Of that vast intellectual movement which prepared the way for the most stupendous event in history, the French Revolution, Voltaire was the creative spirit.

But there was a group of men, less famous but not less great, who also heralded the coming of the new heaven and the new earth; who were in a strict sense friends and fellow-workers of Voltaire, although one or two of them were personally little known to him; whose aim was his aim, to destroy from among the people ‘ignorance, the curse of God,’ and who were, as he was, the prophets and the makers of a new dispensation.

That many of these light bringers were themselves full of darkness, is true enough; but they brought the light not the less, and in their own breasts burnt one cleansing flame, the passion for humanity.

For the rest, they were the typical men of the most enthralling age in history—each with his human story as well as his public purpose, and his part to play on the glittering stage of the social life of old France, as well as in the great events which moulded her destiny and affected the fate of Europe.

. . . . . .

Foremost among them was d’Alembert.

Often talked about but little known, or vaguely remembered only as the patient lover of Mademoiselle de Lespinasse, Jean Lerond d’Alembert, the successor of Newton, the author of the Preface of the EncyclopÆdia, deserves an enduring fame.

On a November evening in the year 1717, one hundred and eighty-nine years ago, a gendarme, going his round in Paris, discovered on the steps of the church of Saint-Jean Lerond, once the baptistery of Notre-Dame, a child of a few hours old. The story runs that the baby was richly clad, and had on his small person marks which would lead to his identification. But the fact remains that he was abandoned in mid-winter, left without food or shelter to take his feeble chance of life and of the cold charity of some such institution as the Enfants TrouvÉs. It was no thanks to the mother who bore him that the gendarme who found him had compassion on his helpless infancy. The man had the baby hurriedly christened after his first cradle, Jean Baptiste Lerond, took him to a working woman whom he could trust, and who nursed him—for six weeks say some authorities, for a few days say others—in the little village of CrÉmery near Montdidier.

At the end of the time there returned to Paris a certain gallant General Destouches, who had been abroad in the execution of his military duties. He went to visit Madame de Tencin, and from her learnt of the birth and the abandonment of their son.

No study of the eighteenth century can be complete without mention of the extraordinary women who were born with that marvellous age, and fortunately died with it. Cold, calculating, and corrupt, with the devilish cleverness of a Machiavelli, with the natural instinct of love used for gain and for trickery, and with the natural instinct of maternity wholly absent, d’Alembert’s mother was the most perfect type of this monstrous class. Small, keen, alert, with a little sharp face like a bird’s, brilliantly eloquent, bold, subtle, tireless, a great minister of intrigue, and insatiably ambitious—such was Madame de Tencin. It was she who assisted at the meetings of statesmen, and gave Marshal Richelieu a plan and a line of conduct. It was she who managed the affairs of her brother Cardinal de Tencin, and, through him, tried to effect peace between France and Frederick in the midst of the Seven Years’ War. It was she who fought the hideous incompetence of Maurepas, the Naval Minister; and it was she who summed herself up to Fontenelle when she laid her hand on her heart, saying, ‘Here is nothing but brain.’

From the moment of his birth she had only one wish with regard to her child—to be rid of him. A long procession of lovers had left her wholly incapable of shame. But the child would be a worry—and she did not mean to be worried! If the father had better instincts—well, let him follow them. He did. He employed Molin, Madame de Tencin’s doctor, to find out the baby’s nurse, Anne Lemaire, and claim the little creature from her.

The great d’Alembert told Madame Suard many years after how Destouches drove all round Paris with the baby (‘with a head no bigger than an apple’) in his arms, trying to find for him a suitable foster-mother. But little Jean Baptiste Lerond seemed to be dying, and no one would take him. At last, however, Destouches discovered, living in the Rue Michel-Lecomte, a poor glazier’s wife, whose motherly soul was touched by the infant’s piteous plight, and who took him to her love and care, and kept him there for fifty years.

