Marat's Science



In the late 1770s Marat began to undertake a career change from physician to physicist. Although he would remain in the medical service of the comte d’Artois until 1783, he began to devote a considerable amount of time to the study of physical phenomena. Eventually this would become his full-time occupation. Throughout the 1780s, up to the eve of the Revolution, Marat dedicated himself to investigating and writing about the physical properties of heat, light, and electricity. The numerous volumes that he published on these subjects describe literally thousands of experiments and observations. These works are more than empirical reports of experiments, however; Marat also attempted to offer a broad theoretical account of the phenomena.

Before Marat’s scientific endeavors can be evaluated they must be separated from the légende noire that emerged in reaction to the Revolution’s most radical phase. The development of science during the French Revolution has frequently been portrayed by reactionary ideologues as a struggle won by partisans of modern science, symbolized by Antoine Lavoisier, over the retrograde forces of “Jacobin science,” epitomized by Marat.[1]

According to this schema, Marat and the other radical revolutionary leaders were implacably hostile to science. First of all, they shared Rousseau’s view that the growth of scientific knowledge had not brought about an improvement in the human condition but, to the contrary, had caused modern society to become less virtuous and less happy. Then during the Revolution, the story goes, once the radicals took power they acted on this premise by destroying the Academy of Sciences, driving its leader, Condorcet, to his death, executing the most important French scientist of the age, Lavoisier, and declaring that the Republic had no need of scientists.[2]

Historian of science Henry Guerlac acknowledged “the persistent tradition that the spirit of the Revolution was detrimental, if not actually antagonistic, to science,” but denied its validity. Nonetheless, Guerlac himself was one of the most important scholars of recent years to perpetuate that tradition. He identified Bernardin de Saint-Pierre and the “charlatanesque” Marat as part of a group of Rousseau’s followers

who clarified his thought, and kept up a sustained drum-fire against the Academic science of which Newton was the symbol, against the Academy of Sciences itself, and against Lavoisier as its dominating figure.[3]

Roger Hahn, the leading modern historian of the Academy of Sciences, has challenged this interpretation. He firmly denies that

learned societies were destroyed as part of a program of intellectual vandalism in which both the Jacobins and the lower classes of French society reveled. . . . All the earlier critics of the Academy, including Bernardin de Saint-Pierre and Marat, were careful to limit their accusations to the personal or communal habits of men who practiced science. Individual scientists might be accused of being dishonest or avaricious and institutions despotic or obsolete, but knowledge itself was hardly ever maligned.[4]

The most lurid charge against Jacobin science—that Marat’s blind hatred of the Academy of Sciences was responsible for Lavoisier’s execution—will be examined below. First, however, some aspects of Marat’s scientific career should be recounted. In the most important sense, that career is extraordinarily well documented: His published books give account in meticulous detail of exactly how he performed his innumerable experiments, including precise illustrations of the apparatus he designed and used and the names of the instrument makers who constructed it for him.

 A great deal of his time was spent in a darkroom laboratory of the type commonly utilized in the eighteenth century for optical experimentation. The piece of scientific equipment most characteristic of his work was an instrument he designed: He called it a “helioscope,” or solar microscope.


A solar microscope similar to Marat’s helioscope. This one was from the laboratory of Marat’s rival, J.A.C. Charles.

© Musée des Arts et Métiers, Paris/Photo Studio CNAM

Less well documented are the circumstances of Marat’s personal life during this period. Some facts are known about where he lived and worked, who his patrons, friends, and scientific colleagues were, how well he managed to live, and what the state of his health was, but the total picture is sketchy.

In general, his financial support seems to have come from patronage by the same aristocrats who formed the patient list of his medical practice. He lived well enough to rub elbows with the rich and famous on a regular basis, at least through the early 1780s. It may seem odd that the future People’s Friend would have a personal servant, but he did indeed, for a time at least, have a young man named Nicolas Dumoulin in his employ as a laquais.[5] Although Marat’s books may have produced some income, they most likely did not bring in enough to cover the costs of his research as well as his upwardly mobile lifestyle.

