And the beams were decidedly refulgent—so much so, in fact, that they almost satisfied even the vanity of Voltaire. Almost, but not quite. For, though his glory was great, though he was the centre of all men's admiration, courted by nobles, flattered by princesses—there is a letter from one of them, a sister of Frederick's, still extant, wherein the trembling votaress ventures to praise the great man's works, which, she says, 'vous rendent si célèbre et immortel'—though he had ample leisure for his private activities, though he enjoyed every day the brilliant conversation of the King, though he could often forget for weeks together that he was the paid servant of a jealous despot—yet, in spite of all, there was a crumpled rose-leaf amid the silken sheets, and he lay awake o' nights. He was not the only Frenchman at Frederick's court. That monarch had surrounded himself with a small group of persons—foreigners for the most part—whose business it was to instruct him when he wished to improve his mind, to flatter him when he was out of temper, and to entertain him when he was bored. There was hardly one of them that was not thoroughly second-rate. Algarotti was an elegant dabbler in scientific matters—he had written a book to explain Newton to the ladies; d'Argens was an amiable and erudite writer of a dull free-thinking turn; Chasot was a retired military man with too many debts, and Darget was a good-natured secretary with too many love affairs; La Mettrie was a doctor who had been exiled from France for atheism and bad manners; and Pöllnitz was a decaying baron who, under stress of circumstances, had unfortunately been obliged to change his religion six times.
These were the boon companions among whom Frederick chose to spend his leisure hours. Whenever he had nothing better to do, he would exchange rhymed epigrams with Algarotti, or discuss the Jewish religion with d'Argens, or write long improper poems about Darget, in the style of La Pucelle. Or else he would summon La Mettrie, who would forthwith prove the irrefutability of materialism in a series of wild paradoxes, shout with laughter, suddenly shudder and cross himself on upsetting the salt, and eventually pursue his majesty with his buffooneries into a place where even royal persons are wont to be left alone. At other times Frederick would amuse himself by first cutting down the pension of Pöllnitz, who was at the moment a Lutheran, and then writing long and serious letters to him suggesting that if he would only become a Catholic again he might be made a Silesian Abbot. Strangely enough, Frederick was not popular, and one or other of the inmates of his little menagerie was constantly escaping and running away. Darget and Chasot both succeeded in getting through the wires; they obtained leave to visit Paris, and stayed there. Poor d'Argens often tried to follow their example; more than once he set off for France, secretly vowing never to return; but he had no money, Frederick was blandishing, and the wretch was always lured back to captivity. As for La Mettrie, he made his escape in a different manner—by dying after supper one evening of a surfeit of pheasant pie. 'Jésus! Marie!' he gasped, as he felt the pains of death upon him. 'Ah!' said a priest who had been sent for, 'vous voilà enfin retourné à ces noms consolateurs.' La Mettrie, with an oath, expired; and Frederick, on hearing of this unorthodox conclusion, remarked, 'J'en suis bien aise, pour le repos de son âme.'
Among this circle of down-at-heel eccentrics there was a single figure whose distinction and respectability stood out in striking contrast from the rest—that of Maupertuis, who had been, since 1745, the President of the Academy of Sciences at Berlin. Maupertuis has had an unfortunate fate: he was first annihilated by the ridicule of Voltaire, and then recreated by the humour of Carlyle; but he was an ambitious man, very anxious to be famous, and his desire has been gratified in over-flowing measure. During his life he was chiefly known for his voyage to Lapland, and his observations there, by which he was able to substantiate the Newtonian doctrine of the flatness of the earth at the poles. He possessed considerable scientific attainments, he was honest, he was energetic; he appeared to be just the man to revive the waning glories of Prussian science; and when Frederick succeeded in inducing him to come to Berlin as President of his Academy the choice seemed amply justified. Maupertuis had, moreover, some pretensions to wit; and in his earlier days his biting and elegant sarcasms had more than once overwhelmed his scientific adversaries. Such accomplishments suited Frederick admirably. Maupertuis, he declared, was an homme d'esprit, and the happy President became a constant guest at the royal supper-parties. It was the happy—the too happy—President who was the rose-leaf in the bed of Voltaire. The two men had known each other slightly for many years, and had always expressed the highest admiration for each other; but their mutual amiability was now to be put to a severe test. The sagacious Buffon observed the danger from afar: 'ces deux hommes,' he wrote to a friend, 'ne sont pas faits pour demeurer ensemble dans la même chambre.' And indeed to the vain and sensitive poet, uncertain of Frederick's cordiality, suspicious of hidden enemies, intensely jealous of possible rivals, the spectacle of Maupertuis at supper, radiant, at his ease, obviously protected, obviously superior to the shady mediocrities who sat around—that sight was gall and wormwood; and he looked closer, with a new malignity; and then those piercing eyes began to make discoveries, and that relentless brain began to do its work.
