In the epilogue of his very well-written biography, under the heading “The Afterlife of Diderot,” Mr. Furbank complains about the definite article in the English phrase “The Enlightenment”: a phrase that distorts the thought of eighteenth-century philosophy and that is particularly a barrier to understanding, and celebrating, Diderot. A false unity is implied, traceable, he thinks, to its origin in Ernst Cassirer’s The Philosophy of the Enlightenment, which set a fashion for countless histories of ideas. Up to the present day, conservatives have too blandly assimilated very diverse thinkers to a common pattern as all apostles of Reason in politics.

Of the great triumvirate of the century in France—Voltaire, Rousseau, Diderot—only Voltaire can possibly be represented as exalting rationality in morals and politics, and even he appealed more often to common sense and to the observation of nature. Rousseau and Diderot made natural sentiments and emotions the center of their moralities and left logic and reasoning, in any strict sense, on the periphery. For conservative pamphleteers, now as in the last century, it has been easier to lump them all together to form a single target and to denounce a false notion of philosophical rationality as responsible for the September massacres during the French Revolution, and even for the later excesses of totalitarian planning.

Like so many arguments drawn from the history of ideas, this one is superficially plausible only in so far as it is kept vague and remote from specific texts. As joint editor with D’Alembert of the Encyclopedia, the great monument of advanced thinking in the eighteenth century, Diderot gets caught up in this controversy because several contributors to the Encyclopedia, who were also his friends, were indeed utilitarians and rational optimists in philosophy, and some of them also believed in scientific determinism and in the dawn of a new age of harmony and peace: Condorcet, Helvétius, Condillac, Holbach, La Mettrie, did believe, with different emphases and for different reasons, that their new theories of knowledge would enable humanity to be remodeled for the benefit of all in a splendid future.

Diderot certainly had no such confidence. He argued that the human sciences were still in their infancy and that we still know almost nothing about the workings either of the mind or of the brain or of their relation to each other. He often wrote and spoke of the vast range of different possibilities open to men and women and of new forms of happiness that would unpredictably arise. Famously he evoked in his dialogue Le Neveu de Rameau the ambiguities, the uncertainties, and incoherences which the contrast of virtue and vice, and any conventional ethics, always entails.

Diderot neither sought nor achieved purity of soul either in his life or in theory. He was amused by his own inconsistencies and weaknesses, as we know from his letters to Sophie Volland, at one time his mistress: letters still wonderful to read, comparable with the letters of Keats or Byron. When in prison, as he was on two occasions, or later threatened with prison for subversion, he did not try to be a hero. He was ready for every compromise and concession. He did not believe in perfectibility or acknowledge the idea of the good. In Le Neveu de Rameau he dramatizes the destructive element, the play-acting and the role reversals, which are no less natural in men and women than honesty and good feeling. Sincerity, in his view, could not be a cardinal virtue, because creativity is closely linked to mixed intentions and to confusions of identity.

Denis Diderot was born in 1713 in the still beautiful, and very provincial, town of Langres, the son of a cutler, whom he deeply loved and admired and who was able to send him to study in Paris in 1729. He often returned there and died there in 1784. Diderot from the beginning rejected the Church and despised intolerance and piety, and he rejected chastity as an ideal. He began his literary career with a rather feeble and mildly pornographic story, Indiscreet Jewels, which he published after his translation of Shaftesbury’s Inquiry Concerning Merit and Virtue and his own immature Pensées Philosophiques. In the mid-1740s he began work on a vast and glorious project, glorious in its own time and still of interest now, the Encyclopedia. Diderot was always preoccupied with glory, fame, and immortality, debating their value with himself and in his letters to friends. Why should one care so much about posthumous fame and glory? Does not happiness consist principally in the admiration of one’s family and friends? The Encyclopedia was intended to bring glory to him and to France.

The Encyclopedia of the Arts and Sciences was to take the place of a French translation of the Cyclopaedia, or Universal Dictionary of the Arts and Sciences published by Ephraim Chambers, a Scotsman, in 1728. Chambers had produced a mere work of reference, an inert catalog of names and facts without theme or inspiration. Diderot’s Encyclopedia was to make a statement about the expanding domain of human knowledge, its present frontiers and future possibilities. The great empire of the new sciences and applied arts called for a charter and a written constitution, and this was the time, the 1740s, for a many-volumed manifesto summarizing its numerous conquests and their mutual dependencies.


