Read like Albert Einstein

By Terry, Kate

Albert Einstein favorite books. Good books to read recommended by the scientist.
Albert Einstein collection: "A treatise of human nature", "Anna Karenina", "Critique of pure reason", "Don Quixote", "The brothers Karamazov", "The world as will and representation".
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• Language: English
• Publisher: Aegitas
• Release date: Feb 9, 2016
• ISBN: 9781772468816

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Read like Albert Einstein

Kate Terry

David Hume

A Treatise of Human Nature

Background

While many scholars today consider the Treatise to be Hume's most important work and one of the most important books in the history of philosophy, the public in Britain did not at first agree. Hume himself described the (lack of) public reaction to the publication of the Treatise by writing that the book fell dead-born from the press.

Hume intended to see whether the Treatise met with success and, if so, to complete it with books devoted to morals, politics, and criticism. It did not meet with success, and so was not completed.

After deciding that the Treatise had problems of style rather than of content, he reworked some of the material for more popular consumption in An Enquiry Concerning Human Understanding (1748). It did not prove extremely successful either, but was somewhat more so than the Treatise. He later also cast anew Book 3 of the Treatise as An Enquiry Concerning the Principles of Morals (1751), which Hume wrote is of all my writings, historical, philosophical, or literary, incomparably the best.

The Treatise is now in the public domain. Books 1 and 2 were originally published in 1738 (or 1739), while Book 3 was published in 1740.

Introduction

Hume's introduction presents the idea of placing all science and philosophy on a novel foundation: namely, an empirical investigation into human psychology. He begins by acknowledging that common prejudice against metaphysical reasonings [i.e., any complicated and difficult argumentation], a prejudice formed in reaction to the present imperfect condition of the sciences (including the endless scholarly disputes and the inordinate influence of eloquence over reason). But since the truth must lie very deep and abstruse where the greatest geniuses have not found it, careful reasoning is still needed. All sciences, Hume continues, ultimately depend on the science of man: knowledge of the extent and force of human understanding,... the nature of the ideas we employ, and... the operations we perform in our reasonings is needed to make real intellectual progress. So Hume hopes to explain the principles of human nature, thereby propos[ing] a compleat system of the sciences, built on a foundation almost entirely new, and the only one upon which they can stand with any security. But an a priori psychology would be hopeless: the science of man must be pursued by the experimental methods of the natural sciences. This means we must rest content with well-confirmed empirical generalizations, forever ignorant of the ultimate original qualities of human nature. And in the absence of controlled experiments, we are left to glean up our experiments in this science from a cautious observation of human life, and take them as they appear in the common course of the world, by men's behaviour in company, in affairs, and in their pleasures.

Book 1: Of the Understanding

Part 1: Of ideas, their origin, composition, connexion, abstraction, etc.

Hume begins by arguing that each simple idea is derived from a simple impression, so that all our ideas are ultimately derived from experience: thus Hume accepts concept empiricism and rejects the purely intellectual and innate ideas found in rationalist philosophy. Hume's doctrine draws on two important distinctions: between impressions (the forceful perceptions found in experience, all our sensations, passions and emotions) and ideas (the faint perceptions found in thinking and reasoning), and between complex perceptions (which can be distinguished into simpler parts) and simple perceptions (which cannot). Our complex ideas, he acknowledges, may not directly correspond to anything in experience (e.g., we can form the complex idea of a heavenly city). But each simple idea (e.g., of the color red) directly corresponds to a simple impression resembling it—and this regular correspondence suggests that the two are causally connected. Since the simple impressions come before the simple ideas, and since those without functioning senses (e.g., blindness) end up lacking the corresponding ideas, Hume concludes that simple ideas must be derived from simple impressions. Notoriously, Hume considers and dismisses the 'missing shade of blue' counterexample.

Briefly examining impressions, Hume then distinguishes between impressions of sensation (found in sense experience) and impressions of reflection (found mainly in emotional experience), only to set aside any further discussion for Book 2's treatment of the passions. Returning to ideas, Hume finds two key differences between ideas of the memory and ideas of the imagination: the former are more forceful than the latter, and whereas the memory preserves the order and position of the original impressions, the imagination is free to separate and rearrange all simple ideas into new complex ideas. But despite this freedom, the imagination still tends to follow general psychological principles as it moves from one idea to another: this is the association of ideas. Here Hume finds three natural relations guiding the imagination: resemblance, contiguity, and causation. But the imagination remains free to compare ideas along any of seven philosophical relations: resemblance, identity, space/time, quantity/number, quality/degree, contrariety, and causation. Hume finishes this discussion of complex ideas with a skeptical account of our ideas of substances and modes: though both are nothing more than collections of simple ideas associated together by the imagination, the idea of a substance also involves attributing either a fabricated "unknown something, in which [the particular qualities] are supposed to inhere" or else some relations of contiguity or causation binding the qualities together and fitting them to receive new qualities should any be discovered.

Hume finishes Part 1 by arguing (following Berkeley) that so-called 'abstract ideas' are in fact only particular ideas used in a general way. First, he makes a three-point case against indeterminate ideas of quantity or quality, insisting on the impossibility of differentiating or distinguishing a line's length from the line itself, the ultimate derivation of all ideas from fully determinate impressions, and the impossibility of indeterminate objects in reality and hence in idea as well. Second, he gives a positive account of how abstract thought actually works: once we are accustomed to use the same term for a number of resembling items, hearing this general term will call up some particular idea and activate the associated custom, which disposes the imagination to call up any resembling particular ideas as needed. Thus the general term 'triangle' both calls up an idea of some particular triangle and activates the custom disposing the imagination to call up any other ideas of particular triangles. Finally, Hume uses this account to explain so-called distinctions of reason (e.g., distinguishing the motion of a body from the body itself). Though such distinctions are strictly impossible, Hume argues, we achieve the same effect by noting the various points of resemblance between different objects.