Maupertuis had very little judgment; so far from attempting to conciliate Voltaire, he was rash enough to provoke hostilities. It was very natural that he should have lost his temper. He had been for five years the dominating figure in the royal circle, and now suddenly he was deprived of his pre-eminence and thrown completely into the shade. Who could attend to Maupertuis while Voltaire was talking?—Voltaire, who as obviously outshone Maupertuis as Maupertuis outshone La Mettrie and Darget and the rest. In his exasperation the President went to the length of openly giving his protection to a disreputable literary man, La Beaumelle, who was a declared enemy of Voltaire. This meant war, and war was not long in coming.
Some years previously Maupertuis had, as he believed, discovered an important mathematical law—the 'principle of least action.' The law was, in fact, important, and has had a fruitful history in the development of mechanical theory; but, as Mr. Jourdain has shown in a recent monograph, Maupertuis enunciated it incorrectly without realising its true import, and a far more accurate and scientific statement of it was given, within a few months, by Euler. Maupertuis, however, was very proud of his discovery, which, he considered, embodied one of the principal reasons for believing in the existence of God; and he was therefore exceedingly angry when, shortly after Voltaire's arrival in Berlin, a Swiss mathematician, Koenig, published a polite memoir attacking both its accuracy and its originality, and quoted in support of his contention an unpublished letter by Leibnitz, in which the law was more exactly expressed. Instead of arguing upon the merits of the case, Maupertuis declared that the letter of Leibnitz was a forgery, and that therefore Koenig's remarks deserved no further consideration. When Koenig expostulated, Maupertuis decided upon a more drastic step. He summoned a meeting of the Berlin Academy of Sciences, of which Koenig was a member, laid the case before it, and moved that it should solemnly pronounce Koenig a forger, and the letter of Leibnitz supposititious and false. The members of the Academy were frightened; their pensions depended upon the President's good will; and even the illustrious Euler was not ashamed to take part in this absurd and disgraceful condemnation.
Voltaire saw at once that his opportunity had come. Maupertuis had put himself utterly and irretrievably in the wrong. He was wrong in attributing to his discovery a value which it did not possess; he was wrong in denying the authenticity of the Leibnitz letter; above all he was wrong in treating a purely scientific question as the proper subject for the disciplinary jurisdiction of an Academy. If Voltaire struck now, he would have his enemy on the hip. There was only one consideration to give him pause, and that was a grave one: to attack Maupertuis upon this matter was, in effect, to attack the King. Not only was Frederick certainly privy to Maupertuis' action, but he was extremely sensitive of the reputation of his Academy and of its President, and he would certainly consider any interference on the part of Voltaire, who himself drew his wages from the royal purse, as a flagrant act of disloyalty. But Voltaire decided to take the risk. He had now been more than two years in Berlin, and the atmosphere of a Court was beginning to weigh upon his spirit; he was restless, he was reckless, he was spoiling for a fight; he would take on Maupertuis singly or Maupertuis and Frederick combined—he did not much care which, and in any case he flattered himself that he would settle the hash of the President.
As a preparatory measure, he withdrew all his spare cash from Berlin, and invested it with the Duke of Wurtemberg. 'Je mets tout doucement ordre à mes affaires,' he told Madame Denis. Then, on September 18, 1752, there appeared in the papers a short article entitled 'Réponse d'un Académicien de Berlin à un Académicien de Paris.' It was a statement, deadly in its bald simplicity, its studied coldness, its concentrated force, of Koenig's case against Maupertuis. The President must have turned pale as he read it; but the King turned crimson. The terrible indictment could, of course only have been written by one man, and that man was receiving a royal pension of £800 a year and carrying about a Chamberlain's gold key in his pocket. Frederick flew to his writing-table, and composed an indignant pamphlet which he caused to be published with the Prussian arms on the title-page. It was a feeble work, full of exaggerated praises of Maupertuis, and of clumsy invectives against Voltaire: the President's reputation was gravely compared to that of Homer; the author of the 'Réponse d'un Académicien de Berlin' was declared to be a 'faiseur de libelles sans génie,' an 'imposteur effronté,' a 'malheureux écrivain' while the 'Réponse' itself was a 'grossièreté plate,' whose publication was an 'action malicieuse, lâche, infâme,' a 'brigandage affreux.' The presence of the royal insignia only intensified the futility of the outburst. 'L'aigle, le sceptre, et la couronne,' wrote Voltaire to Madame Denis, 'sont bien étonnés de se trouver là.' But one thing was now certain: the King had joined the fray. Voltaire's blood was up, and he was not sorry. A kind of exaltation seized him; from this moment his course was clear—he would do as much damage as he could, and then leave Prussia for ever. And it so happened that just then an unexpected opportunity occurred for one of those furious onslaughts so dear to his heart, with that weapon which he knew so well how to wield. 'Je n'ai point de sceptre,' he ominously shot out to Madame Denis, 'mais j'ai une plume.'