There is some evidence of a downturn in his fortunes in the later years of the decade prior to the Revolution. The animosity of the Academy of Sciences was clearly putting his scientific career in jeopardy. Some authors have speculated that a crisis in his personal situation was the catalyst that ignited his revolutionary fervor. His personal “failure,” they suggest, unbalanced his mind with desire for revenge against the society that had spurned him.[6] This hypothesis is based on rather thin evidence. It is likely that he had a serious bout of illness in 1788—he later said he thought he had been on his deathbed[7]—and his financial situation may well have deteriorated, but it is impossible to know with certainty. In any event, the claim that Marat’s revolutionary spirit stemmed from a disturbed mind is simply reactionary psychobabble.

The most intense period of his experimental activity took place from about 1778 to 1782; his three major works on heat, light, and electricity were published in early 1780, late 1780, and 1782, respectively. His initial contacts with the Parisian Academy of Sciences occurred in late 1778; by the middle of 1780 his relations with that institution had soured and by 1782 they were ruined beyond repair. In the provincial academies, however, he had influential friends as well as enemies, and he continued to have productive relations with some of those academies throughout most of the 1780s. During the last half of 1783 he pursued an appointment as president of a projected national academy of sciences for Spain, but to no avail.

In 1786 Marat published a French translation of Newton’s Opticks. His last major scientific publication, Mémoires académiques (a collection of four essays he had submitted to provincial academies), appeared early in 1788. He continued to involve himself in scientific controversies throughout 1788 and early 1789 until the rise of the Revolution swept all other concerns aside.

Marat’s amour propre and the pursuit of gloire

Marat’s stated motives for becoming a scientist have frequently been misconstrued, partially as a result of certain semantic shifts. Marat often claimed that he was motivated by “amour propre” and a quest for “gloire.” To the modern ear these phrases, especially when translated into English, carry an uncomfortable connotation of narcissism and insufferable egotism.

Although amour propre can be translated literally as “self love,” its spirit is better rendered by “self esteem,” a rather more socially acceptable sentiment. As for gloire, Marat’s usage was linked with Rousseau’s and was a commonplace of the era. It is perhaps better translated as “honor” than “glory”; its meaning had more to do with wanting to be of service to humanity than wanting to be an object of veneration. None of this has much to do with what Marat’s real motives may have been, of course, which are unknowable, but putting his words into proper context softens the implication of disproportionate self-importance that has been used to suggest mental imbalance. Furthermore, psychohistorians who have perceived megalomania in Marat’s challenge to Newton’s optical theories have simply assumed that Marat’s critique of Newton was worthless—a false assumption, as will be seen below.

The Breadth of Support for Marat’s Research

Marat’s stature as a scientist was in fact analogous to his earlier medical reputation. He was able to attract wealthy and important patrons to support his research. Although some leading professional scientists, incuding Condorcet, Lavoisier, and Laplace, called him a charlatan, he enjoyed considerable prestige as a scientist among broad segments of the educated population, as the following observations demonstrate:

(1) His books on physics were taken seriously enough to be published in German translation, to be favorably reviewed by prominent journals, and to be cited in the works of other natural philosophers and scientists, including members of the Academy of Sciences.

Christian Ehrenfriend Weigel (1748-1831) of the medical faculty of the University of Greiswald translated Marat’s three main works on fire, light, and electricity into German; they were published at Leipzig by S.L. Crusius in 1782, 1783, and 1784, respectively.[8]

Favorable reviews or announcements of Marat’s works appeared in the Journal de physique,[9] the Journal de Médicine,[10] the Journal de littérature, des sciences et des arts,[11] the Courrier de l’Europe,[12] the Journal de Paris,[13] the Journal Encyclopédique,[14] L’Année littéraire,[15] the Nouvelles de la république des lettres,[16] and numerous other periodicals.[17]

Authors who cited Marat’s work favorably included Academy members Lamarck, Lacépède, and Sage, as well as Romé de l’Isle, Van Swinden, Goethe, Marivetz, and Carra.[18]

Perhaps most noteworthy is that Marat’s French translation of Newton’s Opticks has stood the test of time; it is truly remarkable that more than two hundred years later it is still in print.[19]

(2) Marat submitted numerous essays on scientific subjects for competitions sponsored by provincial academies, some of which won prizes and honorable mention.

