feelings and no fact about the object allows him to infer one from the other. Hume and Leibniz may both agree that for the layman, the child and the animal inferences proceed from experience and no one has any knowledge of principles through which he makes inferences in everyday life:

 

“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 convinc’d 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.” (72-73)

 

Even if there is a ‘secret connexion’, that explains uniformity between cause and effect, such a secret cause can never be known and is not implicated in any inferences which determine our conduct in everyday life:

 

“……my intention never was to penetrate into the nature of bodies, or explain the secret causes of their operations. For besides that this belongs not to my present purpose, I am afraid, that such an enterprise is beyond the reach of human understanding, and that we can never pretend to know body otherwise than by those external properties, which discover themselves to the senses. As to those who attempt anything farther, I cannot approve of their ambition, till I see, in some one instance at least, that they have met with success. But at present I content myself with knowing perfectly the manner in which objects affect my senses, and their connexions with each other, as far as experience informs me of them. This suffices for the conduct of life; and this also suffices for my philosophy, which pretends only to explain the nature and causes of our perceptions, or impressions and ideas.” (46)

 

So the issue between a Leibniz and Hume comes down to this; Hume believes he has shown that inference of cause and effect depends on experience and experience depends on imagination while Leibniz believes that experience is not possible without Ideas or rational principles, more particularly of PNC and Principle of Harmony. But Leibniz has to justify why his explanation is better than Hume’s and the criteria Hume sets for that the principle must be found within human consciousness. So Hume’s arguments have a bite only if consciousness is regarded as prior to principles i.e. no principles must be accepted unless validated clearly and distinctly within subjective consciousness since meaning is always meaning for a subjective consciousness which then is the source of meaning of concepts and principles. If this condition is set then clearly Leibniz has no chance. But Leibniz’s entire philosophy hangs on rejecting the priority of consciousness over principles. 

Hume has set a problematic here which influenced Kant’s project to find whether a synthetic a-priori is possible or not. It became a very important question to find the principle that unites synthetic propositions. Even though Hume’s associative psychology was rejected by Kant himself since he figured the task of deduction of categories from experience to be doomed even then the question of what is the highest principle of thought or synthetic thought and whether synthetic a-priori propositions are possible or not remained important for him and philosophers that followed him and these questions were triggered by Hume’s critique of the causal principle that got through to Kant as he acknowledges in his Prolegomenon to any Future Metaphysic, Hume woke Kant from his dogmatic slumber.

 

Leibniz however reproved of this a-prioritization of consciousness which sought to limit the meaning of concepts to consciousness. As we have seen he criticized the clarity and distinctness criteria of truth in so far as it does not rigorously carry out the project of analysis, both the principles of non-contradiction and the principles of harmony to which every truth could be reduced demanded that the project of analysing go beyond what could clearly and distinctly be conceived by consciousness. He used this argument both against Descartes and against Locke and charges that both do not understand the difference between truths of facts and truths of principles and their restriction of meaning to consciousness was a result of confounding the two. I have used the same argument against Berkeley to show that he cannot draw ontological conclusions about the object of consciousness by referring to the subjective consciousness and argued that for the similar reasons Descartes real separation argument falters too. This really shows how alive Leibniz was to philosophical issues compared to many of his contemporaries and philosophers to come. In this section however my focus is on how Leibniz’s more metaphysical approach differs from an absolute phenomenology which seeks to restrict meaning to consciousness. But in order to bring this relation I will transgress the boundaries of time to bring Husserl into the discussion. Case in point is a very interesting discussion based on some of Husserl’s manuscript writings, in A.D. Smith’s Husserl and Cartesian Meditations (2003: 206-210).   