Diderot’s fellow editor was his close friend, the internationally celebrated mathematician D’Alembert, a forthright atheist and free-thinking wit, who dominated the salons of Madame du Deffand and Madame Geoffrin, and later was the lover of Julie de l’Espinasse, whose house became the house of friendship for the free-thinkers of Paris. Unlike D’Alembert, Diderot throughout his life was capable of some pliancy in the face of the authorities, and his prospectus for the Encyclopedia made a successful patriotic appeal to the chancellor, the licensing authority. Explicit mockery of the Church and of Christian theology was never to be prominent in Diderot’s own contributions, even though the whole enterprise was unavoidably radical and subversive. Its editors were always liable to be imprisoned or otherwise punished.

For two decades Diderot walked a tightrope as chief editor, restraining himself and his contributors from any blatant attacks on the Church or the monarchy. He even printed some grave discussions of Christian thought. But he did fall off his tightrope early in his life on a famous occasion. His first serious philosophical work, Pensées Philosophiques, was burned by the public hangman, a common procedure at the time, because it was obviously the work of a dangerous freethinker. In 1749 he published Lettre sur les aveugles, an empiricist’s essay, and he was immediately arrested and imprisoned in the Castle of Vincennes, where his wife joined him and Rousseau visited him, and he continued to read voraciously, as he always did, wherever he might be.

But he was a man who could not bear the stillness and repose of prison life, with its uniformity and predictability. He always needed movement, impulsive starts and stops, contrasts and contradictions in conversation and argument, constant talk and social variety. There were fears that he would go mad in confinement, and, once interrogated, he humbly confessed his guilt, abjured his evil opinions, and revealed the names of his printers.

Thereafter he was released and wrote Lettre sur les sourds et les muets (Letter on the Deaf and the Mute), his second clever essay on the theory of knowledge. Exaggerating the empiricism of John Locke, who had denied that there could be innate ideas independent of experience and perception, Condillac in his Traité des sensations had traced all knowledge back to its alleged foundation in the association of ideas, which had their origin in the separate senses of sight, touch, and hearing. But how are the data of the separate senses coordinated to form some stable and coherent picture of the external world? Is there not an assumption of a unitary self which coordinates? Against Condillac and the pure empiricists, the so-called “sensualist philosophy,” Diderot was always to insist that it is of the nature of mind to be active in its interaction with the external world, and that it is bad philosophy to represent our minds as just passive and receptive in perception—as empty buckets. This, he held, could not be true of any organism in the natural order.

Mr. Furbank’s biography of Diderot is light and sympathetic in a style appropriate to its subject, and he makes no attempt at any systematic exposition of Diderot’s thought. Diderot himself was unsystematic, his biographer remarks, and this is plainly true. Also writing was not the center of his life, which revolved around his family, his friendships, and his love affairs, the Encyclopedia, and the pursuit of pleasure in society. His most famous and serious works—Le Rêve de D’Alembert, Le Neveu de Rameau, Entretien entre Diderot et D’Alembert, Paradoxe sur le Comédien, Supplement au voyage de Bougainville—were not published in his lifetime, and he worked on them casually and at intervals, and for his own satisfaction and the edification of his friends.

Mr. Furbank stresses the innovations of form in his philosophical writing which are to be explained by the tentative, wholly speculative, and undogmatic positions which he took up. He habitually used the dialogue form, which enabled him to evade stating any final conclusions of his own. The topic had been opened and thereafter the talk should continue—that was the design. In the course of his dialogues he attributed views to friends and contemporaries (Condillac, D’Alembert, a famous doctor Théophile Bordeu, Mlle. de l’Espinasse, Rameau’s nephew) which were not his, but they were arguable and were among the principal strands in modern thought. He did not mind contradicting himself between one work and another. Apart from any changes and development in his philosophy, the different contexts of argument were meant to explain why he rejected free will in one place and why in another place he rejected determinism applied to human actions and beliefs.


