The Philosophy Book

by DK Publishing

  The grounds for our belief that the sun will rise tomorrow, or that water rather than fruit will flow from a faucet, are not logical, according to Hume. They are simply the result of our conditioning, which teaches us that tomorrow the world will be the same as it is today.

  Inductive reasoning

  There are no surprises in Hume’s reasoning so far, but things take a strange turn when he applies this line of argument to inductive inference—our ability to infer things from past evidence. We observe an unchanging pattern, and infer that it will continue in the future, tacitly assuming that nature will continue to behave in a uniform way. For example, we see the sun rise every morning, and infer that it will rise again tomorrow. But is our claim that nature follows this uniform pattern really justifiable? Claiming that the sun will rise tomorrow is not a demonstrative statement, as claiming the opposite involves no logical contradiction. Nor is it a probable statement, as we cannot experience the sun’s future risings.

  The same problem occurs if we apply Hume’s fork to the evidence for causality. The statement “event A causes event B” seems on the face of it to be one that we can verify, but again, this does not stand up to scrutiny. There is no logical contradiction involved in denying that A causes B (as there would be in denying that 2 + 2 = 4), so it cannot be a demonstrative statement. Nor can it be proved empirically, since we cannot observe every event A to see if it is followed by B, so it is not a probable statement either. The fact that, in our limited experience, B invariably follows A is no rational ground for believing that A will always be followed by B, or that A causes B.

  If there is never any rational basis for inferring cause and effect, then what justification do we have for making that connection? Hume explains this simply as “human nature”—a mental habit that reads uniformity into regular repetition, and a causal connection into what he calls the “constant conjunction” of events. Indeed, it is this kind of inductive reasoning that is the basis of science, and tempts us to interpret our inferences as “laws” of nature—but despite what we may think, this practice cannot be justified by rational argument.

  In saying this, Hume makes his strongest case against rationalism, for he is saying that it is belief (which he defines as “a lively idea related to or associated with a present impression”), guided by custom, that lies at the heart of our claims to knowledge rather than reason.

  "Nature, by an absolute and uncontrollable necessity, has determined us to judge as well as to breathe and feel."

  David Hume

  Custom as our guide

  Hume goes on to acknowledge that although inductive inferences are not provable, this does not mean that they are not useful. After all, we still have a reasonable claim to expect something to happen, judging from past observation and experience. In the absence of a rational justification for inductive inference, custom is a good guide.

  Hume adds, however, that this “mental habit” should be applied with caution. Before inferring cause and effect between two events, we should have evidence both that this succession of events has been invariable in the past, and that there is a necessary connection between them. We can reasonably predict that when we let go of an object it will fall to the ground, because this is what has always happened in the past, and there is an obvious connection between letting go of the object and its falling. On the other hand, two clocks set a few seconds apart will chime one after another—but since there is no obvious connection between them, we should not infer that one clock’s chiming is the cause of the other’s.

  Hume’s treatment of the “problem of induction”, as this became known, both undermines the claims of rationalism and elevates the role of belief and custom in our lives. As he says, the conclusions drawn by our beliefs are “as satisfactory to the mind… as the demonstrative kind.”

  Science supplies us with ever more detailed information about the world. However, according to Hume, science deals with theories only, and can never yield a “law of nature.”

  A revolutionary idea

  The brilliantly argued and innovative ideas in the Treatise of Human Nature were virtually ignored when they were published in 1739, despite being the high-point of British empiricism. Hume was better known in his own country for being the author of a History of Great Britain than for his philosophy; in Germany, however, the significance of his epistemology had more impact. Immanuel Kant admitted to being woken from his “dogmatic slumbers” by reading Hume, who remained a significant influence on German philosophers of the 19th century and the logical positivists of the 20th century, who believed that only meaningful statements could be verifiable. Hume’s account of the problem of induction remained unchallenged throughout this period, and resurfaced in the work of Karl Popper, who used it to back up his claim that a theory can only be deemed scientific if it is falsifiable.

  "Hume was perfectly right in pointing out that induction cannot be logically justified."

  Karl Popper

  DAVID HUME

  Born in Edinburgh, Scotland, in 1711, Hume was a precocious child who entered the University of Edinburgh at the age of 12. Around 1729 he devoted his time to finding “some medium by which truth might be established”, and after working himself into a nervous breakdown he moved to La Flèche in Anjou, France. Here he wrote A Treatise of Human Nature, setting out virtually all his philosophical ideas before returning to Edinburgh.