Between 1778 and 1787 Marat entered essay competitions sponsored by the academies of Dijon, Rouen, Lyon, Bordeaux, and Montpellier.[20] In 1783 his entry on medical uses of electricity won the first prize, a gold medal valued at 300 livres, in a competition set by the Academy of Rouen.[21] His two submissions on Newtonian color theory to a competition set by the Lyon Academy in 1784 did not win, but were cited by the judges as the best of those that had opposed the Newtonian view.[22] In 1785, Marat’s entry in another Rouen competition won honorable mention. Then the following year he again took Rouen’s first prize, this time for an essay challenging Newton’s explanation of colors in soap bubbles and other thin films.[23]

(3) Marat was a serious candidate for the directorship of a national academy of sciences that was to be established in Spain.

In 1783 one of Marat’s wealthy backers, Philippe Roume de Saint Laurent, represented Marat’s interests in negotiations with the government of Spain to win him the presidency of a projected Spanish Academy of Sciences.[24] Spain’s chief minister, Floridablanca, directed his ambassador in Paris, the comte d’Aranda, to meet Marat and sound him out. D’Aranda reported back to Floridablanca that he had gone to see Marat

and asked him his intentions. He told me he wanted 24,000 livres while he was in Spain and 12,000 livres when he retired and that St. Laurent was empowered to arrange the conditions. I went to see some of his experiments. He knows that he has genius and talent. . . . He is a doctor by profession and has a good reputation.[25]

In a later letter to Floridablanca, d’Aranda suggested that Spain might be able to bargain Marat down to an 18,000-livre annual salary. As the negotiations progressed, however, it became apparent that Marat’s reputation was not universally good; that in fact some influential figures in the world of Parisian science considered Marat to be a charlatan. In the end, Marat was not offered the job, but it is undeniable that he had been seriously considered.

(4) Members of the Academy of Sciences, together with Benjamin Franklin, observed, participated in, and expressed appreciation of some of Marat’s experiments.

The Academy of Sciences twice appointed commissions to witness and report on Marat’s work. In the first episode, Franklin joined academicians Le Roy and Sage in a series of visits to Marat’s laboratory for demonstrations of his solar microscope.[26] The official report of this first commission was highly favorable to Marat.[27]

In the second episode, academicians Le Roy and Cousin undertook a long series of observations of Marat’s optical experiments. This time, however, their report was pointedly brief and noncommittal.[28]

Meanwhile, Marat’s public demonstrations were attracting widespread interest. Allesandro Volta, “so famous for his experiments on electricity,” had reportedly been “curious to see those announced by Marat.”[29] This account of Volta’s visit to Marat’s laboratory adds, however, that a sharp dispute between the two electricians occurred, leaving mutual enmity in its wake.

(5) In addition to Marat’s own public demonstrations of his experiments, a number of other savants offered public lecture courses and university physics courses based upon Marat’s discoveries.

In February 1780, a Mr. Paté, professor of physics at Châlons-sur-Marne, made a trip to Paris to meet Marat and discuss his experiments.[30] In June, Paté wrote to tell Marat that he had already announced the project of “making your precious discoveries known in the schools of Reims and Châlons,” and that the announcement had met with an enthusiastic response.[31]

In April 1780, the abbé Jean Jacques Fillasier, member of several provincial academies, advertised a series of eight lecture-demonstrations based on Marat’s Découvertes sur le feu; he announced further lecture series in May and June.[32] In July 1782 Pilâtre de Rozier announced a physics course intended to “make known all the experiments that Mr. Marat has demonstrated in the presence of the members of the Academy.”[33] (The following year, 1783, Pilâtre de Rozier would earn enduring fame as the first aeronaut for his ascension in a balloon over Metz. In 1785 he became the first martyr to the new technology of flight, perishing when his balloon exploded in fire during an attempted crossing of the English Channel.[34]) In March 1783 another physicist, the abbé Miollan, advertised a course on Marat’s heat, light, and electrical experiments.[35]

Marat’s physics attracted devoted followers. Among them were two of his most important future political enemies: Jacques Pierre Brissot de Warville and Charles Barbaroux, both of whom were to play important leadership roles in the Girondin tendency.[36]

(6) A number of socially prominent people admired Marat’s scientific work and helped advance his career as a physicist.