Meanwhile the life of the Court—which passed for the most part at Potsdam, in the little palace of Sans Souci which Frederick had built for himself—proceeded on its accustomed course. It was a singular life, half military, half monastic, rigid, retired, from which all the ordinary pleasures of society were strictly excluded. 'What do you do here?' one of the royal princes was once asked. 'We conjugate the verb s'ennuyer,' was the reply. But, wherever he might be, that was a verb unknown to Voltaire. Shut up all day in the strange little room, still preserved for the eyes of the curious, with its windows opening on the formal garden, and its yellow walls thickly embossed with the brightly coloured shapes of fruits, flowers, birds, and apes, the indefatigable old man worked away at his histories, his tragedies, his Pucelle, and his enormous correspondence. He was, of course, ill—very ill; he was probably, in fact, upon the brink of death; but he had grown accustomed to that situation; and the worse he grew the more furiously he worked. He was a victim, he declared, of erysipelas, dysentery, and scurvy; he was constantly attacked by fever, and all his teeth had fallen out. But he continued to work. On one occasion a friend visited him, and found him in bed. 'J'ai quatre maladies mortelles,' he wailed. 'Pourtant,' remarked the friend, 'vous avez l'oeil fort bon.' Voltaire leapt up from the pillows: 'Ne savez-vous pas,' he shouted, 'que les scorbutiques meurent l'oeil enflammé?' When the evening came it was time to dress, and, in all the pomp of flowing wig and diamond order, to proceed to the little music-room, where his Majesty, after the business of the day, was preparing to relax himself upon the flute. The orchestra was gathered together; the audience was seated; the concerto began. And then the sounds of beauty flowed and trembled, and seemed, for a little space, to triumph over the pains of living and the hard hearts of men; and the royal master poured out his skill in some long and elaborate cadenza, and the adagio came, the marvellous adagio, and the conqueror of Rossbach drew tears from the author of Candide. But a moment later it was supper-time; and the night ended in the oval dining-room, amid laughter and champagne, the ejaculations of La Mettrie, the epigrams of Maupertuis, the sarcasms of Frederick, and the devastating coruscations of Voltaire.
Yet, in spite of all the jests and roses, everyone could hear the rumbling of the volcano under the ground. Everyone could hear, but nobody would listen; the little flames leapt up through the surface, but still the gay life went on; and then the irruption came. Voltaire's enemy had written a book. In the intervals of his more serious labours, the President had put together a series of 'Letters,' in which a number of miscellaneous scientific subjects were treated in a mildly speculative and popular style. The volume was rather dull, and very unimportant; but it happened to appear at this particular moment, and Voltaire pounced upon it with the swift swoop of a hawk on a mouse. The famous Diatribe du Docteur Akakia is still fresh with a fiendish gaiety after a hundred and fifty years; but to realise to the full the skill and malice which went to the making of it, one must at least have glanced at the flat insipid production which called it forth, and noted with what a diabolical art the latent absurdities in poor Maupertuis' rêveries have been detected, dragged forth into the light of day, and nailed to the pillory of an immortal ridicule. The Diatribe, however, is not all mere laughter; there is a real criticism in it, too. For instance, it was not simply a farcical exaggeration to say that Maupertuis had set out to prove the existence of God by 'A plus B divided by Z'; in substance, the charge was both important and well founded. 'Lorsque la métaphysique entre dans la géometrie,' Voltaire wrote in a private letter some months afterwards, 'c'est Arimane qui entre dans le royaume d'Oromasde, et qui y apporte des ténèbres'; and Maupertuis had in fact vitiated his treatment of the 'principle of least action' by his metaphysical pre-occupations. Indeed, all through Voltaire's pamphlet, there is an implied appeal to true scientific principles, an underlying assertion of the paramount importance of the experimental method, a consistent attack upon a priori reasoning, loose statement, and vague conjecture. But of course, mixed with all this, and covering it all, there is a bubbling, sparkling fountain of effervescent raillery—cruel, personal, insatiable—the raillery of a demon with a grudge. The manuscript was shown to Frederick, who laughed till the tears ran down his cheeks. But, between his gasps, he forbade Voltaire to publish it on pain of his most terrible displeasure. Naturally Voltaire was profuse with promises, and a few days later, under a royal licence obtained for another work, the little book appeared in print. Frederick still managed to keep his wrath within bounds: he collected all the copies of the edition and had them privately destroyed; he gave a furious wigging to Voltaire; and he flattered himself that he had heard the last of the business.
Ne vous embarrassez de rien, mon cher Maupertuis [he wrote to the President in his singular orthography]; l'affaire des libelles est finie. J'ai parlé si vrai à l'hôme, je lui ai lavé si bien la tête que je ne crois pas qu'il y retourne, et je connais son âme lache, incapable de sentiments d'honneur. Je l'ai intimidé du côté de la boursse, ce qui a fait tout l'effet que j'attendais. Je lui ai déclaré enfin nettement que ma maison devait être un sanctuaire et non une retraite de brigands ou de célérats qui distillent des poissons.