 

In the following passage Smith (2003: 185-186) explains the proof for absolute idealism that Husserl gives in an unpublished manuscript from 1908:

 

“Physical facts are ‘nothing over and above’ experiential facts – facts concerning the occurrence of actual and possible experiences in consciousness as a whole: an initially counter-intuitive, not to say shocking, claim. And so Husserl needs to show that our three conditions for supervenience are met in this area. The first condition – that certain experiential facts entail certain physical facts – is embodied in the analysis of reality that we have already investigated. Inclusion of an object in an ideal harmonization of experience entails the reality of that object:

 

“Let us assume . . . that the pertinent regularities of consciousness are actually maintained, that, in the course of consciousness taken universally, nothing whatever is lacking which is requisite for the appearance of a unitary world and for the rational theoretical cognition of such a world. All that being assumed, we now ask: is it still conceivable and not rather a countersense that the corresponding transcendent world does not exist? (Ideas I, 92)”

 

There can be no doubt about the rhetorical nature of this question. Husserl later added the following comment to a passage found just a few pages earlier in the same text: ‘The physical thing must exist if the continuity [of experience] goes on harmoniously ad infinitum’ (Ideas I, 86, note 229 [in Appendix 44 of the German edition]). Consider the appearance of this book to you now. If, to take the simplest scenario, no course of your future experience, and no course that your future experience would take, given all the possible ways that you might exercise bodily agency in the future, and no course that your past experience would have taken if your kinaestheses had been different, casts doubt on the veridicality of your current perception, and hence on the present reality of this book; and if these facts chime in with the experiences, actual and possible, of every other conscious being in the universe; then (necessarily) your experience is veridical, and this book really does exist. The actual existence of this physical object is entailed by such a harmonious experiential totality. In fact, we have seen that, where physical entities that are objects of experience are concerned, the entailment goes both ways. Given that this book is an object of perception for you, necessarily it exists only if your present perception of it ideally harmonizes with all the possible courses that your experience may take and might have taken, and with the really possible experiences of all other conscious subjects.”

 

The argument is closed with what Smith calls ideal verification:

 

“What cannot be known cannot exist; existence is knowability’ (Int III, 370).”

 

“The possibility that the world should in truth be nothing signifies an idea: the idea, namely, of a disharmony that proceeds to infinity.” (EP 392).

 

But in Idea 1.48 Husserl says that the possibility of any entity inaccessible to consciousness does not involve a formal contradiction but is ‘materially countersensical’. Probably he had in mind Kant’s thing in itself, the conception of which does not violate PNC but such an entity would be unthinkable or meaningless to us. But from this Husserl cannot derive the conclusion that ‘what cannot be known cannot exist, existence is knowability’. And this conclusion is what is needed for absolute idealism. Hence Husserl’s proof fails for the same reason that Berkeley’s did. But more important is the consideration here of harmony, without a harmony of ideal experiences no reality can be ascribed to an object or no meaning can be given to it and it is this harmony that proved a difficult problem for Husserl.

 

Husserl finally comes to a community of monads and compares his final metaphysical view with Leibniz’s with this difference that he arrived at it via his phenomenology. But a problem here arises for Husserl as Smith (2003: 206) explains:

 

“One important issue that Husserl never properly addresses, as far as I can tell, is why conscious experience actually takes the course that it does…..In particular, to focus on one specific aspect of this issue, Husserl never properly answers the question why there are just the actual hyletic data that there are and not others. ‘Past hylé prescribes no essential necessities in the monad for the occurrence of determinate, future hylé’, he writes. ‘Hylé comes accidentally’ (Int II, 14). However, for a world to exist of which monads have perceptual experience, there must be a harmony between the sensory experiences of these monads, and hence between their hyletic data – ‘a harmony between the collective factical subjects with respect to the irrational content of consciousness, . . . and hence a harmony of factical sensory data’ (Int II, 290–1). When we bear in mind, especially, that the harmony in question also governs the possible experiences of monads, the idea that which sensory data a monad experiences is simply a brute fact, or a matter of chance, is wholly unacceptable. We need to know what grounds the possibilities of experience that play such an important role in Husserl’s account of reality. Otherwise put: we need to know what makes a ‘real possibility’ more than a merely logical, or ‘empty’, possibility. On one occasion Husserl explicitly raises the problem:

 