The marquis de l’Aubespine was among Marat’s most important patrons; through him and his wife, the marquise, Marat gained access to Choiseul at the royal court. It was at the de l’Aubespine residence in Paris that Marat established his laboratory. The comte de Maillebois served as an intermediary for Marat with the Parisian Academy of Sciences. The duc de Villeroy, governor of Lyon, was his intermediary with the Lyon Academy. The chevalier de Joubert, treasurer-general of the estates of Languedoc, was his go-between with the Montpellier Academy; Joubert also provided laboratory space for Marat in his home in Paris. The comte de Nogent and the baron de Feldenfeld represented Marat in correspondence with the Dijon and the Rouen academies, respectively.[37] The comte de Wallis wrote to the Journal de Paris insisting that its editors publish reviews of Marat’s work; they complied. Likewise, the celebrated Beaumarchais, author of The Barber of Seville and The Marriage of Figaro, wrote a strong letter to the Mercure de France protesting that journal’s failure to review Marat’s Découvertes sur la lumière. The vicomte de Montigny wrote to another journal praising Marat’s laboratory demonstrations.[38] Nicolas Beauzée, an influential scholar and member of the prestigious Académie français, put his name on Marat’s translation of Newton’s Opticks to insure its publication.

The comte de Tressan, lieutenant-general of the King’s armies, was a warm supporter of Marat’s research. Tressan himself wrote a two-volume treatise on electricity; his views on the subject had much in common with Marat’s.[39] Tressan’s attraction to Marat is particularly interesting since Condorcet, in an official Academy of Sciences eulogy, praised Tressan for a “philosophic spirit” that made him “a barrier against charlatanism.”[40]

Taken together, this evidence should suffice to establish that Marat was a recognized participant in French scientific activities of the 1780s, and that he enjoyed a good reputation as a scientist in important intellectual milieus. While his contributions never became a central focus of scientific discussion in the fields in which he participated, his work was widely known and discussed.


Nevertheless, Marat’s life has been subjected to intense scrutiny and no fact that appears to put him in a positive light has gone unchallenged by his detractors. It has been alleged, for example, that some of the positive journal reviews were written by Marat himself, and that the recognition accorded him by the academies of Rouen and Lyon was less than spontaneous; Marat is said to have manipulated their award committees.

There is no denying that Marat was an aggressive self-promoter; his dependence upon patronage required it. It is quite likely that he was indeed the anonymous author of some of the glowing journal reviews of his own work. In an exchange of letters with Journal de physique editor Delamétherie, for example, Marat appears to be complaining that Delamétherie had altered a review of Mémoires académiques that Marat had submitted to him.[41] The edited version was not hostile but it had omitted an explicit endorsement of Marat’s anti-Newtonian optical conclusions.

One would think that as editor Delamétherie’s right to determine the content of unsigned material would be taken for granted. His answer to Marat, however, reveals that he felt the need to justify his action. Marat’s attitude would suggest that these journal items were perceived by readers not as critiques by independent reviewers but rather as abstracts for which the author of an abstracted work bore responsibility. In either case, it is evident that in the final analysis the various journals were under the control of their respective editors, and praise of Marat’s work could not have appeared against their will.

As for the provincial academies, the charge is that some of their leading lights were secretly in cahoots with Marat, even to the point of allowing him to formulate some of their prize-essay questions himself, giving him opportunities to smuggle some of his pet theories into the competitions.[42] The evidence of such collusion is circumstantial, but nonetheless compelling. What it seems to reflect, however, is not conspiratorially rigged contests but a sort of run-of-the-mill factionalism wherein Marat’s partisans labored to promote their man’s ideas. This sort of cronyism, which is also evident in the episode of Marat’s candidacy for the directorship of the Spanish Academy, certainly conflicts with the noble ideal of disinterested science. The issue, however, is whether it was atypical or whether it was the norm in eighteenth-century academies.