History has concerned itself much less with Madame Rousseau than with Madame de Tencin. Yet it was the glazier’s wife who was d’Alembert’s real mother after all. If she was low-born and ignorant, she had yet the happiest of all acquirements—she knew how to win love and to keep it. The great d’Alembert, universally acclaimed as one of the first intellects of Europe, had ever for this simple person, who defined a philosopher as ‘a fool who torments himself during his life that people may talk of him when he is dead,’ the tender reverence which true greatness, and only true greatness perhaps, can bear towards homely goodness. From her he learnt the blessing of peace and obscurity. From his association with her he learnt his noble idea—difficult in any age, but in that age of degrading luxury and self-indulgence well nigh impossible—that it is sinful to enjoy superfluities while other men want necessaries. His hidden life in the dark attic above her husband’s shop made it possible for him to do that life’s work. For nearly half a century he knew no other home. When he left her roof at last, in obedience to the voice of the most masterful of all human passions, he still retained for her the tenderest affection, and bestowed upon her and her grandchildren the kindness of one of the kindest hearts that ever beautified a great intelligence.

Little Jean Baptiste was put to a school in the Faubourg Saint-Antoine, where he passed as Madame Rousseau’s son. General Destouches paid the expenses of this schooling, took a keen pleasure in the child’s brightness and precocity, and came often to see him. One day he persuaded Madame de Tencin to accompany him. The seven-year-old Jean Baptiste remembered that scene all his life. ‘Confess, Madame,’ says Destouches, when they had listened to the boy’s clever answers to his master’s questions, ‘that it was a pity to abandon such a child.’ Madame rose at once. ‘Let us go. I see it is going to be very uncomfortable for me here.’ She never came again.

Destouches died in 1726, when his son was nine years old. He left the boy twelve hundred livres, and commended him to the care of his relatives. Through them, at the age of twelve, Jean Baptiste received the great favour of being admitted to the College of the Four Nations, founded by Mazarin, and in 1729 the most exclusive school in France. Fortunately for its new scholar it was something besides fashionable, and did its best to satisfy his extraordinary thirst for knowledge. His teachers were all priests and Jansenists, and nourished their apt scholar on Jansenist literature, imbuing him with the fashionable theories of Descartes. How soon was it that they began to hope and dream that in the gentle student called Lerond, living on a narrow pittance above a tradesman’s shop, they had found a new Pascal, a mighty enemy of the Archfiend Jesuitism?

But beneath his timid and modest exterior there lay already an intellect of marvellous strength and clearness, a relentless logic that tested and weighed every principle instilled in him, every theory masquerading as a fact. He quickly became equally hostile to both Jesuit and Jansenist. It was at school that he learnt to hate with an undying hatred, religion—the religion that in forty years launched, on account of the Bull Unigenitus, forty thousand lettres de cachet, that made men forget not only their Christianity but their humanity, and give themselves over body and soul to the devouring fever called fanaticism. At school also he conceived his passion for mathematics, that love of exact truth which no Jansenist priest, however subtle, could make him regard as a dangerous error.

When he was eighteen, in 1735, he took his degree of Bachelor of Arts and changed his name. D’Alembert is thought to be an anagram on Baptiste Lerond. Anagrams were fashionable, and one Arouet, who had elected to be called Voltaire, had made such an alteration of good omen. D’Alembert went on studying at the College, but throughout his studies mathematics were wooing him from all other pursuits. The taste, however, was so unlucrative, and the income from twelve hundred livres so small, that a profession became a necessity. The young man conscientiously qualified for a barrister. But ‘he loved only good causes’ and was naturally shy. He never appeared at the Bar.

Then he bethought him of medicine. He would be a doctor! But again and again the siren voice of his dominant taste called him back to her. His friends—those omniscient friends always ready to put a spoke in the wheel of genius—entreated him to be practical, to remember his poverty, and to make haste to grow rich. He yielded to them so far that one day he carried all his geometrical books to one of their houses, and went back to the garret at Madame Rousseau’s to study medicine and nothing else in the world. But the geometrical problems disturbed his sleep.

Fate wanted d’Alembert, the great mathematician, not some prosperous, unproductive mediocrity of a Paris apothecary. The crowning blessing of life, to be born with a bias to some pursuit, was this man’s to the full.