Determinism was one of the many issues on which he followed Spinoza. The multiplicity of causes in the common order of nature, he argued, is inexhaustibly complex and, for all human purposes, determinism is therefore irrelevant to our lives and to our morals. Successes and failures, particularly in the arts, present themselves to us as matters of chance as much as of skill. On the other hand if belief in free will is the belief that persons are originating causes, it is an illusion and a harmful illusion. You can dissolve the apparent contradiction between free will and determinism if, and only if, you always remember that human knowledge, and particularly self-knowledge, is pathetically limited, and that it always will be.

Mr. Furbank has chapters on The Letter on the Blind, and on the Encyclopaedia, on the novels The Nun and Jacques the Fatalist, and on the best known and most influential of the dialogues, Rameau’s Nephew, and D’Alembert’s Dream. For Diderot, as Mr. Furbank’s narrative shows, writing was an extension of talking. Sometimes the talk was a monologue rather than a conversation, as in the early philosophical treatises “Philosophic Thoughts,” and “On the Interpretation of Nature.” Even there the sentences drift forward in the loose and informal manner of a lecturer or popular journalist, not in the magisterial manner of Leibniz or Voltaire. Diderot intends his readers to “picture the movements and march of his mind,” and not only to picture but to participate in the movement. That is what he meant when he said that he was the most “communicative” of men. It was part of his theory of knowledge, repudiating the mighty authority of Descartes, that truth emerges in the flash and friction of conversation, typically around a dinner table, rather than in the detached soul of a solitary thinker sitting by a stove and interrogating his own mind. At least in the realm of natural philosophy and metaphysics, truth is a social construction. His image of intelligence is not Rodin’s heavy and immobile Penseur, but rather the fluid and variegated outlines of the figures in Raphael’s School of Athens.

The reason for this anti-Cartesian conception of thought is to be found in Diderot’s philosophy of nature. For Descartes, still a Christian philosopher, the individual human soul or mind stands outside, and above, the natural order, to which it is attached only by its association with a body. Hence the splendor and majesty of the declaration Cogito, ergo sum: my unique existence as a thinking creature is known, but known not through any of the fallible channels of natural knowledge. When we are thinking, and thinking methodically, Descartes and you and I are transcendent beings, not caught up in the accidents and complexities of the natural order, which we loftily observe and inquire into.

Diderot reversed this metaphysics consistently and Spinozistically in all his writings, including in his fiction and in his moral speculations. His deepest conviction, the clue to his own way of life as well as to his art and thought, was that human beings are inextricably parts of nature (which he called le tout) and, physically and mentally, are subject to all its unpredictable contingencies. This is the kernel of what was later called his materialism, and it was this so-called materialism that made him one of the saints in the old Marxist calendar. But it was a materialism with a difference, not the reductive, rather lumpish materialism of his contemporaries La Mettrie, Baron Holbach, and others, which survived throughout the nineteenth century and which flourishes among the computers in Australia and in the US even today.

The second aspect of Diderot’s materialism was his passionate interest in the applied arts and in technology and in all forms of craftsmanship. He loved to explain how elementary machines worked, for example, in the printing trade and to find good illustrations of their workings. This passion, as much as philosophy, was the inspiration of the Encyclopedia: an interest in concrete causes in place of spiritual mysteries was characteristic of the French Enlightenment, so different from the German, and the Encyclopedia was the instrument of this new light.

There were to be seventeen volumes of the Encyclopedia and Diderot needed twenty-one years (1751–1772) to complete his editorial labor, sometimes working ten hours a day. He himself contributed a great variety of articles, about twenty on philosophical subjects, and even more on applied arts and crafts. The whole was a campaign of demystification with a clear Baconian aim: disseminated knowledge would be disseminated power, and modern minds would be opened up to the real resources of the modern world, after the long sleep in the darkness of ecclesiastical ignorance. Material improvement came before spiritual gains. A consequence of Diderot’s materialism was that the beauty and wisdom in a craftsman’s work is not to be ranked lower, as a natural achievement, than abstract speculation, as Plato had required, or as mathematicians, including D’Alembert, still insisted. Mr. Furbank quotes Diderot:

In what physical or metaphysical system do we find more intelligence, discernment, and consistency than in the machines for drawing gold or making stockings, and in the frames of the braid-makers, the gauze-makers, the drapers, or the silk workers? What mathematical demonstration is more complex than the mechanism of certain clocks or the different operations to which we submit the fibre of hemp or the chrysalis of the silkworm before obtaining a thread with which we can weave?