  In 1763 he was appointed to the Embassy in Paris, where he befriended the philosopher Jean-Jacques Rousseau and became more widely known as a philosopher. The controversial Dialogues Concerning Natural Religion occupied Hume’s final years and, because of what he called his “abundant caution”, were only published after his death in Edinburgh in 1776.

  Key works

  1739 A Treatise of Human Nature

  1748 An Enquiry Concerning Human Understanding

  1779 Dialogues Concerning Natural Religion

  See also: Plato • Aristotle • René Descartes • John Locke • George Berkeley • Immanuel Kant • Ludwig Wittgenstein • Karl Popper

  IN CONTEXT

  BRANCH

  Political philosophy

  APPROACH

  Social contract theory

  BEFORE

  1651 Thomas Hobbes puts forward the idea of a social contract in his book Leviathan.

  1689 John Locke’s Two Treatises of Government asserts a human’s natural right to defend “life, health, liberty, or possessions.”

  AFTER

  1791 Thomas Paine’s Rights of Man argues that government’s only purpose is to safeguard the rights of the individual.

  1848 Karl Marx and Friedrich Engels publish The Communist Manifesto.

  1971 John Rawls develops the idea of “Justice as Fairness” in his book A Theory of Justice.

  Rousseau was very much a product of the mid- to late- 18th-century period known as the Enlightenment, and an embodiment of the continental European philosophy of the time. As a young man he tried to make his name as both a musician and composer, but in 1740 he met Denis Diderot and Jean d’Alembert, the philosopher compilers of the new Encyclopédie, and became interested in philosophy. The political mood in France at this time was uneasy. Enlightenment thinkers in France and England had begun to question the status quo, undermining the authority of both the Church and the aristocracy, and advocates of social reform such as Voltaire continually fell foul of the overbearing censorship of the establishment. Unsurprisingly in this context, Rousseau’s main area of interest became political philosophy. His thinking was influenced not only by his French cont
emporaries, but also by the work of English philosophers—and in particular the idea of a social contract as proposed by Thomas Hobbes and refined by John Locke.

  Like them, Rousseau compared an idea of humanity in a hypothetical “natural state” with how people actually live in a civil society. But he took such a radically different view of this natural state and the way it is affected by society, that it could be considered a form of “counter-Enlightenment” thinking. It held within it the seeds of the next great movement, Romanticism.

  Science and art corrupt

  Hobbes had envisaged life in the natural state as “solitary, poor, nasty, brutish, and short.” In his view humanity is instinctively self-interested and self-serving, and that civilization is necessary to place restrictions on these instincts. Rousseau, however, looks more kindly on human nature, and sees civil society as a much less benevolent force.

  The idea that society might be a harmful influence first occurred to Rousseau when he wrote an essay for a competition organized by the Academy of Dijon, answering the question: “Has the restoration of the sciences and the arts contributed to refining moral practices?” The expected answer from thinkers of the time, and especially from a musician such as Rousseau, was an enthusiastic affirmative, but in fact Rousseau argued the opposite case. His Discourse on the Sciences and Arts, which won him first prize, controversially puts forward the idea that the arts and sciences corrupt and erode morals. He argues that far from improving minds and lives, the arts and sciences decrease human virtue and happiness.

  The Romantic movement in art and literature that dominated the late 18th and early 19th centuries reflected Rousseau’s vision of the state of nature as one of beauty, innocence, and virtue.

  The inequality of laws

  Having broken with established thinking in his prize-winning and publicly acclaimed essay, Rousseau took the idea a stage further in a second essay, the Discourse on the Origin and Foundations of Inequality among Men. The subject matter chimed with the mood of the time, echoing the calls for social reform from writers such as Voltaire, but once again Rousseau contradicted conventional thinking with his analysis. The selfish, savage, and unjust state of nature depicted by Hobbes is, for Rousseau, a description not of “natural man”, but of “civilized man.” In fact he claims that it is civil society that induces this savage state. Humanity’s natural state, he argues, is innocent, happy, and independent: man is born free.

  Society corrupts

  The state of nature that Rousseau describes is a pastoral idyll, where people in their natural state are fundamentally good. (The English wrongly interpreted Rousseau’s idea of natural man as a “noble savage”, but this was due to a mistranslation of the French sauvage, which means simply “natural”, not brutish.) People are endowed with innate virtue and, more importantly, the attributes of compassion and empathy. But once this state of innocence is disrupted, and the power of reason begins to separate humankind from the rest of nature, people become detached from their natural virtues. The imposition of civil society on the state of nature therefore entails a move away from virtue toward vice, and from idyllic happiness toward misery.