He yielded to Nature and to God. He brought back the books he had abandoned, flung aside those for which he had neither taste nor aptitude, and at twenty gave himself to the work for which he had been created.

Some artist should put on canvas the picture of this student, sitting in his ill-aired garret with its narrow prospect of ‘three ells of sky,’ poor, delicate, obscure—or rich, rather, in the purest of earthly enjoyments, the pursuit of truth for its own sake. He could not afford to buy many of the books he needed, so he borrowed them from public libraries. He left the work of the day anticipating with joy the work of the morrow. For the world he cared nothing, and of him it knew nothing. Fame?—he did not want it. Wealth?—he could do without it. Poor as he was, there was no time when he even thought of taking pupils, or using the leisure he needed for study in making money by a professorship.

To give knowledge was his work and his aim; to make knowledge easier for others he left to some lesser man. His style had seldom the grace and clearness which can make, and which in many of his fellow-workers did make, the abstrusest reasoning charm like romance. D’Alembert left Diderot to put his thought into irresistible words, and Voltaire and Turgot to translate it into immortal deeds.

When he was two-and-twenty, in 1739, d’Alembert began his connection with the Academy of Sciences. In 1743 he published his ‘Treatise on Dynamics.’ Now little read and long superseded, it placed him at one bound, and at six-and-twenty years old, among the first geometricians of Europe. Modest, frugal, retiring as he was and remained, he was no more only the loving and patient disciple of science. He was its master and teacher. In 1746 his ‘Treatise on the Theory of Winds’ gained him a prize in the Academy of Berlin, and first brought him into relationship with Frederick the Great.

Two years later, when her son was of daily growing renown, Madame de Tencin died. The story that, when he had become famous and she would fain have acknowledged him, he had repudiated her, saying he had no mother but the glazier’s wife, d’Alembert, declares Madame Suard, always denied. ‘I should never have refused her endearments—it would have been too sweet to me to recover her.’ That answer is more in keeping with a temperament but too gentle and forgiving, than the spirited repulse. It was in keeping also with the life of Madame de Tencin that even death should leave her indifferent to her child. She thought no more of him, he said, in the one than in the other. Her money she left to her doctor.

If the studious poverty of the life in the glazier’s attic spared d’Alembert acquaintances, it did not deprive him of friends.

Then living in Paris, some six-and-thirty years old, the author of the ‘Philosophical Thoughts,’ and the most fascinating scoundrel in France, was Denis Diderot. With the quiet d’Alembert, of morals almost austere and of hidden, frugal life, what could a Diderot have in common? Something more than the attraction of opposites drew them together. The vehement and all-embracing imagination of the one fired the calm reason of the other. The hot head and the cool one were laid together, and the result was the great EncyclopÆdia.

The first idea of the pair was modest enough—to translate into French the English EncyclopÆdia of Chambers. But had not brother Voltaire said that no man who could make an adequate translation ever wasted his time in translating? They soon out-ran so timid an ambition. The thing must not only be spontaneous work; it must wholly surpass all its patterns and prototypes. It must be not an EncyclopÆdia, but the EncyclopÆdia. Every man of talent in France must bring a stone towards the building of the great Temple. From Switzerland, old Voltaire shall pour forth inspiration, encouragement, incentive. Rousseau shall lend it the glow of his passion, and Grimm his journalistic versatility. HelvÉtius shall contribute—d’Holbach, Turgot, Morellet, Marmontel, Raynal, La Harpe, de Jaucourt, Duclos.

And the Preliminary Discourse shall be the work of d’Alembert.

An envious enemy once dismissed him scornfully as

Yet if he had written nothing but that Preface he would still have had noble titles to fame. It contained, as he himself said, the quintessence of twenty years’ study. If his style was usually cold and formal, it was not so now. With warmest eloquence and boldest brush he painted the picture of the progress of the human mind since the invention of printing. From the lofty heights man’s intellect had scaled there stood out yet mightier heights for him to dare! Advance! advance! If ever preface said anything, the Preface to the great EncyclopÆdia says this. Clothed with light and fire, that dearest son of d’Alembert’s genius went forth to illuminate and to astound the world.