This is pure Diderot in its love of the concrete and the mundane. In its perception of the beauty of instruments, the passage is typical of the new sensibility of his century, the sensibility of the amateur experimentalist, illustrated in England by Wright of Derby. Diderot celebrated the glory of productive processes and of the mastery of preindustrial skills, with the clock-maker coming nearer to God’s work than the metaphysician. He loved the variety and the jagged intricacy of instruments. He had wanted to be an inventor himself and he had plans for a kind of typewriter, a new instrument on which a person could compose, even a design for an encoding machine.

But his co-editor, D’Alembert, wrote the preliminary discourses, subsequently famous, which set forth the proper scheme of the sciences, glorifying mathematics as the pinnacle, while Diderot wrote a prospectus for subscribers which based distinct disciplines on three distinct faculties of the mind—memory, reason, and imagination. Although they began as very close friends, and although Flaubert was later to remark irritably that one seemed never to be mentioned without the other, the two editors in fact had largely different philosophies, and different plans for the future of humanity. D’Alembert was a rationalist in every sense of the word, and thought of Nature as submitting to our understanding under natural laws mathematically expressed: physics was for him the basic science. Mr. Furbank quotes a typical D’Alembert doctrine: “Obscurity invades our ideas of an object in proportion as we study more of its sensible properties.” Again: the Universe, for someone who was able to take it in as a whole from a single standpoint, would appear, if one may so put it, as a unitary fact and a single great truth—an anticipation of Laplace.

In “Of the Interpretation of Nature” Diderot launched an attack on the dominance of mathematics in the natural science of his time.

We are just coming to a great revolution in the sciences. In the inclination that intellects [les esprits] have toward ethics, literature, natural history, and experimental physics, I would be bold enough to guarantee that in less than a century one will not count three great geometers in Europe.

In a famous letter to Voltaire in 1758 he wrote: “The reign of mathematics is no more. Taste has changed. It is now the hour of natural history and belleslettres,” and he insisted that D’Alembert’s thought was mired in the past. Biology, and the study of organic processes, was to be the dominant science.

Mr. Furbank explains how alongside the clash of philosophies there were personal reasons for the final break. D’Alembert resigned as editor and left Diderot alone to evade and cajole the censor, to find the myriad illustrations needed, and to write himself the articles which had been promised by contributors and which were still unwritten.

Diderot had the flair and the fluency of a born journalist, shamelessly plagiarizing secondary authorities rather than leaving a gap unfilled, and aiming always at readability, sometimes by introducing names of persons to make technical issues more memorable and more dramatic. What was later to be known as the higher journalism has one of its origins in the Encylopedia, although its select subscribers did not compare in numbers with Hazlitt’s public or with that of The Quarterly Review. The subscribers were a tiny group of princes and aristocrats. The unique genius of Diderot was to combine, on the same level of seriousness, the metaphysics of Spinozism with a technical analysis of handloom weaving. Having dethroned mathematics from its position as the paradigm of all knowledge, Diderot lost interest in the Cartesian boundary that had been supposed to divide, cleanly and clearly, the works of the intellect from the works of the imagination. Parts of nature ourselves, we can reconstruct natural processes of development, and come to understand them in several different ways, sometimes through artistic constructions, and through formal experiments in the arts, no less than through the observations and generalizations of physiology and of physics.

In his famous Salon, a periodical review of recent paintings exhibited in the Louvre, Diderot introduced discriminations between true and false, authentic and inauthentic, in the art of painting. In his “On the Interpretation of Nature,” or in his treatise on physiology, he distinguished between authentic and inauthentic science. In both cases one must first rid one’s mind of the idea of truth as essentially a matching of thought to external reality. The greatness of Chardin’s paintings resides in the invented naturalness of the forms, which are not a triumph of piecemeal copying, but rather show a genius in tracing a whole pictorial structure that has suggested itself to the artist, he knows not how, as natural and fitting for this particular subject. Through true artistic invention, in art and in fiction, we may come to participate in the processes and forms of nature through an affinity and a sympathy that can never be further explained. In the art of painting we first invent, and thereby discover, an analogy for the mixed moods of the sea and for the relations between colors, shapes, and surfaces.