Part 2: Of the ideas of space and time

Hume's system concerning space and time features two main doctrines: the finitist doctrine that space and time are not infinitely divisible, and the relationist doctrine that space and time cannot be conceived apart from objects. Hume begins by arguing that, since the capacity of the mind is limited, our imagination and senses must eventually reach a minimum: ideas and impressions so minute as to be indivisible. And since nothing can be more minute, our indivisible ideas are adequate representations of the most minute parts of [spatial] extension. Upon consideration of these clear ideas, Hume presents a few arguments to demonstrate that space and time are not infinitely divisible, but are instead composed of indivisible points. On his account, the idea of space is abstracted from our sense experience (arrangements of colored or tangible points), and the idea of time from the changing succession of our own perceptions. And this means that space and time cannot be conceived on their own, apart from objects arranged in space or changing across time. Thus we have no idea of absolute space and time, so that vacuums and time without change are ruled out.

Hume then defends his two doctrines against objections. In defending his finitism against mathematical objections, he argues that the definitions of geometry actually support his account. He then argues that since important geometric ideas (equality, straightness, flatness) do not have any precise and workable standard beyond common observation, corrective measurements, and the imaginary standards we are naturally prone to fabricate, it follows that the extremely subtle geometric demonstrations of infinite divisibility cannot be trusted. Next, Hume defends his relationist doctrine, critically examining the alleged idea of a vacuum. No such idea can be derived from our experience of darkness or motion (alone or accompanied by visible or tangible objects), but it is indeed this experience that explains why we mistakenly think we have the idea: according to Hume, we confuse the idea of two distant objects separated by other visible or tangible objects with the very similar idea of two objects separated by an invisible and intangible distance. With this diagnosis in hand, he replies to three objections from the vacuist camp—adding on a skeptical note that his intention never was to penetrate into the nature of bodies, or explain the secret causes of their operations, but only to explain the nature and causes of our perceptions, or impressions and ideas.

In the final section, Hume accounts for our ideas of existence and of external existence. First, he argues that there is no distinct impression from which to derive the idea of existence. Instead, this idea is nothing more than the idea of any object, so that thinking of something and thinking of it as existent are the very same thing. Next, he argues that we cannot conceive of anything beyond our own perceptions; thus our conception of the existence of external objects is at most a relative idea.

Part 3: Of knowledge and probability

Sections 1–3

Hume recalls the seven philosophical relations, and divides them into two classes: four which can give us knowledge and certainty, and three which cannot. (This division reappears in Hume's first Enquiry as relations of ideas and matters of fact, respectively.) As for the four relations, he notes, all can yield knowledge by way of intuition: immediate recognition of a relation (e.g., one idea as brighter in color than another). But with one of the four, proportions in quantity or number, we commonly achieve knowledge by way of demonstration: step-by-step inferential reasoning (e.g., proofs in geometry). Hume makes two remarks on demonstrative reasoning in mathematics: that geometry is not as precise as algebra (though still generally reliable), and that mathematical ideas are not spiritual and refin'd perceptions, but instead copied from impressions.

As for the other three relations, two of them (identity and space/time) are simply a matter of immediate sensory perception (e.g., one object next to another). But with the last relation, causation, we can go beyond the senses, by way of a form of inferential reasoning he calls probable reasoning. Here Hume embarks on his celebrated examination of causation, beginning with the question From what impression do we derive our idea of causation? All that can be observed in a single instance of cause and effect are two relations: contiguity in space, and priority in time. But Hume insists that our idea of causation also includes a mysterious necessary connection linking cause to effect. [S]topt short by this problem, Hume puts the idea of necessary connection on hold and examines two related questions: Why do we accept the maxim 'whatever begins to exist must have a cause'?, and How does the psychological process of probable reasoning work? Addressing the first question, Hume argues that the maxim is not founded on intuition or demonstration (contending that we can at least conceive of objects beginning to exist without a cause), and then rebuts four alleged demonstrations of the maxim. He concludes that our acceptance of this maxim must be somehow drawn from observation and experience, and thus turns to the second question.

Sections 4–8

Hume develops a detailed three-stage psychological account of how probable reasoning works (i.e., how the judgment operates). First, our senses or memory must present us with some object: our confidence in this perception (our assent) is simply a matter of its force and vivacity. Second, we must make an inference, moving from our perception of this object to an idea of another object: since the two objects are perfectly distinct from each other, this inference must draw on past experience of the two objects being observed together again and again. (This constant conjunction is promptly filed alongside contiguity and priority, in Hume's still-developing account of our idea of causation.) But what exactly is the process by which we draw on past experience and make an inference from the present object to the other object?

Here the famous problem of induction arises. Hume argues that this all-important inference cannot be accounted for by any process of reasoning: neither demonstrative reasoning nor probable reasoning. Not demonstrative reasoning: it cannot be demonstrated that the future will resemble the past, for [w]e can at least conceive a change in the course of nature, in which the future significantly differs from the past. And not probable reasoning: that kind of reasoning itself draws on past experience, which means it presupposes that the future will resemble the past. In other words, in explaining how we draw on past experience to make causal inferences, we cannot appeal to a kind of reasoning that itself draws on past experience—that would be a vicious circle that gets us nowhere.

The inference is not based on reasoning, Hume concludes, but on the association of ideas: our innate psychological tendency to move along the three natural relations. Recall that one of the three is causation: thus when two objects are constantly conjoined in our experience, observing the one naturally leads us to form an idea of the other. This brings us to the third and final stage of Hume's account, our belief in the other object as we conclude the process of probable reasoning (e.g., seeing wolf tracks and concluding confidently that they were caused by wolves). On his account of belief, the only difference between a believed idea and a merely conceived idea lies in the belief's additional force and vivacity. And there is a general psychological tendency for any lively perception to transfer some of its force and vivacity to any other perception naturally related to it (e.g., seeing the picture of an absent friend makes our idea of the friend more lively, by the natural relation of resemblance). Thus in probable reasoning, on Hume's account, our lively perception of the one object not only leads us to form a mere idea of the other object, but enlivens that idea into a full-fledged belief. (This is only the simplest case: Hume also intends his account to explain probable reasoning without conscious reflection as well as probable reasoning based on only one observation.)