At first the EncyclopÆdia was not only heard gladly by the common people, but was splendidly set forth with the approbation and PrivilÈge du Roi. Even the wise and thoughtful melancholy of d’Alembert’s temperament may have been cheered by such good fortune, while the sanguine Diderot naturally felt convinced it would last for ever.

Both worked unremittingly. His authorship of the Preface immediately flung open to d’Alembert all the salons in Paris, and for the first time in his life he began to go into society. Then Frederick the Great made him a rich and splendid offer, the Presidency of the Berlin Academy. Consider that though the man was famous he was still very poor. The little pension which was his all ‘is hardly enough to keep me if I have the happiness or the misfortune to live to be old.’ From the Government of his country he feared everything and hoped nothing. He was only thirty-five years of age. A new world was opened to him. The glazier’s attic he could exchange for a palace, and the homely kindness of an illiterate foster-mother for the magnificent endearments of a philosophic king. Was it only the painful example of friend Voltaire’s angry wretchedness as Frederick’s guest that made him refuse an offer so lavish and so dazzling? It was rather that he had the rare wisdom to recognise happiness when he had it and did not mistake it for some phantom will-o’-the-wisp whom distance clothed with light. ‘The peace I enjoy is so perfect,’ he wrote, ‘I dare run no risk of disturbing it.... I do not doubt the King’s goodness ... only that the conditions essential to happiness are not in his power.’

Any man who is offered in place of quiet content that most fleeting and unsubstantial of all chimeras—fame and glory—should read d’Alembert’s answer to Frederick the Great.

Frederick’s royal response to it was the offer of a pension of twelve hundred livres.

In September 1754 the fourth volume of the EncyclopÆdia was hailed by the world with a burst of enthusiasm and applause, and in the December of that year d’Alembert received as a reward for his indefatigable labours a chair in the French Academy. He had only accepted it on condition that he spoke his mind freely on all points and made court to no man. The speech with which he took his seat, though constantly interrupted with clapping and cries of delight, was not good, said Grimm. All d’Alembert’s addresses and Éloges spoken at the Academy leave posterity, indeed, as cold as they left the astute German journalist. The man was a mathematician, a creature of reason. The passion that was to rule that reason and dominate his life was not the gaudy and shallow passion of the orator.

In 1756 he went to stay with the great head of his party, Voltaire, at the DÉlices, near Geneva. The Patriarch was sixty-two years old, but with the activity and the enthusiasm of youth. At his house and at his table d’Alembert met constantly and observed deeply the Calvinistic pastors of Geneva. He returned to Paris with his head full of the most famous article the EncyclopÆdia was to know. At the back of his mind was a certain request of his host’s, that he should also make a few remarks on the benefits that play-acting would confer on the Calvinistic temperament.

No article in that ‘huge folio dictionary’ brewed so fierce a storm or had consequences so memorable and far-reaching as d’Alembert’s article ‘Geneva.’ In his reserved and formal style he punctiliously complimented the descendants of Calvin as preferring reason to faith, sound sense to dogma, and as having a religion which, weighed and tested, was nothing but a perfect Socinianism. Voltaire laughed long in his sleeve, and in private executed moral capers of delight. The few words on the advantages of play-acting, which he had begged might be added, had not been forgotten.

The Genevan pastors took solemn and heartburning counsel together, and on the head of the quiet worker in the attic in Paris there burst a hurricane which might have beaten down coarser natures and frightened stouter hearts. Calvinism fell upon him, whose sole crime had been to show her the logical outcome of her doctrines, with the fierce fury of a desperate cause. Retract! retract! or at least give the names of those of our pastors who made you believe in the rationalism of our creed! As for the remarks on plays, why, Jean Jacques Rousseau, our citizen and your brother philosopher, shall answer those, and in the dazzling rhetoric of the immortal ‘Letter on Plays’ give, with all the magic and enchantment of his sophist’s genius, the case against the theatre.