Diderot throughout his life was preoccupied with the notion of genius, not only in his classic treatment of its destructiveness in Le Neveu de Rameau, but in application to his own insights. Mr. Furbank quotes him as suffering “from a violent desire to discover, to invent…. ” For fifty years he had waited in vain for “the happy chance” that would entitle him to call himself a genius. His genius, it finally emerged, was in the immense variety and range of his thought as short-story writer, novelist, art critic, philosopher, scientist, dramatist, moral philosopher.

When one thinks of Diderot and of his philosophy, it is always appropriate to think first of conversation and of discussions among friends. In composing the Salon, no less than in his correspondence with friends, he remains informal and discursive and delightedly chases after irrelevancies if they are intellectually amusing. One never knows when a speculation may turn out to be suggestive and productive. He liked his work to be a series of sketches, dashed off at different times, and not marmoreally composed. His life also was not composed and was not all of a piece. His writing was to be an expressive part of his life, showing the natural movement of his mind: a fluent and multidirectional movement, not chopped up into hard and wellmarked fragments like Voltaire’s. He was before all things an inspired talker, both by nature and on principle. In Le Rêve de D’Alembert, the doctor Bordeu and Julie de l’Espinasse each exhibit their own perspective and their foibles and sensitivities: the formality of assertion and counter-assertion is softened and dissolved.

Socrates was for Diderot the supreme and immortal hero of thought, but the gossipy, free-for-all, intellectually uncertain quality of Diderot’s two great dialogues is a long way from Socrates’ measured speech in his dialogues: they are in a particular eighteenth-century style, neither neoclassical nor academic. Mr. Furbank quotes Taine on Diderot:

Forgetting himself, carried away by his own story, listening to inward voices, taken by surprise by reports which come to him unawares, he has said everything on Nature, Art, ethics in two little works [Le Rêve de D’Alembert and Le Neveu de Rameau] of which twenty successive readings will not lessen the charm or exhaust the significance…. There lies the advantage of these geniuses who do not have empire over themselves.

Diderot cultivated his spontaneity and the inspiration of the moment. He wanted to be the exemplary dilettante of genius, experimenting with his own identity, an example that Stendhal was to follow when he addressed himself in his Journals by different names. Diderot was happiest in a group of free-thinking disputants—typically, in Baron d’Holbach’s country house—when he and his friends, “felt free to utter whatever came into their minds.” In his brilliant dialogue Le paradoxe sur le Comédien (The Paradox of the Actor), one character is the man of feeling who loses his head and only recovers it at the bottom of the stairs (l’esprit d’escalier). But the other character is the calm and detached actor who stands apart from the emotion which he carefully enacts.

Like Lichtenberg writing about Garrick, Diderot sees in acting an exaggeration of the duality of the self and of multiple personalities, which he takes to be the normal conditions of human wholeness. It is natural to enter into dialogues and disputes with others because it is natural first to enter into disputes with oneself. The mind works by contradiction. That is why in Le Neveu de Rameau there are the characters Moi and Lui. In a person’s inner life actors move on a crowded stage where contrary passions come and go, masked and in disguise.

Scientific theory and fiction were equally interpretations of Nature for Diderot. La Religieuse (The Nun), posthumously published, is the greatest of his pure fictions. It was written to deceive a friend who, in a cruel and unpleasant hoax, was meant to take the story as a true story and to try to rescue the heroine. He was in fact deceived. Recounting this episode Mr. Furbank is remarkably uncensorious, perhaps because this kind of cruel mockery of the feelings of friends was accepted as normal in its day.