Sections 9–13

Hume now pauses for a more general examination of the psychology of belief. The other two natural relations (resemblance and contiguity) are too feeble and uncertain to bring about belief on their own, but they can still have a significant influence: their presence strengthens our preexisting convictions, they bias us in favor of causes that resemble their effects, and their absence explains why so many don't really believe in an afterlife. Similarly, other kinds of custom-based conditioning (e.g., rote learning, repeated lying) can induce strong beliefs. Next, Hume considers the mutual influence of belief and the passions, and of belief and the imagination. Only beliefs can have motivational influence: it is the additional force and vivacity of a belief (as opposed to a mere idea) that makes it able to operate on the will and passions. And in turn we tend to favor beliefs that flatter our passions. Likewise, a story must be somewhat realistic or familiar to please the imagination, and an overactive imagination can result in delusional belief. Hume sees these diverse phenomena as confirming his 'force and vivacity' account of belief. Indeed, we keep ourselves from augmenting our belief upon every encrease of the force and vivacity of our ideas only by soberly reflecting on past experience and forming general rules for ourselves.

Hume then examines probable reasoning under conditions of empirical uncertainty, distinguishing proofs (conclusive empirical evidence) from mere probabilities (less than conclusive empirical evidence). Beginning with a brief section on the probability of chances, he gives the example of a six-sided die, four sides marked one way and two sides marked another way: background causes lead us to expect the die to land with a side facing up, but the force of this expectation is divided indifferently across the six sides, and finally reunited according to the die's markings, so that we end up expecting the one marking more than the other. This is mainly prelude to the probability of causes, where Hume distinguishes three species of probability: (1) imperfect experience, where young children haven't observed enough to form any expectations, (2) contrary causes, where the same event has been observed to have different causes and effects in different circumstances, due to hidden factors, and (3) analogy, where we rely on a history of observations that only imperfectly resemble the present case. He focuses on the second species of probability (specifically reflective reasoning about a mixed body of observations), offering a psychological explanation much like that of the probability of chances: we begin with the custom-based impulse to expect that the future will resemble the past, divide it across the particular past observations, and then (reflecting on these observations) reunite the impulses of any matching observations, so that the final balance of belief favors the most frequently observed type of case.

Hume's discussion of probability finishes with a section on common cognitive biases, starting with recency effects. First, the more recent the event whose cause or effect we are looking for, the stronger our belief in the conclusion. Second, the more recent the observations we draw on, the stronger our belief in the conclusion. Third, the longer and more discontinuous a line of reasoning, the weaker our belief in the conclusion. Fourth, irrational prejudices can be formed by overgeneralizing from experience: the imagination is unduly influenced by any superfluous circumstances that have frequently been observed to accompany the circumstances that actually matter. And paradoxically, the only way to correct for the pernicious influence of general rules is to follow other general rules, formed by reflecting on the circumstances of the case and our cognitive limitations. Throughout the section, Hume uses his 'force and vivacity' account of belief to account for these unphilosophical influences on our reasoning.

Sections 14–16

Having completed his account of probable reasoning, Hume returns to the mysterious idea of necessary connection. He rejects some proposed sources of this idea: not from the known qualities of matter, nor from God, nor from some unknown quality of matter, nor from our power to move our body at will. For all ideas derive from experience, and in no single case do we observe anything like a necessary connection linking cause to effect. But the idea does arise upon repeated observations, and since mere repetition cannot produce anything new in the objects themselves, the idea must therefore derive from something new in our mind. Thus he concludes that the idea of necessary connection is derived from inside: from the feeling we experience when the mind (conditioned by repeated observation) makes a causal inference. And though his conclusion is shocking to common sense, Hume explains it away by noting that the mind has a great propensity to spread itself on external objects. Finally, he offers two definitions of 'cause': one in terms of the objects (viz. their relations of priority, contiguity, and constant conjunction), and another in terms of the mind (viz. the causal inference it makes upon observing the objects).

Hume finishes Part 3 with two brief sections. First, he presents eight rules for empirically identifying true causes: after all, if we leave aside experience, any thing may produce any thing. Second, he compares human reason with animal reason, a comparison which clinches the case for his associationist account of probable reasoning: after all, animals are clearly capable of learning from experience through conditioning, and yet they are clearly incapable of any sophisticated reasoning.

Part 4: Of the sceptical and other systems of philosophy

Sections 1–2

Hume begins Part 4 by arguing that all knowledge degenerates into probability, due to the possibility of error: even the rock solid certainty of mathematics becomes less than certain when we remember that we might have made a mistake somewhere. But things get worse: reflection on the fallibility of our mind, and meta-reflection on the fallibility of this first reflection, and so on ad infinitum, ultimately reduces probability into total skepticism—or at least it would, if our beliefs were governed by the understanding alone. But according to Hume, this extinction of belief does not actually happen: having beliefs is part of human nature, which only confirms Hume's account of belief as more properly an act of the sensitive, than of the cogitative part of our natures. And as for why we do not sink into total skepticism, Hume argues that the mind has a limited quantity of force and activity, and that difficult and abstruse reasoning strains the imagination, hindering the regular flowing of the passions and sentiments. As a result, extremely subtle skeptical argumentation is unable to overpower and destroy our beliefs.

Next comes an extremely lengthy account of why we believe in an external physical world: i.e., why we think objects have a continued (existing when unobserved) and distinct (existing external to and independent of the mind) existence. Hume considers three potential sources of this belief—the senses, reason, and the imagination. It's not the senses: clearly they are incapable of informing us of anything existing unobserved. Nor can they inform us of objects with distinct existence: the senses present us with sense perceptions only, which means they cannot present them as representations of some further objects, nor present them as themselves objects with distinct existence (for the senses are unable to identify the mysterious self, distinguishing it from and comparing it with sense perceptions). And it's not reason: even children and fools believe in an external world, and nearly all of us naïvely take our perceptions to be objects with a continued and distinct existence, which goes against reason. So this belief must come from the imagination.