Then, on March 8, 1759, the paternal government of France, joining hands with Geneva, suppressed by royal edict that EncyclopÆdia of which a very few years earlier it had solemnly approved. The accursed thing was burnt by the hangman. The printers and publishers were sent to the galleys or to death. The permit to continue publishing the work was rescinded. The full flowing fountain of knowledge was dammed, and the self-denial of d’Alembert’s patient life wasted. The gentle heart, which had never harmed living creature, fell stricken beneath the torrent of filthy fury which the gutter press poured upon him. His Majesty—his besotted Majesty, King Louis the Fifteenth—finds in the EncyclopÆdia, forsooth, ‘maxims tending to destroy Royal authority and to establish independence ... corruption of morals, irreligion, and unbelief.’ Sycophant and toadying Paris went with him. Furious and blaspheming, passionate Diderot came out to meet the foe. Dancing with rage, old Voltaire at DÉlices could only calm himself enough to hold a pen in his shaking fingers and pour out incentives to his brothers in Paris to fight till the death. To him injustice was ever the bugle-call to battle. But not to d’Alembert. He shrank back into his shell, dumb and wounded. ‘I do not know if the EncyclopÆdia will be continued,’ he wrote, ‘but I am sure it will not be continued by me.’ Even the stirring incitements of his chief could not alter his purpose. He had offered sight to the blind, and they had chosen darkness; he would bring them the light no more. That Diderot considered him traitor and apostate did not move him. He would not quarrel with that affectionate, hot-headed brother worker, but for himself that chapter of his life was finished, and he turned the page.

In the very same year he gave to a thankless world his ‘Elements of Philosophy;’ and he again refused Frederick the Great’s invitation to exchange persecuting Paris for the Presidency of the Berlin Academy. But there was no reason why he should not escape from his troubles for a time and become Frederick’s visitor.

In 1762 he went to Berlin for two months, and found the great King a clever, generous, and devoted friend. But though he continued to beg d’Alembert to stay with him permanently, and was lavish of gifts and promises, the wise and judicious visitor was wholly proof against the royal blandishments. In the same year he refused a yet more dazzling offer—to be tutor to Catherine the Great’s son. He had already in Paris, not only ties, which might be broken, but a tie, which he found indissoluble.

In 1765, three years after Catherine’s offer had been made and declined, d’Alembert, when he was forty-eight years old, was attacked by a severe illness, which, said his accommodating doctor, required larger and airier rooms than those in his good old nurse’s home. He was moved from the familiar Rue Michel-Lecomte to the Boulevard du Temple. There Mademoiselle de Lespinasse joined him and nursed him back to health.

In all the story of d’Alembert’s life, in that age of unbridled licence, no woman’s name is connected with his save this one’s. Fifteen years earlier he had made the acquaintance of Madame du Deffand. To the blind old worldling, who loved Horace Walpole and wrote immortal letters, he stood in the nature of a dear and promising son. For many years he was always about her house. His wit and his charm, seasoned by a gentle spice of irony and a delightful talent for telling stories and enjoying them himself, naturally endeared him to the old woman whose one hell was boredom. On his side, he came because he liked her, and stayed because he loved Mademoiselle de Lespinasse. The history of that mÉnage of the brilliant, impulsive, undisciplined girl, with her plain face and her matchless charm, and of the blind old woman she tended, deceived, and outwitted, has been told in fiction as well as in history. How when Madame du Deffand was asleep, her poor companion held for herself reunions of the bright, particular stars of her mistress’s firmament, and how the old woman, rising a little too early one day, came into the room and with her sightless eyes saw all, is one of the familiar anecdotes of literature.

Long before this dramatic dÉnouement, d’Alembert and Julie de Lespinasse had been something more than friends. But now Mademoiselle saw herself cast adrift on the world. She flung to it her reputation, and yielded, not so much to the entreaties of d’Alembert’s love, as to the more pitiful pleading his solitude and sickness made to the warm maternity in her woman’s heart. She nursed him back to convalescence, and then lived beneath the same roof with him in the Rue Belle Chasse.