“The flow of consciousness in a monad. At first a contingent one. It could have proceeded differently. Can we ask why it proceeded just as it did? What ground it has? All talk of ground and fathoming leads back to motivational connections in consciousness.” (B II 2, 25a)

 

Husserl’s solution to this problem is to say that a will to harmony is essential to a monad, he refers this will as his teleological explanation of the harmony of experience to which the monads are led to. But this solution does not work, as Smith (2003: 209) explains:

 

“But perhaps things are left open only if we focus on a single stream of consciousness. Perhaps when we bear in mind the totally interconnected universe of teleologically ordered monadic life, nothing will be left open, or left to chance. ‘If a nature exists, the stream of experiences cannot be arbitrary’ (B IV 6, 16b). Husserl also writes of nature as a ‘rule under which all monads . . . stand . . . Which changes in sensory constitution are possible is prescribed for all eternity’ (B II 2, 17a). This must be so, for we should recall that hyletic data correspond to ‘psychological’ sensations in a ‘soul’ in the constituted world; and these are causally determined by states of our bodies – which in turn are constituted by intersubjective consciousness in its totality. The non-arbitrariness of experience is entailed by the harmonious interconnection of monads. Still, it is one thing to show that monadic experience cannot be arbitrary; it is quite another to give a reason for precisely that course of experience that has actually unfolded. In other words, we have as yet been given no reason to think that the constraints on monadic experience that Husserl has mentioned are of such a nature as to narrow down all the abstractly possible courses of experience that consciousness might have followed down to just one – the actual one. In fact, he came increasingly to feel the inadequacy of the contrast between the necessary and the contingent at this level of ultimate reality:

 

“Do humans and animals exist ‘by chance’? The world is as it is. But it is contrary to sense to say ‘by chance’, for chance comprises a horizon of possibilities, and the chance thing itself signifies one of these possibilities – precisely the one that has actually entered upon the scene. ‘Absolute fact’: the word ‘fact’, in virtue of its meaning, is misapplied here . . . It is precisely the absolute – which cannot be called ‘necessary’ either – that is at the basis of all possibilities . . . , giving them sense and being. (Int III, 668–9)”.

 

It still remains the case, however, that any necessity that we can find in the flow of absolute consciousness is predicated upon such consciousness being teleologically ordered. And given that a teleological harmony among monads is not demanded by their very essence, such teleology must have a ground – though not one that is to be understood in terms of ‘causality’, which holds only within the constituted world (Ideas I, 111). That ground is God, who is ‘not the monadic totality itself, but its indwelling entelechy’ (Int III, 610). Teleology is ‘an ideal value that is realised’ (B II 2, 26a); and it is God who is the realizer.”

 

Hume also troubled by these exact questions. Early in the Treatise itself he says:

 

“As all simple ideas may be separated by the imagination, and may be united again in what form it pleases, nothing wou’d be more unaccountable than the operations of that faculty, were it not guided by some universal principles, which render it, in some measure, uniform with itself in all times and places. Were ideas entirely loose and unconnected, chance alone wou’d join them; and ’tis impossible the same simple ideas shou’d fall regularly into complex ones (as they commonly do) without some bond of union among them, some associating quality, by which one idea naturally introduces another. This uniting principle among ideas is not to be consider’d as an inseparable connexion; for that has been already excluded from the imagination: Nor yet are we to conclude, that without it the mind cannot join two ideas; for nothing is more free than that faculty….” (12)

 

It is here that Leibniz’s approach can be put in contrast with Husserl’s. The latter cannot explain the harmony of experience and any attempt to explain this harmony from experience is doomed to a vicious circularity. To bring this to perspective, Husserl’s problem was to explain the harmony of experiences through his phenomenology. But in order to do so Husserl had to ground the possibility of this harmony of experiences between the communities of monads. But what resources does Husserl have. He invoked the aid of certain motivational tendencies within a monad, but this leaves unexplained why a monad has those tendencies in the first place? Is it essential to a monad or inessential? Do all monads have the same tendencies? How does the harmony bind all monads in a uniform and constant manner? Husserl’s motivational tendencies like Hume’s does not deliver the concept of necessity and possibility that make uniformity possible. Also Smith mentions Husserl has not given us a reason as to why the course of experience was the one that unfolded. Finally Husserl has to appeal to God to ground these possibilities but yet he believes that this appeal can be made from within the confines of subjective life of a transcendental phenomenologist. So far from phenomenology restricting metaphysics, it itself is in need for metaphysics. This I believe would have been Leibniz’s suggestion to Husserl.