But only some of our impressions bring about the belief: namely, impressions with constancy (invariableness in appearance over time) and coherence (regularity in changing appearances). Thus Hume proceeds to develop an account of how the imagination, fed with coherent and constant impressions, brings about belief in objects with continued (and therefore distinct) existence. Given coherent impressions, we have only one way of accounting for our observations consistently with past experience: we form the supposition that certain objects exist unperceived. And since this supposes more regularity than is found in past observation, causal reasoning alone cannot explain it: thus Hume invokes the imagination's tendency to continue in any train of thinking inertially, like a galley put in motion by the oars. But to explain so vast an edifice, as... the continu'd existence of all external bodies, Hume finds it necessary to bring constancy into his account, as follows: (1) Identity is characterized as invariableness and uninterruptedness over time. (2) Since the mind tends to confuse closely resembling ideas, it will naturally confuse a case of interrupted observation of an invariable object with a case of perfect identity. (3) This combination of perfect identity and interrupted observation creates cognitive dissonance, which is resolved by fabricating continued existence. (4) This fiction is enlivened into a full-fledged belief by the memory's lively impressions of the observed object.

But this naïve belief in the continued and distinct existence of our perceptions is false, as is easily shown by simple observations. Philosophers therefore distinguish mental perceptions from external objects. But, Hume argues, this philosophical system of a double existence could never arise directly from reason or the imagination. Instead, it is the monstrous offspring of two principles, viz. our naïve belief in the continued and distinct existence of our perceptions, along with our more reflective conclusion that perceptions must depend upon the mind. It is only by passing through the naïve natural belief that the imagination fabricates this arbitrarily invented philosophical system. Hume ends by voicing strong doubts about any system based on such trivial qualities of the fancy, and recommending carelessness and in-attention as the only remedy for skepticism.

Sections 3–6

Next, Hume presents a brief critique of antient philosophy (traditional Aristotelianism) and modern philosophy (post-Scientific Revolution mechanical philosophy), focusing on their rival conceptions of external objects. As for the incomprehensible fictions of the antient philosophy, he thinks they can shed further light on human psychology. We begin with contradictions in our ideas of bodies: between seeing bodies as ever-changing bundles of distinct qualities, and seeing bodies as simple unities that retain their identity across time. We reconcile these contradictions by fabricating something unknown and invisible that underlies change and unifies the distinct qualities together: i.e., the substance of traditional metaphysics. Similar fictions, fabricated by the imagination to resolve similar difficulties, include substantial forms, accidents, and occult qualities, all meaningless jargon used only to hide our ignorance. Modern philosophy, however, claims to disown the trivial propensities of the imagination and follow only solid reason (or, for Hume, the solid, permanent, and consistent principles of the imagination). Its fundamental principle is that secondary qualities (colours, sounds, tastes, smells, heat and cold) are nothing but impressions in the mind, as opposed to the primary qualities (motion, extension, and solidity) that exist in reality. But Hume argues that primary qualities cannot be conceived apart from the secondary qualities. Thus if we follow solid reason and exclude the latter, we will be forced to contradict our own senses by excluding the former as well, thereby denying the entire external world.

Hume then examines the nature of the mind, starting with the materialist-dualist debate over the substance of the mind. He rejects the whole question as unintelligible, for we have no impression (and therefore no idea) of any substance, and defining 'substance' as something which may exist by itself doesn't help (each of our perceptions, Hume argues, would then count as a distinct substance). Turning to the question of the "local conjunction of mind and matter, he considers and endorses the anti-materialist argument which asks how unextended thoughts and feelings could possibly be conjoined at some location to an extended substance like a body. Hume then provides a psychological account of how we get taken in by such illusions (in his example, a fig and an olive are at opposite ends of a table, and we mistakenly suppose the sweet figgy taste to be in one location and the bitter olive taste to be in the other), arguing that unextended perceptions must somehow exist without having a location. But the contrary problem arises for dualists: how can extended perceptions (of extended objects) possibly be conjoined to an simple substance? Indeed, Hume waggishly adds, this is basically the same problem that theologians commonly press against Spinoza's naturalistic metaphysics: thus if the theologians manage to solve the problem of extended perceptions belonging to a simple substance, then they give that famous atheist" Spinoza a solution to the problem of extended objects as modes of a simple substance. Finally, Hume examines causal relations, arguing on behalf of materialists that our observations of regular mind-body correlations are enough to show the causal dependence of the mind on the body, and that, since we are never sensible of any connexion betwixt causes and effects in general, our inability to detect any a priori connection between mind and body does nothing to show causal independence.

Finally, Hume weighs in on the topic of personal identity. Notoriously, he claims that introspective experience reveals nothing like a self (i.e., a mental substance with identity and simplicity), but only an ever-changing bundle of particular perceptions. And so he gives a psychological account of why we believe in personal identity, arguing that the identity, which we ascribe to the mind of man, is only a fictitious one, and of a like kind with that which we ascribe to vegetables and animal bodies. Hume's account starts with our tendency to confound resembling but contrary ideas, viz. the idea of a perfect identity and the idea of a succession of related objects, an absurdity we justify by means of a fiction, either of something invariable and uninterrupted, or of something mysterious and inexplicable, or at least... a propensity to such fictions. Next, he argues that the everyday objects we ascribe identity to (e.g., trees, humans, churches, rivers) are indeed such as consist of a succession of related objects, connected together by resemblance, contiguity, or causation: thus we overlook relatively minor changes, especially when slow and gradual, and especially when connected by "some common end or purpose or a sympathy of parts to their common end. Applying all this to personal identity, he argues that since all our perceptions are distinct from each other, and since we never observe any real connexion among objects", our perceptions are merely associated together by the natural relations of resemblance (in part produced by the memory) and causation (only discovered by the memory). And consequently, leaving aside the fictions we invent, questions of personal identity are far too hazy to be answered with precision.