Diderot continued to work at intervals on the novel, which developed into a vivid and subtle study of passion uncontrolled, a lesbian passion in which maturity and innocence are brought into conflict. As a philosophical materialist, always at war with Descartes’s mind-body dualism, sexuality and physical passion are for Diderot the central knot of personality, where self-awareness and sensuality are intertwined. Society’s efforts to confine sexuality within general rules and conventions will, he wrote, often end in disaster. This moral is elaborated in the dialogue Supplément au voyage de Bougainville, which compares the generous and philoprogenitive sexuality of the Tahitians, who are free from all possessiveness, with the jealous and stifled impulses of a visiting Christian gentleman. On the whole the Tahitians in their arcadia come out better than the damp and inward-looking Christians, who admittedly have an advantage in learning, but have lost their feeling for natural happiness.

But Diderot was not committed to a naive dichotomy between natural impulse and the thoughtful artificialities of high culture, which is sometimes implied in Rousseau’s “Discourse on Inequality.” Human beings for Diderot are by nature comedians, poseurs, prone to art and to artificiality, and their impulses are not simple and uncorrupted by circumstance. Any return to nature is also a return to conflicts and to contradiction. The power of reflection and thought is part of the nature of organisms which are as complex in structure as human beings and which are also pliable and adaptable, each in a singular way. We shall therefore encounter possessive and imprisoning passions, like that of the Mother Superior in The Nun, as naturally as the passions that are associated with liberation and with escape from repression. The opposition between good and bad is not between Nature and Civilization, two universals, but always between happy and unhappy adaptations of individuals to their particular surrounding conditions. When individual natures are in harmony with the particular conditions to which they are responding, then happiness supervenes: as Diderot himself was happy when plotting his publications with Grimm in Madame d’Epinay’s garden, or arguing with Abbé Galiani at dinner with the Baron D’Holbach, or making a philosophical point in a letter to his lover Sophie Volland, or at home with his daughter Angélique, or in his conversation at any hour of day or night with the Empress Catherine in St. Petersburg.

In the spirit of Montaigne, Diderot took it to be evident that the soul, or self, was in constant flux, transforming itself just as the cells of the body are constantly changing within a constant structure. His favorite image of identity, and particularly of personal identity, was a swarm of bees, which holds together and preserves its identity in the way that a human personality, with its myriad thoughts and sensations, still holds together. We can distinguish within the swarm of any individual’s memories and passions the contrary desires and conflicting beliefs that keep the swarm alive and in motion. Diderot’s moral and aesthetic attitudes, and even the direction of his own life, depended upon this doctrine of the insubstantial self as well as on his materialism. The integrity of a person was like the integrity of the swarm, and not that of a block of marble, a material that he particularly disliked. “Marble does not laugh.”

According to Spinoza’s materialism, human beings perceive and interpret nature, including human nature, in two distinct ways: teleologically, in terms of desires, beliefs, and the self-conscious pursuit of ends; mechanically, in terms of laws of motion. Nature (“the whole”) is inexhaustible and forever exceeds our knowledge and understanding. The duality of the two orders resides in us as embodied observers. Observing the plucking of the strings of a musical instrument, I may attend to the physical motions occurring or I may attend to the tune: the same event in the natural order, but different interests.

This is Diderot’s example. As a theorist of portrait painting and of dramatic art and of sculpture, and a theorist also of sexuality, Diderot recognized that human bodies, unlike machines, are visibly animated by changing thoughts and passions: he was always thinking, as a novelist, dramatist, art critic, and physiologist, of the changing expressions in a person’s eye, the tone of a voice, the harmony of colors of fruit and glass on a table in a Chardin, the thought that entered into the sculptor Falconet’s carving and molding. Blind and deaf persons are compelled to think more abstractly. For purposes of explanation, as physicists and physiologists, we also need to think more abstractly, looking for laws and generalities. But we talk with whole persons, irreducibly singular, and we find friendship, and therefore happiness, in noticing and dwelling on particularities—particularities of place and of the countryside as well as of persons.

Diderot took his place in the line that passes from Democritus through Lucretius to Spinoza, and that Marx sometimes, and in spite of his Hegelian obfuscations, claimed to continue. Philosophy was for all of them demystification; they were the metaphysicians of fearlessness, who refused to be haunted by anything that could not be felt or seen, or that could not be heard as natural sound or as man-made music: no ghosts and no mysteries, except the mystery of human genius. The melody is waiting in the strings of the instrument, and even the inspiration of a poet exists also as an excited physical state, from which the poet’s words and rhythms emerge.