 

Now let us consider Hume’s quandary which he expressed in the Appendix of his Treatise:

 

“But having thus loosen’d all our particular perceptions, when I proceed to explain the principle of connexion, which binds them together, and makes us attribute to them a real simplicity and identity; I am sensible, that my account is very defective, and that nothing but the seeming evidence of the precedent reasonings cou’d have induc’d me to receive it. If perceptions are distinct existences, they form a whole only by being connected together. But no connexions among distinct existences are ever discoverable by human understanding. We only feel a connexion or a determination of the thought, to pass from one object to another. It follows, therefore, that the thought alone finds personal identity, when reflecting on the train of past perceptions that compose a mind, the ideas of them are felt to be connected together, and naturally introduce each other. However extraordinary this conclusion may seem, it need not surprize us. Most philosophers seem inclin’d to think, that personal identity arises from consciousness; and consciousness is nothing but a reflected thought or perception. The present philosophy, therefore, has so far a promising aspect. But all my hopes vanish, when I come to explain the principles that unite our successive perceptions in our thought or consciousness. I cannot discover any theory, which gives me satisfaction on this head. In short there are two principles, which I cannot render consistent; nor is it in my power to renounce either of them, viz. that all our distinct perceptions are distinct existences, and that the mind never perceives any real connexion among distinct existences. Did our perceptions either inhere in something simple and individual, or did the mind perceive some real connexion among them, there wou’d be no difficulty in the case. For my part, I must plead the privilege of a sceptic, and confess, that this difficulty is too hard for my understanding. I pretend not, however, to pronounce it absolutely insuperable. Others, perhaps, or myself, upon more mature reflection, may discover some hypothesis that will reconcile those contradictions.” (400)

 