Section 7

Hume finishes Book 1 with a deeply skeptical interlude. Before continuing his accurate anatomy of human nature in Books 2 and 3, he anxiously ruminates: the danger of trusting his feeble faculties, along with the solitude of leaving behind established opinion, make his bold enterprizes look foolhardy. All his thinking is based on the seemingly... trivial principles of the imagination (the memory, senses, and understanding are, therefore, all of them founded on the imagination, or the vivacity of our ideas), which leave us so tangled up in irresolvable contradictions, and so dismayingly ignorant of causal connections. And how much should we trust our imagination? Here a dilemma looms: if we follow the imagination wherever it leads, we end up with ridiculous absurdities; if we follow only its general and more establish'd properties, we sink into total skepticism. As Hume writes: we have, therefore, no choice left but betwixt a false reason and none at all. Faced with this dilemma, we tend to just forget about it and move on, though Hume finds himself verging on an intellectual breakdown. Happily, human nature steps in to save him: I dine, I play a game of back-gammon, I converse, and am merry with my friends; and when after three or four hours' amusement, I wou'd return to these speculations, they appear so cold, and strain'd, and ridiculous, that I cannot find in my heart to enter into them any farther. And later, when he gets tir'd with amusement and company, his intellectual curiosity and scholarly ambition resurface and lead him back into philosophy. And since no human can resist reflecting on transcendent matters anyway, we might as well follow philosophy instead of superstition, for generally speaking, the errors in religion are dangerous; those in philosophy only ridiculous. In the end, Hume remains hopeful that he can contribute a little to the advancement of knowledge" by helping to reorient philosophy to the study of human nature—a project made possible by subjecting even his skeptical doubts to a healthy skepticism.

Book 2: Of the Passions

Part 1: Of pride and humility

Sections 1–6

Hume begins by recalling Book 1's distinction between impressions of sensation (original impressions, arising from physical causes outside the mind) and impressions of reflection (secondary impressions, arising from other perceptions within the mind), examining only the latter. He divides these reflective impressions—the passions, and other emotions resembling them—into "the calm and the violent (nearly imperceptible emotions of beauty and deformity, and turbulent passions we experience more strongly) and into direct and indirect" (depending on how complicated the causal story behind them is). Pride and humility are indirect passions, and Hume's account of the two is his leading presentation of the psychological mechanisms responsible for the indirect passions.

Since we cannot put the feeling of a passion into words, Hume identifies passions via their characteristic causes and effects. The cause of a passion is what calls up the passion: e.g., pride can be caused by one's beautiful house. A cause can be subdivided into the subject itself (e.g., one's house) and the quality of the subject that operates on the passions (e.g., the beauty of one's house). The object of a passion is what the passion is ultimately directed at: pride and humility are both directed at oneself. Both object and cause have a foundation in human nature: according to Hume, the object of these passions is fixed by the basic constitution of human psychology (Hume uses the term original), whereas their causes are determined by a more general set of adaptable psychological mechanisms (natural but not original).

Hume's account relies on three mechanisms. First, the association of ideas: the mind tends to move from one idea to another idea that is naturally related to it. Second, the association of impressions: the mind tends to move from one passion to another passion that resembles it in feeling (e.g., from joy to love). Third, their mutual assistance: if we feel a passion towards something, we will tend to feel a resembling passion towards something else naturally related to it (e.g., from anger at one person to impatience at a related person). Applying all this to pride, Hume argues that the pleasant sensation of pride, directed at ourselves, naturally tends to be called up when something naturally related to ourselves produces a pleasant sensation of its own. Likewise with humility: when something naturally related to ourselves produces an unpleasant sensation of its own, it tends to make us ashamed of ourselves. These indirect passions are thus the product of the double relation of impressions and ideas.

Hume completes his account with five limitations. First, in order for pride or humility to be produced, the relation of ideas must be a relatively close one. Second, because our judgments are strongly influenced by comparison, this relation must apply only to ourselves or a few others. Third, the cause of pride or humility must be something evident to ourselves and others. Fourth, this cause must be a long-lasting one. Fifth, general rules have a strong influence on our passions, leading us to overlook occasional anomalies.

Sections 7–10

In the next three sections, Hume puts his account to the test by examining three causes of pride and humility: the qualities of one's mind, of one's body, and of external objects. First, the qualities of the mind: our virtues and vices. Here Hume's main point is that, whatever the true nature of moral evaluation, whether it is a matter of innate moral psychology (Hume's own view), or instead self-interest and cultural training (the view of Hobbes and Mandeville), his account will hold up. For, on either theory, virtues produce a pleasant sensation of their own and vices a painful sensation of their own. Next come the qualities of the body: physical beauty and deformity. Here Hume's main point is that the beauty or deformity of something's structure is nothing more than its power to produce pleasure or pain in us. To the objection that though health and sickness produce pleasure and pain in us, they are not typically sources of pride or humility, he recalls that these passions require a long-lasting cause related only to ourselves or a few others—thus a long record of exceptionally poor health can in fact be a source of shame. Finally, Hume examines the qualities of external objects related to us. Though the natural relation of resemblance has little influence, he explains, external objects do not cause pride or humility without some relation of contiguity or causation—a fact he takes to confirm his overall account. After a few minor illustrations, Hume explains why pride in one's ancestors is magnified when the family enjoys uninterrupted possession of land, and when it is passed down from male to male (both of the conditions, he claims, serve to strengthen the relation of ideas).