For Diderot, as for Spinoza, Nature is a seamless whole (“le tout“), one all-inclusive system of systems of systems…ad infinitum: nothing supernatural and transcendent can conceivably exist, and we must restore in our own consciousness a sense of acting within the undivided universe, and by this means restore also a sense of personal, mind-body wholeness. Our morality comes from our passions, and not from any authority, and therefore its prescriptions are not in their nature absolute: they need to be modified and adapted to circumstance. Each of the five stories, translated by Mr. Furbank, in ‘This Is Not a Storyand Other Stories is designed to show the uncertainty of many moral prescriptions in actual experience and their dependence upon natural feelings.

As Mr. Furbank emphasizes in his introduction to this translation, the five stories are a mixture of fiction and fact, with a cast of real and imaginary persons, all with a view to confusing the reader and leaving him without a too definite moral message. The theme in all five stories is the ambiguity of morals and the difficulty of distinguishing, in any testing case, virtue and so-called “virtue”—the virtue of priests, prigs, and puritans who, thinking themselves as divided into two parts, higher and lower, reject the multiple promptings of Nature. Mr. Furbank shows how Diderot’s family perfectly illustrated his moral theories: a noble and generous, but strict, father who had his son arrested and imprisoned in a monastery when Denis was contumacious at the time of his marriage; an adoring sister; a brother, l’abbé Diderot, who seems to have been in every way the exact opposite of his brother—intensely pious, moralistic, self-righteous, envious, and humorless.

When in the last two centuries the French Englightenment has been discussed, it has often been accused of reducing all human interests to two basic instincts—the pursuit of pleasure and the avoidance of pain. In the “Reputation of Helvétius” Diderot argues that Helvétius’s reductions are an elementary confusion of preconditions with causes. Characteristically he imagines the “heroic vanity” of those who think of their posthumous fame, and who tremble with joy at “the sweet melody of this distant concert of voices occupied in celebrating them.” Susceptibility to physical sensations is the biological precondition of this heartfelt feeling, but its cause is human thought and reflection, a specifically human cause. We should not look for universal causes in human life: chance and diverse contingent needs determine our lives. “Who should know this better then?” wrote Diderot. “That is the reason why I have spent about thirty years on end, contrary to my taste, on the Encyclopaedia and have only written two plays.”

In a single volume, comfortably held, it is quite impossible to do justice to the superabundance of Diderot’s adventures and friendships and also to his writings, which fill a stout volume in the Pléiade edition even apart from his anonymous contributions to the Encyclopedia. Mr. Furbank has cut a pleasant and central path through the thicket, while also directing the reader’s attention to dense subjects along the path, subjects which he has no space to treat adequately: for instance, the ups and downs of Diderot’s relations with Voltaire and Rousseau, his interests in contemporary biology and his relations with Maupertuis and Buffon, the philosophy of organism, and of systems, which emerged from his studies in biology, his attachment to the ancient world and to the personality of Socrates, the theory of expression which he developed in the Salon, the quality of thought, and the theories of happiness, which appear in his letters to Sophie Volland, that are, as works of literature, almost as memorable as Le Rêve de D’Alembert or Jacques le Fataliste or Le Neveu de Rameau.

But Mr. Furbank does convey an impression of the superabundance of his subject as well as of the enduring charm and gaiety of the man who was not without his darker premonitions. Perhaps Diderot’s charm has stood in the way of his thought, casually sophisticated and unpretentiously profound as it was. There was no one-sidedness, no fanaticism in his thinking, and no Voltairean dryness either. After Diderot came the thunderous emphases and the overweening spirituality of the German Enlightenment and of German Romanticism and its aftermath. Charm was suppressed in philosophy, and tentative dialogues were replaced by grand and solemn monologues, some of them predicting that the world must come to an end with German philosophy. It is delightful to be taken back behind all that by Mr. Furbank, to an unsystematic philosopher, who can almost be heard talking.

This Issue

March 4, 1993