Hume’s psychological explication of the concept of cause begins with showing that it is wrong to assume that the necessary connexion between cause and effect is a demonstrative necessity. So we need a different conception of necessity in order to arrive at the definition of cause. This necessity is a subjective necessity, mind’s determination to pass from one idea to the other. But this necessity does not explain regularity and uniformity of consciousness or the world of objects of consciousness. Hume confesses that with experience we can go only so far, a further step is needed to get to uniformity but that step cannot be taken. But this leads us to envisage that there might be a cause or a secret connexion that accounts for the regularity or uniformity of experience. Can Hume entertain this possibility? I think he does and he must. But what this implies is there is something within the concept of cause that allows us to entertain the possibility of causation beyond experience and this is what psychologism of Hume has to prevent from happening because the scope of application of the concept of cause is restricted to ideas and impressions. So we could perhaps say that the second conception of cause is a concept quite foreign to us since it implicates a kind of necessity of which we are unaware, but it is possible nevertheless. Hume has shown that the concept of cause that we use works with a notion of subjective necessity and it is this concept that has its possibilities restricted to the stream of consciousness. But he has not shown that a much stronger objective necessity does not exist in nature. A secret connexion might be possible but would not mean anything to us, which is not to say it is impossible. So Hume’s concept of cause and effect since they do not factor in for possibilities of a uniform and coherent experience cannot explain the rationality of the belief in the causal relation between two objects. Hume perhaps only realized this later when he made the observation that an ‘ought’ cannot be derived from an ‘is’. Hume’s necessity is the necessity of I cannot think otherwise, but from this he is not warranted to limit the scope of application of the concept of cause to possible experience since the possibility of experience exceeds the limits of what I can actually think. From, ‘this is how I think the concept of cause’, I cannot infer that this is how it has to be thought and only to consciousness could it be applied. Hence the copy principle if it rests on a natural relation cannot claim to be the entire story about the origin of a concept, it only says that ideas follow impressions, but it does not say that they must so follow. To make the point from Hume’s moral philosophy, it is one thing to say that reason is the slave of passions and quite another to say that reason ought to be the slave of passions which is what he says in the Treatise. So to say that the origin of a concept must be traced back to the impression is to say more than ideas follow impressions. If as Hume says that idea of existence adds nothing to the concept and to conceive is to conceive as existing, then there should be no possibility of a secret cause and the uniformity and regularity of experience must have been explained, but they are not explained by experience as Hume admits and this leaves open the possibility of unconceived existence and a secret connexion which goes against the psychologistic restrictions of the concept of cause to impressions and ideas for experience does not exhaust the possibilities of the use of the concept of cause and so Leibniz would reiterate these possibilities rest on the Idea repudiated by Hume. I further believe that the ‘is-ought’ problem is what led to Hume’s quandary he spelt out in the Appendix quoted above. He must have realized that qua subjective facts his principles do not account for the origin or the genesis of concepts because these principles demand uniformity and regularity to engender those results in the ideas they unite and hence presuppose the reality of a self which Hume had turned into a fiction born from union and connection of ideas. As a result he says his alternatives are either to ground perceptions in a simple and identical self or else allow his principles to notice a connexion between perceptions. The point is qua facts about subjective consciousness their own uniformity and regularity demands explanation and none is forthcoming in Hume’s philosophy. Principles have to account for why something was the way they are and not simply how something came about. From a meaningless flux of perceptions Hume’s principles cannot explain the genesis of meaning because those principles are as meaningless as the flux of perceptions. It seems highly improbably that an inconstant faculty like imagination must account for the constancy of union among ideas sufficient to yield an inter-subjective world. Hence Leibniz would charge Hume with confounding facts and principles. Hume can say this is how imaginations works but the description would not be explanation. On the one hand his psychologism demands that experience set a limit to possibility of experience and on the other he himself admits that this is not possible for experience, but if he did admit it he must show that possible experience exhausts all possibilities we find in the concept. On the one hand to conceive is to conceive as existing and so no unconceived existence must be possible while on the other hand it must be admitted that unconceived existence is possible. But there is no point in saying that unconceived existence would not mean anything to us, because the meaning of existence has not been exhausted by the concept of existence that we have formed and so within the net of our concept all possibilities of existence have not been exhausted. It is one thing to say that a concept means something to a subject and another to say that this is all that it can mean because if all possibilities have not been exhausted the meaning of a concept has not been reduced to what it means for a subject and hence there is a possibility to extend the use of our concept to meet those possibilities. 

 

Hume as we saw in the passage of the Appendix quoted above conveniently claimed the privilege of the sceptic to exonerate himself from the problems his own psychologistic project created for him. In this section Hume’s scepticism shall be examined. His argument in favour of scepticism comes in two stages. The first stage consists in showing that “knowledge degenerates into probability”. Hume’s reasoning goes through pointing out the possibility of error. Hume distinguishes between demonstrative sciences like mathematics which are “certain and infallible” (THN 121) and the application of these rules or principles. Experience informs us that “when we apply them our fallible and uncertain faculties are very apt to depart from them and fall into error.” To mitigate this contingency we try to inform our judgement with more checks and controls in which we “enlarge our view to comprehend a kind of history of all instances wherein our understanding has deceived us compared with those wherein its testimony was just and true.” If the past and the present circumstances of error are similar then probability will be low, if mistakes are rare then probability will be high and if there have been no mistakes in this respect then the probability will amount to proof. But even if it amounts to proof – it cannot be counted as knowledge because all knowledge is “certain and infallible” as in demonstrative sciences. In this case we depend on past experiences to correct present experiences and not on self-evident premises and there is no grey area between knowledge and probability:

“…..knowledge and probability are of such contrary and disagreeing natures, that they cannot well run insensibly into each other, and that because they will not divide, but must be either entirely present, or entirely absent. (THN 121).”