Picture the man with his wide, wise intelligence and his diffident and gentle nature, and the woman with her brilliant intuition and her quick, glowing impulse. To his exact logic she could add feeling, passion, sympathy; his frigid and awkward style she could endow with life and fire. Many of his manuscripts are covered with her handwriting. Some, she certainly inspired. She had read widely and felt keenly, and her lover had weighed, pondered, considered. For him, who had for himself no ambition, she could dare and hope all. The perpetual Secretaryship of the Academy shall be turned from a dream to a fact! In that age of women’s influence no woman had in her frail hands more to give and to withhold than this poor companion, whose marvellous power over men and destinies lay not in her head, but in her heart. The true complement of a d’Alembert, daring where he was timid, fervent where he was cold, a woman’s feeling to quicken his man’s reason—here should have been indeed the marriage of true minds.

Yet d’Alembert’s is the most piteous love-story in history. If Mademoiselle had yielded to his sadness and his loneliness, she had never loved him. Only a year after she had joined him, d’Alembert, alluding to some rumours which had been afloat concerning their marriage, wrote bitterly, ‘What should I do with a wife and children?’ But there was only one real obstacle to their union. Across Mademoiselle’s undisciplined heart there lay already the shadows of another passion.

From the first the household in the Rue Belle Chasse had been absolutely dominated by the woman. ‘In love, who loves least, rules.’ D’Alembert was in bondage while she was free. To keep her, he submitted to humours full of bitterness and sharpness—the caprices of that indifferent affection which gives nothing and exacts all. In her hands, he was as a child; his philosophies went to the winds; his very reason was prostrate. How soon was it he began to guess he had a rival in her heart?

It was not till after her death that he found out for certain that less than two years after she came to him she had given herself, body and soul, to the young Marquis de Mora. But what he did not know, he must have greatly suspected. It was he who wrote her letters and ran her errands. Grimm recorded in the ‘Literary Correspondence’ the prodigious ascendency she had acquired over all his thoughts and actions. ‘No luckless Savoyard of Paris ... does so many wearisome commissions as the first geometrician of Europe, the chief of the EncyclopÆdic sect, the dictator of our Academies, does for Mademoiselle.’ He would post her fervent outpourings to the man who had supplanted him, and call for the replies at the post-office that she might receive them an hour or two earlier. What wonder that over such a character, a nature like Mademoiselle’s rode roughshod, that she hurt and bruised him a hundred times a day, and wounded while she despised him? No woman ever truly loves a man who does not exact from her not only complete fidelity to himself, but fidelity to all that is best and highest in her own nature.

D’Alembert had indeed in full measure the virtue of his defects. If it was a crime to be tender to her sins, it was nobility to be gentle to her sufferings. He bore and forbore with her endlessly. Always patient and good-humoured, thinking greatly of her and little of himself, abundant in compassion for her ruined nerves and the querulous feverishness of her ill health—here surely were some of the noble traits of a good love. He read to her, watched by her, tended her, and in the matchless society they gathered round them was abundantly content to be nothing, that she might be all.

Their life together in the Rue Belle Chasse had not in the least shocked their easy-going world. Many persons comfortably maintained that their association was the merest friendship—heedless of that amply proven fact that where people avoid evil, they avoid also the appearance of evil. The eighteenth century, indeed, even if it saw any difference between vice and virtue, which is doubtful, did not in the least mind if its favourites were vicious or virtuous, provided they were not dull. D’Alembert and Mademoiselle de Lespinasse did not fall under that ban. The hermit life the man had led was over for ever. In her modest room in that dingy street, Mademoiselle held every night the most famous salon in Paris.

Most of the salons may be exhaustively described as having been nourished on a little eau sucrÉ and a great deal of wit. But to this one wit alone was light, food, and air. Mademoiselle did not require to give dinners like Madame Necker, or suppers like Madame du Deffand; neither for the beauty which, later, was to make men forgive the mental limitations of Madame RÉcamier, had she need or use. Tall, pale, and slender, with her infinite, unconscious tact, her mental grace, and her divine sympathy, her passage through the social life of her age has left the subtle perfume of some delicate flower. To be her friend was to feel complete, understood, satisfied. To her, as to a sister of consolation, came Condorcet, marquis, mathematician, philosopher; Saint-Pierre, the pupil of Rousseau and the creator of ‘Paul and Virginia;’ La Harpe, whom she was to help to the Academy; HÉnault, whom she had charmed from Madame du Deffand; Turgot, Chastellux, Marmontel. And quietly effacing himself, with that true greatness which is never afraid to be made of little account, was Mademoiselle’s lover and the noblest intellect of them all, d’Alembert.