Hume devotes an entire section to property and riches. His account easily accommodates property: he defines it as private use consistent with the laws of justice, contends that (whether justice be a natural or artificial virtue) our minds naturally associate owners with their belongings, and observes that all things useful, beautiful or surprising call up pride in their owner. But it is more difficult to accommodate riches: i.e., the mere power of acquiring the comforts of life. For Hume's earlier account of causation eliminated the distinction between power and the exercise of power, as well as the very idea of an unexercised power—and how can I take pride in mere coins and paper without such an idea? Hume finds two ways for something like unexercised power to influence our passions: first, predictions of human behavior are (absent strong motives) plagued with uncertainty, and we can receive anticipatory pleasure or unease from probable or merely possible exercise of power (tentatively reasoning from our own past conduct to guess what we might do); second, a false sensation of liberty presents all feasible courses of action as fully possible to us, giving us an anticipatory pleasure unrelated to any reasoning from experience. Hume finishes by noting the pride we take in power over others, a pride enhanced by comparing our condition to theirs (thus humans are prouder to own other humans than to own sophisticated machinery).

Sections 11–12

Hume's next section adds a new kind of cause of pride and humility: viz., reputation, a secondary cause grounded in the enormously important mechanism of sympathy. For Hume, sympathy with others, or communication, is that mechanism by which we naturally tend to receive and share in the passions and opinions of those we feel close to. We start by observing external signs (e.g., smiling or speaking) and forming an idea of another's sentiments. Since our extremely vivid conception of ourselves will tend to enliven any related idea, the closer the relation we see between ourselves and the other person, the more vivid our idea of their sentiments. And if this relation is close enough, we will end up actually feeling their passion or believing their opinion: i.e., our idea of their passion or opinion will grow so lively as to become the very passion or opinion itself. This mirrors Hume's earlier account of causal reasoning: both processes move along the three natural relations, channeling the force and vivacity of vivid perceptions into faint ideas, enlivening them into much stronger perceptions.

Pride or shame in one's reputation, Hume continues, stems primarily from the sympathetically communicated opinions of others. But additional factors play a role: others might be seen as a good judge of character (authority), and the very question of one's self-worth is both emotionally heightened and apt to evoke a self-conscious deference to the opinions of others. The resulting account explains various observations: why pride is affected more by the opinions of certain people (those whose character we like, whose judgment we respect, or who we have known for a long time), and less by opinions we know to be false (and thus cannot share in). Hume finishes by illustrating and confirming his account with a concrete example (viz., a man from a high-class family fallen on hard times leaving home to do manual labor elsewhere), and considering some minor objections.

In the final section, Hume seeks to confirm his overall account of pride and humility by applying it to animals. Following the model of anatomists, who test hypotheses by examining similar structures in humans and animals, Hume argues that animals can be observed to show pride and humility, that the causes are much the same (viz., pleasing qualities of the body), and that animals have the requisite psychological mechanisms (viz., the association of ideas, the association of impressions).

Part 2: Of love and hatred

Sections 1–3

Hume's treatment of love and hatred is much like his treatment of pride and humility: all four are indirect passions produced by a double relation of impressions and ideas. As Part 2 begins, he again distinguishes object from cause, and quality from subject; whereas pride and humility were directed at oneself, love and hatred is directed at some other person. As before, a relation of ideas is needed between the cause of love or hatred and the person loved or hated, and a relation of impressions between the cause (with a pleasant or unpleasant sensation of its own) and the resulting love or hatred. And since pride and love are closely connected (as Hume observes, we seek to win others' love by showcasing the qualities we take pride in), the arguments of Part 1 can simply be carried over.

In a series of eight experiments, Hume tests his account against observations drawn from ordinary life. The first four experiments simply confirm that the four indirect passions arise only in response to something pleasant or unpleasant related to some person: utterly neutral objects (e.g., an ordinary stone) and objects related to no one (e.g., an unfamiliar environment) will never produce pride or humility, love or hatred. The final four experiments focus on how easily a transition is made from one passion to another. As Hume's account would predict, we easily go from love and hatred to pride and humility: e.g., I can take pride in my relation to someone else with lovable qualities. Curiously, however, the reverse does not hold: e.g., my pride in my own qualities will not lead me to love someone else for their relation to me. To explain this, Hume argues that the imagination has trouble going from lively ideas to obscure ideas (e.g., from the idea of oneself to that of another person). Next, as Hume's account would also predict, we easily transition from love of one person to love of others related to this person. But the transition is easiest when we descend from the greater to the lesser: e.g., 'tis more natural for us to love the son upon account of the father, than the father upon account of the son. And yet the imagination has the opposite tendency: e.g., moving easily from Jupiter's moons to Jupiter itself. To resolve this difficulty, Hume argues that it is easier for the passions to make minor changes (adding in the love of a related lesser person) than major changes (adding in the love of a related greater person), and that the passions are a more powerful principle than the imagination. Finally, Hume acknowledges a case where we can move easily from pride to love: when the very cause of the pride and humility is plac'd in some other person, e.g. when your praise of me excites my pride and I end up loving you for it. But this exception only confirms Hume's account: since the first passion arises from the other person, we easily move to a passion directed at that same person.

Hume then confronts an objection: his account ignores intention, having us love or hate those who bring us pleasure or pain even where this is completely unintended. In response, Hume insists that qualities unrelated to intentional action really can elicit love or hatred, so long as the qualities are constant and inherent in someone's person and character: e.g., disliking someone for their ugliness or stupidity. It is with isolated actions that intention is important: it connects the action with the person and can also amplify the pleasantness or unpleasantness of the action, whereas entirely involuntary and accidental actions arouse only mild or short-lived passions. In a further illustration, Hume considers our emotional reaction to those who harm us from perfectly justified motives (e.g., judges, competitors): though we will not hate them if we are reasonable, we often hate them anyway, even inventing reasons to hate them.