 

Hume makes it clear that the sceptical argument applies to the application of mathematics rather than the mathematical rules themselves. Every reasoning involves some transition of thought howsoever little and when that transition is made we are at the level of probability rather than demonstration and hence even simple reasoning like 2+2=4 is also probable rather than infallible – the certainty that it has is the certainty of a proof rather than of intuition or demonstration even if the difference is mighty little that does not change the fact that there is a difference. This is the reason even mathematicians constantly check on the derivation of their theorems and calculations to avoid error and even take technical assistance for it especially when the proof is a long one. But the reduction of long-winded proofs to simple axioms, if they involve some transition of thought or reasoning they would have the status of probability rather than demonstration. Mathematical definitions are got through the ideas themselves while mathematical reasoning involves the comparison of different Ideas. That makes a world of difference between the two.

 

The second stage of the argument is to ensure the reliability of a first judgement in empirical reasoning we would have to turn to a second more stricter judgement and the process would lead us to an infinite regress:

 

“Having thus found in every probability, beside the original uncertainty inherent in the subject, a new uncertainty deriv’d from the weakness of that faculty, which judges, and having adjusted these two together, we are oblig’d by our reason to add a new doubt deriv’d from the possibility of error in the estimation we make of the truth and fidelity of our faculties. (THN 122)”

 

And each new judgement would only weaken our confidence in the prior judgement. So the confidence we repose in the third judgement:

 

“must itself be weaken’d by a fourth doubt of the same kind, and so on in infinitum; till at last there remain nothing of the original probability, however great we may suppose it to have been, and however small the diminution by every new uncertainty. No finite object can subsist under a decrease repeated in infinitum; and even the vastest quantity, which can enter into human imagination, must in this manner be reduc’d to nothing. . . . When I reflect on the natural fallibility of my judgment, I have less confidence in my opinions, than when I only consider the objects concerning which I reason; and when I proceed still farther, to turn the scrutiny against every successive estimation I make of my faculties, all the rules of logic require a continual diminution, and at last a total extinction of belief and evidence. (122)”

 

This argument is not blocked on the grounds that we can distinguish between the levels where a judger trusts his experience of an object from the level where he founds a second judgement about the first judgement. If there is no reason to doubt our judgement at the first level we need not proceed to a second level and thought and action would remain unaffected because they depend on the first level of judgement. What is important to understand is that Hume’s argument is not about probable reasoning but about the rationality of probable reasoning or its rational basis and which rationality is constituted by correction through checks and controls or regulating the present experience by the past coupled with the belief in the uniformity principle. As Waxman (2005) puts it nicely:

 

“Since experience is “the true standard” (THN 78) of all rational probable reasoning, any inference we draw from an impression to an idea that disregards, or deliberately flouts, all the checks and controls on which we rely in order to bring our reasoning into conformity with this standard must be regarded, respectively, as unreasonable or irrational. Checks and controls are indispensable to preventing the understanding from becoming the plaything of every whim, ebb and flow of the passions, trivial considerations of interest or pleasure, laziness, hastiness, miseducation, and every other kind of “unphilosophical” influence that experience shows to increase the likelihood of error (Treatise I/iii/§13 and Enquiry X/ii). Even if the judgment is true, it would be as arbitrary and devoid of cognitive worth as the calculations of someone who always persisted in his first result and refused all checks and controls. Accordingly, a second judgment about the reliability of our faculties, based on the application of the requisite checks and controls, is an essential part of all rational probable reasoning as such, not merely a discretionary adjunct. But what about this new judgment? If it were arrived at without the guidance of the checks and controls requisite to ensure its conformity to the true standard of empirical rationality, then the whole reasoning, composed of this judgment together with the original one, will fail to be rational. So in order to persist in a course of probable reasoning that is at no point unreasonable or irrational, a third judgment is necessary to apply checks and controls to the second, then a fourth to apply checks and controls to their third, and so on ad infinitum.”