  Rousseau sees the fall from a state of nature and the establishment of civil society as regrettable but inevitable, because it resulted from the human capacity for reason. The process began, he thought, the first time that a man enclosed a piece of land for himself, so introducing the notion of property. As groups of people began to live side by side like this, they formed societies, which could only be maintained though a system of laws. But Rousseau claims that every society loses touch with humanity’s natural virtues, including empathy, and so imposes laws that are not just, but selfish. They are designed to protect property, and they are inflicted on the poor by the rich. The move from a natural to a civilized state therefore brought about a move not only from virtue to vice, Rousseau points out, but also from innocence and freedom to injustice and enslavement. Although humanity is naturally virtuous, it is corrupted by society; and although man is born free, the laws imposed by society condemn him to a life “in chains.”

  Adam and Eve represent the kind of perfect “natural” humans that Rousseau thought predated society. He said that we, like them, are corrupted by knowledge, becoming ever more selfish and unhappy.

  The Social Contract

  Rousseau’s second Discourse ruffled even more feathers than his first, but it gained him a reputation and quite a following. His portrayal of the state of nature as desirable and not brutal formed a vital part of the emerging Romantic movement in literature. Rousseau’s rallying cry of “back to nature!” and his pessimistic analysis of modern society as full of inequalities and injustices sat well with the growing social unrest of the 1750s, especially in France. Not content with merely stating the problem, Rousseau went on to offer a solution, in what is seen as perhaps his most influential work, The Social Contract.

  Rousseau opens his book with the challenging declaration “Man is born free, yet everywhere he is in chains”, which was considered such a call for radical change that it was adopted as a slogan during the French Revolution 27 years later. Having issued his challenge, Rousseau then sets out his vision of an alternative civil society, run not by aristocrats, the monarchy, and the Church, but by all citizens, who participate in the business of legislation. Modelled on Classical republican ideas of democracy, Rousseau imagines the citizen body operating as a unit, prescribing laws according to the volonté générale, or general will. The laws would arise from all and apply to all—everyone would be considered equal. In contrast with the social contract envisaged by Locke, which was designed to protect the rights and property of individuals, Rousseau advocates giving legislative power to the people as a whole, for the benefit of all, administered by the general will. He believes that the freedom to take part in the legislative process would lead to an elimination of inequality and injustice, and that it would promote a feeling of belonging to society—that it would inevitably lead to the liberté, égalité, fraternité (liberty, equality, fraternity) that became the motto of the new French Republic.

  "Tranquility is found also in dungeons; but is that enough to make them desirable places to live in?"

  Jean-Jacques Rousseau

  The evils of education

  In another book written in the same year, entitled Emile, or On Education, Rousseau expanded on his theme, explaining that education was responsible for corrupting the state of nature and perpetuating the evils of modern society. In other books and essays he concentrated on the adverse effects of both conventional religion and atheism. At the center of all his works lay the idea that reason threatens human innocence and, in turn, freedom and happiness. Instead of the education of the intellect, he proposes an education of the senses, and he suggests that our religious faith should be guided by the heart, not the head.

  "The general will should come from all to apply to all."

  Jean-Jacques Rousseau

  Political influence

  Most of Rousseau’s writings were immediately banned in France, gaining him both notoriety and a large following. By the time of his death in 1778, revolution in France and elsewhere was imminent, and his idea of a social contract in which the general will of the citizen body controlled the legislative process offered the revolutionaries a viable alternative to the corrupt system as it stood. But his philosophy was at odds with contemporary thinking, and his insistence that a state of nature was superior to civilization led him to fall out with fellow reformers such as Voltaire and Hume. Rousseau’s political influence
was felt most strongly during the period of revolution immediately after his death, but his influence on philosophy, and political philosophy in particular, emerged to a greater extent in the 19th century. Georg Hegel integrated Rousseau’s ideas of social contract into his own philosophical system. Later and more importantly, Karl Marx was particularly struck by some of Rousseau’s work on inequality and injustice. Unlike Robespierre, one of the leaders of the French Revolution, who had appropriated Rousseau’s philosophy for his own ends during the Reign of Terror, Marx fully understood and developed Rousseau’s analysis of capitalist society and the revolutionary means of replacing it. Marx’s Communist Manifesto ends with a nod to Rousseau, encouraging the proletarians (workers) have “nothing to lose but their chains.”

  The French Revolution, which began 11 years after Rousseau’s death, was inspired by his claim that it was unjust for the rich few to rule over the effectively voiceless, powerless poor.

  JEAN-JACQUES ROUSSEAU

  Jean-Jacques Rousseau was born to a Calvinist family in Geneva. His mother died only a few days after his birth, and his father fled home following a duel a few years later, leaving him in the care of an uncle.