Sections 4–5

In the next two sections, Hume uses sympathy to account for some particular causes of love and hatred. First, "relation, acquaintance, and resemblance: we sometimes love others not for their personal qualities, but simply because they are related to us, familiar to us, or similar to us. In these cases, pleasure arises from the sheer stimulating effects of sympathy: family members, neighbors, and acquaintances are a durable source of lively ideas, as are individuals with personal qualities resembling our own. And as Hume puts it, [e]very lively idea is agreeable, but especially that of a passion. He adds an explanation of why children feel far less related to mothers who remarry and yet only somewhat less related to fathers who remarry—the imagination (which finds a difficulty in passing from greater to less") is more inclined to go from the mother to the mother's new family than from the father to the father's new family, a transition which weakens the original parent-child relation.

Second, we sometimes esteem people not for their personal qualities, but simply for being rich and powerful (esteem and contempt being species of love and hatred). To account for this phenomenon, Hume identifies three candidate principles: (1) We enjoy thinking of their luxuries. (2) We think they might give us some of their wealth. (3) We sympathize with their happiness. He then argues that the third principle, sympathy, is by far the most important. The first principle has some influence on its own, but mostly operates by means of sympathy. And the second principle has little influence: it is relatively rare to receive any personal advantage from the rich and powerful, and we esteem them even when this is known to be impossible. Hume closes the section with an overview of the force of sympathy. Many animals, and especially humans, have a psychological need for social interaction. Moreover, sympathy with usefulness explains [m]ost kinds of beauty: e.g., the convenience of a house, the fertility of a field. Lastly, Hume observes that the minds of men are mirrors to one another: a rich man enjoys his luxuries, which brings esteem from others, which in turn excites the rich man's pride, which encourages further pursuit of riches.

Sections 6–12

The next six sections are dedicated to an examination of the compound passions, i.e. passions arising from the mixture of love and hatred with other emotions. Hume begins with benevolence and anger, motivational desires aimed at bringing about the happiness or misery of the person belov'd or hated. This marks an important contrast: love and hatred have innate motivational consequences, whereas pride and humility are only pure emotions in the soul. But Hume goes on to note that benevolence and anger are (despite the talk of mixture) not an essential part of love and hatred; instead, they are distinct passions of their own that only happen to be naturally conjoined with the sensations of love and hatred, just as hunger is naturally conjoined with an empty stomach.

Next come pity and malice. Like benevolence and anger, they are motivational desires aimed at bringing about another's happiness or misery; but unlike benevolence and anger, they apply quite generally—not only to those we love or hate, but even to complete strangers. Thus Hume calls them counterfeited versions of benevolence and anger. Pity (also called compassion) is received by sympathetic communication: anyone can arouse our pity, just by communicating their interests, their passions, their pains and pleasures to us. Even people who show no emotion at their misfortune can arouse our pity due to the influence of general rules on our imagination. Malicious joy is produced by comparison—[t]he misery of another gives us a more lively idea of our happiness, and his happiness of our misery—and malice itself is the unprovok'd desire of producing evil to another, in order to reap a pleasure from the comparison (though Hume adds a brief discussion of malice against ourselves). Hume also uses comparison to account for envy: the unpleasant feeling we experience when another's present enjoyment makes our own happiness seem diminished by comparison. He finishes the section by stressing the importance of a close relation of ideas: thus our envy tends to be confined to those in a similar line of work, a small horse seems more dwarfed by a large horse than by a mountain, and we gladly tolerate two adjacent paintings whose disparate styles would be monstrous if united in a single painting.

The following section sees Hume amending his account in response to a problem. If love and hatred are produced by anyone who brings us pleasure or pain, as Hume has argued, then we should love those who bring us malicious joy, and hate those who bring us the pain of pity. But this runs contrary to experience: we tend to hate the objects of our malice, and love the objects of our pity. Hume resolves this problem by introducing a new kind of relation of impressions: in addition to the resemblance of sensations, there is also the parallel direction of the desires. Thus the connection between pity and love, and between malice and hatred, lies in their motivational tendencies (which run parallel to each other), not in the way they feel (which run contrary to each other). Hume gives examples to illustrate and confirm this principle of a parallel direction, including a discussion of the emotions found in business rivals and business partners. But another problem arises: since Hume says we have esteem for the rich and contempt for the poor, how can he say we tend to love the objects of our pity? Hume's solution presents us with three levels of sympathy with misfortune: (1) weak sympathy, which makes us feel only the present misfortune of the afflicted, producing only contemptuous pity; (2) strong sympathy (i.e. double sympathy), which moves us beyond the present misfortune so that we take a motivating interest in their entire life, producing compassionate love; (3) all-consuming sympathy, which makes us fixate on the present misfortune, leaving us too overcome with horror to experience any other passions.

In the next section, Hume continues examining the compound passions, characterizing respect (also called esteem) as a mixture of love and humility and contempt as a mixture of hatred and pride: the qualities of others produce love or hatred immediately, pride or humility by comparison, and respect or contempt when these are joined together. And because we have a much stronger propensity to pride than to humility, there is more pride in contempt than there is humility in respect. Hume then acknowledges a problem: why, given his account, aren't love and hatred always accompanied by respect and contempt? His answer is that, whereas pride and hatred invigorate the soul and are associated with "magnificent objects, love and humility infeeble [the soul] and are associated with mean objects: thus lovable objects too mild to produce much pride (e.g., good nature, good humour, facility, generosity, beauty) will produce pure love, with but a small mixture of humility and respect". Hume finishes with an explanation of why social inferiors are expected to keep their distance from their superiors.

The final compound passion is the amorous passion, i.e. romantic love. It consists of three distinct passions: a sense of beauty, libido, and kindness. These three passions are bound together both by resemblance (all have a pleasant sensation) and by a parallel desire (all have related motivational tendencies). Accordingly, any one of them can end up producing the other two, with beauty most likely to produce the other two (kindness and libido being too remote from each other, and beauty plac'd in a just medium betwixt them). Hume argues that this phenomenon reinforces his double relation of impressions and ideas account.