 

The purpose of Hume’s argument is to show that the supreme principle of human understanding is facility vivacity feeling which constitute the relations between Ideas and thereby he can show that the source of human understanding is something irrational rather than something rational like thought. He gives the sceptical argument not to prove scepticism but to refute both scepticism and dogmatism at the same time:

“Reason first appears in possession of the throne, prescribing laws, and imposing maxims, with an absolute sway and authority. Her enemy, therefore, is oblig’d to take shelter under her protection, and by making use of rational arguments to prove the fallaciousness and imbecility of reason, produces, in a manner, a patent under her hand and seal. This patent has at first an authority, proportion’d to the present and immediate authority of reason, from which it is deriv’d. But as it is suppos’d to be contradictory to reason, it gradually diminishes the force of that governing power, and its own at the same time; till at last they both vanish away into nothing, by a regular and just diminution. The sceptical and dogmatical reasons are of the same kind, tho’ contrary in their operation and tendency; so that where the latter is strong, it has an enemy of equal force in the former to encounter; and as their forces were at first equal, they still continue so, as long as either of them subsists; nor does one of them lose any force in the contest, without taking as much from its antagonist. (125)”

 

Hume argues that belief like an itch, hunger etc. is not subject to the principle of non-contradiction and in a reductio ad absurdum he points out the consequences of taking belief to be thought. Consider the premises and conclusion of the argument for scepticism in a schematic form:

P1…..PN

Therefore C (Sceptical Conclusion)

Now the Rationalist should be able to block the conclusion C but on what grounds can he do that? He cannot dispute the premises because he agrees that knowledge and probability have no grey area in common and if there is even a slight possibility of error it does not constitute knowledge but probability. So from these premise the conclusion follows. If beliefs always follow where reason leads it to then the sceptical conclusion would be unavoidable because one cannot believe the premises to be true and conclusion to be false. But if beliefs follow instincts that nature has fashioned within us then nature can prevent us from accepting the sceptical conclusion. It can block the transition from premises to conclusion by preventing the transference of vivacity or facility feeling or opposing the conclusion through greater contrary feeling of facility or vivacity. Hence it is nature that “breaks the force of all sceptical arguments in time, and keeps them from having any considerable influence on the understanding” (125). Experience and habit derive their power to influence human thought and action entirely from this facility and vivacity feeling. The realm of the cognitive thereby is reduced to the realm of feelings and taste – we believe what due to our human nature we are condemned to believe irrespective of whether or not it meets the standards of reason. It is also due to human nature that we can form some order in the cognitive arena by regulating present beliefs in accordance with the past through some checks and controls – but that does not alter the nature of rationality which is structured not in accordance with Reason as the rationalist understands it but human nature or the psychological mechanisms it has built into us. The conclusion that follows is anything that involves some transition of thought and thus any form of reasoning and thus the entire structure of human understanding has vivacity and facility feeling as its supreme principle which now can be seen as displacing reason and thought. So the challenge to the rationalist is to show how we derive an objective validity from a subjective one. Hume as we have seen cannot solve this problem because no ‘ought’ comes from an ‘is’. However Hume can claim the privilege of the sceptic to evade this demand and yet avoid scepticism by appealing to his psychology of belief which an unfathomable nature has condemned him to. To elaborate let’s consider Popkin’s (1951) explanation of why Hume is a consistent sceptic:

 

“Hume's full view of himself as the ' consistent' Pyrrhonist comes out in the picture that he painted of what the true sceptic is like, both in the character of Philo in the Dialogues, and in various remarks in all his philosophical writings. The true Pyrrhonist is both a dogmatist and a sceptic. In being entirely the product of nature he welds his schizophrenic personality and philosophy together. He believes whatever nature leads him to believe, no more and no less. He is compelled to believe, and in accepting the compulsion he is exhibiting his scepticism. He is led to philosophize by certain natural inclinations, and through them to come to certain conclusions, and in so doing he is again exhibiting his scepticism. 'I may, nay I must yield to the current of nature, in submitting to my senses and understanding; and in this blind submission I shew most perfectly my sceptical disposition and principles'. Even the more 'mitigated scepticism' which Hume proposed, as an alternative to extreme scepticism, at the end of the Enquiry, comes to no more than this. This sceptic, once thoroughly convinced of the force of the Pyrrhonian doubts, and seeing that it is only the strong power of natural instinct that allows him to go on, will philosophize because he gains pleasure from it, and because he has a propensity to reason.”