There is no more delightful trait in his character than this exquisite talent for modesty. With his spare form always dressed from head to foot in clothes of one colour, the aim of d’Alembert was both physically and mentally, as it were, to escape notice. True, when he talked, the listener must needs marvel at the breadth, the variety, the exhaustless interests of the mind, and its perfect simplicity and straightforwardness. But he did not want to talk much. He liked better to listen. He preferred in society, as he preferred in life, to think while other men said and did.

No social pleasures could either supersede the work of his life, or make compensation for the sorrows of his soul. He had already thrown in his lot with Mademoiselle when he published the most daring of all his books, ‘The History of the Destruction of the Jesuits.’ Her treachery had shattered his life for five years, when he asked Frederick the Great for a sum of money which would enable him to travel and heal his broken health and heart. In 1770, with young Condorcet for his companion, he left Paris for Italy, stopped at Ferney, and spent his whole leave of absence with Voltaire.

It was an oasis in the desert of the feverish existence to which he had condemned himself. In mighty speculation, in splendid visions of the future of the race, in passionate argument on the immortality of the soul and the being and nature of God, he forgot his personal sorrows. The mind dominated and the heart was still. What nights the three must have spent together—Voltaire with his octogenarian’s intellect as keen and bright as a boy’s, the young Marquis, sharp-set to learn, and d’Alembert with his ‘just mind and inexhaustible imagination’—when they could get rid of that babbling inconsequence, Voltaire’s niece, Madame Denis, and sit hour after hour discussing, planning, dreaming! The quiet d’Alembert went, as quiet people often do, far beyond his impulsive and outspoken companions in speculative daring. Though there is not an anti-Christian line in any of his published writings except his correspondence, yet the scepticism of this gentle mathematician far exceeded that of him who is accounted the Prince of Unbelievers, and where his host was a hotly convinced Deist, d’Alembert only thought the probabilities in favour of Theism, and was far more Voltairian than Voltaire. It was the old Pontiff of the Church of Anti-Christ who stopped a conversation at his table wherein d’Alembert had spoken of the very existence of God as a moot point, by sending the servants out of the room, and then turning to his guests with—‘And now, gentlemen, continue your attack upon God. But as I do not want to be murdered or robbed to-night by my servants, they had better not hear you.’

The visit lasted in all two months. D’Alembert abandoned the Italian journey, offered King Frederick his change, and returned to Paris.

In 1772 he was made Perpetual Secretary of the French Academy. He, whose needs, said Grimm, were always the measure of his ambitions, had scaled heights, not beyond his deserts, but beyond his wishes. He was also a member of the scientific Academies of Prussia, Russia, Portugal, Naples, Turin, Norway, Padua, and of the literary academies of Sweden and Bologna. But if ‘the end of all ambition is to be happy at home,’ d’Alembert had failed. When the Perpetual Secretaryship was still a new and dazzling possession, the Perpetual Secretary found at home the woman to whom he was captive soul and body, in the throes of another passion. False to de Mora, as she had been false to him, she was then writing to de Guibert those love-letters which have given her a place beside Sappho and EloÏsa and have added a classic to literature. It was d’Alembert’s part to listen to self-reproaches whose justice he might well guess, to look into the depths of a tenderness in which he had no share. Once he gave her his portrait with these lines beneath it:

She herself said that of all the feelings she had inspired, his alone had not brought her wretchedness.