Hume finishes Part 2 with his last section on animal psychology. Love and hatred, he writes, can be produced in animals simply by the pain or pleasure felt from an object, or by such relations as acquaintance and likeness of species. Sympathy works to spread feelings (e.g. fear, grief) from one animal to another, keep animal play from leading to injury, and animate a pack of hunting dogs beyond their individual level of excitement. In general, Hume remarks, the psychological mechanisms at work do not require any sophisticated force of reflection or penetration: [e]very thing is conducted by springs and principles, which are not peculiar to man, or any one species of animals.

Part 3: Of the will and direct passions

Sections 1–2

In Part 3, Hume begins examining the motives that bring us to action. After a glancing mention of the direct passions and a perfunctory definition of the will as a mere impression we feel, he confronts the hoary philosophical problem of free will and determinism, dedicating two sections to a defense of soft determinist compatibilism. In the first section, he makes a case for the doctrine of necessity. The issue, as Hume sees it, is whether human action is determined by a necessity comparable to "physical necessity—the necessity that governs physical objects. But since, according to Book 1, physical necessity is nothing more than constant conjunction and the causal inferences drawn by the human mind, the issue then comes down to this: is there a regular correspondence between human action and human psychology, and do we base causal inferences upon such regularities? Hume thinks the answer to both questions is obviously in the affirmative: the uniformity found in the world of human affairs is comparable to that found in the natural world, and the inferences we base on moral evidence" (concerning human psychology and action) are comparable to the inferences we base on natural evidence (concerning physical objects). Thus, given Hume's idiosyncratic account of necessity, it is hard to deny that human action is governed by necessity.

In the next section, Hume challenges the doctrine of liberty—the view that human beings are endowed with a distinctive kind of indeterministic free will—by setting out and debunking the reasons for [its] prevalence. First, since we confuse necessity with violent constraint, we end up confusing freedom from necessity (the indeterministic "liberty of indifference) with freedom from violent constraint (the compatibilist liberty of spontaneity). As a compatibilist, Hume accepts the latter kind of free will, deeming it that species of liberty, which it concerns us to preserve and even the most common sense of the word; but he rejects freedom from necessity as either absurd (being nothing more than sheer chance) or else unintelligible. Second, we are deceived by a false sensation of liberty: when deliberating about our own actions, there is a certain looseness to the will, so that we can easily produce an image or faint motion for each alternative course of action. Thus we end up convinced that we really could have acted differently, even though a spectator can commonly infer our actions from our motives and character. Finally, we mistakenly think necessity poses a threat to moral responsibility, and is therefore dangerous... to religion and morality". After noting that being dangerous is not the same as being false, Hume recalls that his necessity is a very attenuated one: there is nothing dangerous or even controversial about saying that constant conjunction and causal inference apply to human action as well as physical objects. He then attempts to turn the tables on his opponents, arguing that necessity is in fact essential to moral responsibility: the rewards and punishments of human law would be pointless if human action were not regular and uniform, and divine punishment would be unjust if a person's actions were a matter of sheer chance, lacking any causal connection to the person's psychology, and revealing nothing about the person's character. Thus the threat to moral responsibility comes not from necessity, but from indeterministic liberty.

Sections 3–8

Hume then passes from the will itself to the motivational factors that determine voluntary actions. Against the traditional view that reason and the passions frequently come into motivational conflict, Hume argues that reason is incapable of opposing the passions, and that the passions cannot run contrary to reason. First, reason alone cannot motivate us—it can only perform demonstrative or causal reasoning. And since abstract demonstrations influence us only by directing causal reasoning (e.g., doing math to pay your debts), and causal reasoning influences us only by directing preexisting motives (e.g., figuring out how to make the food you want), reason itself cannot bring about any motivation. And this in turn means it cannot counteract or regulate the passions: on the contrary, [r]eason is, and ought only to be the slave of the passions. Second, passions cannot be in agreement or disagreement with reason: for this is a matter of the agreement or disagreement between an idea and the object it represents, and passions do not represent anything else. Thus Hume notoriously writes: 'Tis not contrary to reason to prefer the destruction of the whole world to the scratching of my finger. Of course, if a passion is based on a false judgment—about an object that doesn't really exist, or a causal relation that doesn't really hold—then the passion can be considered unreasonable in a less strict sense of the term. But even then, insists Hume, 'tis not the passion, properly speaking, which is unreasonable, but the judgment. Finally, Hume argues that the alleged conflict between reason and the passions is actually a conflict between two different kinds of passions—the calm passions and the violent passions. Since both the calm passions and reason operat[e] with the same calmness and tranquility, we confuse them with each other and mistakenly suppose our calm passions to be determinations of reason.

The following five sections examine the factors which give passions their motivational force. Unsurprisingly, the violence of a passion makes it stronger; but even a calm passion can be extremely strong due to repeated custom and its own force, especially when it has been corroborated by reflection, and seconded by resolution. Nevertheless, since [g]enerally speaking, the violent passions have a more powerful influence on the will, Hume focuses on the factors which increase the violence of passions. First, when a predominant passion is accompanied by other inferior passions, it can acquire violence by swallow[ing them] up: e.g., strong love can be made more violently passionate by a touch of anger. Other psychological phenomena (e.g., opposition, uncertainty, obscurity) can produce the same effect by stimulating us with agitation and mental effort. Next, custom and repetition can both leave us with a direct inclination to perform the activity we are repeating and also affect the violence of related passions. Hume discusses three stages of repeated activity: (1) The sheer novelty of unfamiliar activities makes our feelings more intense, either magnifying our pain or adding on the pleasure of wonder [and] surprise. (2) An activity performed with moderate facility is an infallible source of pleasure (cf. flow), sometimes even converting pain into enjoyment. (3) But excessive repetition can make formerly pleasant activities so dull as to be unpleasant.

Our passions can also acquire violence from the vivacity of our ideas. Thus particular ideas make for more violent passions than general ideas,