 

Against dogmatism Hume plays a sceptic and against the sceptic he plays the role of a dogmatist, this is very clear in the entire Dialogues Concerning Natural Religion, from which I take note of the following passage:

 

“It seems evident, that the dispute between the sceptics and dogmatists is entirely verbal, or at least regards only the degrees of doubt and assurance, which we ought to indulge with regard to all reasoning: And such disputes are commonly at the bottom, verbal, and admit not of any precise determination. No philosophical dogmatist denies, that there are difficulties both with regard to the senses and to all science: and that these difficulties are in a regular, logical method, absolutely insolveable. No sceptic denies, that we lie under an absolute necessity, notwithstanding these difficulties, of thinking, and believing, and reasoning with regard to all kind of subjects, and even of frequently assenting with confidence and security. The only difference, then, between these sects, if they merit that name, is, that the sceptic, from habit, caprice, or inclination, insists most on the difficulties; the dogmatist, for like reasons, on the necessity.”

 

Quite amusingly, commenting on this passage Popkin (1951) calls a perfect pyrrhonist a split personality:

 

“He alone believed that both the difficulties and the necessity exist. The picture of the two, the dogmatist and sceptic, is a picture of the perfect Pyrrhonist in his two moods, his split personality. In one mood, the difficulties overcome him, in another, the necessities do. Only by being both can one be a philosopher, and live according to nature.”

 

Hume’s point is that nature has put within us two contradictory tendencies or Eros to use Plato’s words, to satisfy one compulsion we need to philosophize but this Eros is insatiable which forces us to become a sceptic but nature does not let us remain a sceptic, it brings us back to everyday life where we act; scepticism as it were cancels itself while taking the dogmatic with him. This is also how Hume evades the problems in his psychologism, on the one hand ‘ought’ cannot be derived from ‘is’, on the other we do draw that conclusion. There is no explanation why or how we manage to derive ‘ought’ from ‘is’, all we can say is that nature takes this course.

 

But Popkin points out that this overcoming of Pyrrhonism would fail if:

 

“There is, of course, a point at which even Hume's formulation of 'consistent' Pyrrhonism breaks down. Hume requires a theoretical framework in order to distinguish between epistemological Pyrrhonism and one's psychological abilities. Such a frame-work will constitute a systematic position not open to Pyrrhonian attacks if the distinction between epistemology and psychology which is made within it is any more than a strong natural belief of David Hume.”

 

Hume’s natural belief allows the sceptic to switch from scepticism to everyday life dogmatist mode. So this separation between epistemology and psychology allows Hume to give a psychological refutation of scepticism by overcoming epistemological concerns of the sceptic. But this psychological account depends on natural belief which is nothing more than vivacity feeling which is produced when there is an immediate object of consciousness and which feeling is taken up by imagination to enliven ideas even when no immediate object is present to consciousness. So this account depends on dogmatism of immediacy of consciousness which separates reality from fiction and hence the Pyrrhonian would not accept this psychological account of natural belief. The prerogative to reality lies within an immediacy felt in consciousness but while immediacy is a psychological matter, prerogative to reality is an epistemological one. So again we have a conflation of epistemological and psychological issues because immediacy of consciousness is taken as evidence for reality and vivacity feeling is what it is because it produces the feeling that something is real. The distinction between appearance and reality is an epistemological distinction but drawn from a psychological description. Hence contra Popkin we cannot take Hume to be a perfect Pyrrhonist and that he is so since he found a way to overcome scepticism; on the contrary scepticism seems to overcome Hume.