In 1775 de Guibert was married. The marriage was Mademoiselle’s death-blow. The fever of the soul became a disease of the body. Sometimes bitterly repentant and sometimes only captious and difficult; now, her true self full of tenderness and charm: and now, reckless, selfish, despairing—d’Alembert’s patience and goodness were inexhaustible. True to his character, he stood aside that to the last her friends might visit her, that to the last she might help and feel for them.

But though the spirit still triumphed at moments over the body, the end was near. When her misery was dulled by opium, d’Alembert was always watching, unheeded, at her bedside. It was the attitude of his life. When she became conscious, he was there still. Before she died, she asked his pardon; but de Guibert’s was the last name upon her lips. She died on May 23, 1776, not yet forty-five years old.

D’Alembert’s grief seems to have taken by surprise many short-sighted friends who had supposed that quiet exterior to hide a cold, or an unawakened, heart. He was utterly crushed and broken. His life had lost at once its inspiration and its meaning. For the sake of Mademoiselle he had grown old without family and without hope. His friends, in that age of noble friendships, did their best to comfort him. But his wounds were deeper than they knew. With a super-refinement of selfishness or cruelty, Mademoiselle had left him her Correspondence. She had not preserved in it one single line of the many letters he had himself written to her, while it contained full and certain proofs of her double infidelity.

He who has lost only those of whose faith and truth he is sure, has not yet reached the depth of human desolation.

After a while, d’Alembert tried to return to his first affection—that cold but faithful mistress, his mathematical studies. At the Academy he pronounced the Éloge of Louis de Sacy, who had been the lover of the Marquise de Lambert. For the first time he looked into his heart and wrote, and thus for the first time he touched the hearts of others; the cold style took fire, and beneath the clumsy periods welled tears.

But the writer was consumed to the soul with grief and weariness. This was not the man who could use sorrow as a spur to new endeavour and to nobler work. Before the persecutions which had assailed the EncyclopÆdia he had bowed his head and taken covert, and the death of his mistress broke not only his heart, but his spirit and his life. From Madame Marmontel and from Thomas, he derived, it is said, some sort of comfort: Condorcet was as a son; but with Mademoiselle’s death the light of her society had gone out. The friends who remained were but pale stars in a dark sky. D’Alembert was growing old. He suffered from a cruel disease and could not face the horrors of the operation which might have relieved it. ‘Those are fortunate who have courage,’ said he; ‘for myself, I have none.’ It was life, not death, he dreaded. What use then to suffer only to prolong suffering?

The mental enlightenment he had given the world, the wider knowledge which he had lived to impart, consoled this dying thinker scarcely at all. He was to his last hour what he had been when Mademoiselle took ill-fated compassion on his dependence and loneliness—a child, affectionate, solitary, tractable, with the great mind always weighed down by the supersensitiveness of a child’s heart and with a child’s clinging need of care and tenderness. He died on October 29, 1783.

The man whose only reason for dreading poverty had been lest he should be forced to reduce his charities, left, as might have been expected, a very small fortune. Condorcet was his residuary legatee, and made his Éloge in both the Academies.

Diderot himself was dying when he heard of his old friend’s death. ‘A great light has gone out,’ said he. Euler, d’Alembert’s brother, and sometimes his rival, geometrician, survived him only a few months. And Voltaire, the quick and life-giving spirit of the vast movement of which d’Alembert was the Logic, the Reason, the Thought, had already died to earth, though he lived to everlasting fame.

D’Alembert owes his greatest reputation to geometry. But, as Grimm said, in that department only geometricians can exactly render him his due: ‘He added to the discoveries of the Eulers ... and the Newtons.’ To the general public his great title to glory lies in the mighty help he gave to that great monument of Voltairian philosophy, the EncyclopÆdia. The Preface was ‘a work for which he had no model.’ By it, he introduced to the world that book which Diderot produced, and which, except the Bible and the Koran, may be justly said to have been the most influential book in history; which gave France, and, through France, Europe, that new light and knowledge which brought with them a nobler civilisation and a recognition of the universal rights of man.

In himself, d’Alembert was always rather a great intelligence than a great character. To the magnificence of the one he owed all that has made him immortal, and to the weakness of the other the sorrows and the failures of his life. For it is by character and not by intellect the world is won.