Olivier Coquard has examined this problem closely in order to obtain “a better grasp of the reality of the provincial academies’ practices.” He concludes that as a general rule these academies’ prize committees made their decisions “under the more or less constant pressure of the various candidates’ partisans. Their verdicts were more a reflection of the clash of forces within the institutions than of the real quality of the competing essays.”[43] The factionalism in the cases involving Marat, then, was no aberration, but represented academic politics as usual.

In any event, the very fact that Marat had cronies, collaborators, or supporters in the provincial academies indicates that he was part of a scientific community rather than an isolated crank. It is particularly revealing that his friends in the provinces were not marginal characters, but included such powerful figures as the duc de Villeroy and the chevalier de Joubert.

The Charles Incident

The most scandalous manifestation of the bad blood between Marat and certain others in the world of Parisian science occurred in March 1783 when he and the physicist Jacques Charles actually came to blows. Charles was not yet part of the scientific elite—he had only begun to study physics in 1779—but he later gained attention for pioneering the use of hydrogen instead of hot air to make balloons ascend, and eventually became a member of the Academy of Sciences. In 1783, however, he was, like Marat, engaged in giving public lecture-demonstrations. One particular lecture series presented by Charles included a considerable amount of criticism of Marat’s optical experiments and conclusions. When Marat got word of it, he confronted Charles.

Their altercation has given rise to a number of legendary tales. One, repeated by Michelet among others, has Charles exposing Marat as a pitiful faker who hid metallic needles inside pieces of resin in order to demonstrate a false claim that resin conducts electricity.[44] A more dramatic tale has Marat interrupting Charles during a public lecture at the Louvre and engaging him in a swordfight, which Marat loses.

Although it seems that a sword was indeed involved in their fight, the documentable facts of the case are more mundane.[45] Marat paid a visit to Charles’s place of residence, presumably to complain about Charles’s lectures. According to Marat’s deposition to the police, as he was turning to leave Charles punched him and, with two accomplices, surrounded him, removed a sheathed sword Marat carried, and broke it to bits. (Doctors, among others, commonly wore swords as a mark of their professional status.) Charles, in his version of the events, does not deny that he jumped Marat, but he claims that Marat had unsheathed the sword first and was acting in a threatening manner. Soon thereafter, Marat challenged Charles to a duel, but—dueling being illegal—the police were alerted (by Charles, perhaps?) and prevented it from taking place.[46]

Marat and the Academy of Sciences

Since Marat’s relations with the Parisian Academy of Sciences ended in bitter recriminations, most historians have assumed that his scientific work was poorly received in general. This conclusion is flawed in three regards: (1) It overlooks the earlier, more positive reception accorded him by the Academy; (2) it treats the Academy as if it were the entire scientific community rather than the elite of that community; and (3) it exaggerates the monolithism of the Academy in the prerevolutionary era.

Marat’s rancorous opposition to the Academy of Sciences was politically significant because to challenge the Academy was to challenge an important institution of the monarchy. It stood for mainstream science not only in the ideological sense, but also as the representative of the state’s power of control over science.

The antagonism that developed between Marat and the Academy of Sciences, however, was not primarily institutional, but originated in differing approaches to science. The Academy was not originally hostile to Marat’s experiments, but was eventually alienated by his attempts to create theoretical frameworks that would explain them in ways that challenged orthodox Newtonian assumptions.[47]

During the last four politically charged years of his life, Marat’s earlier scientific activities were not at the forefront of his concerns, although he did not ignore them entirely. A comprehensive view of his journalistic production from 1789 to 1793 refutes the frequent contention that he continued to be obsessed with hatred or jealousy of the Academy of Sciences, and with Lavoisier in particular. His writings on this subject constitute a minute fraction of his total output.

Marat’s attitude toward Antoine Fourcroy, Lavoisier’s chief ally in the field of chemistry, illustrates that Marat did not allow his antipathy toward the Academy to influence his political judgment. After having lambasted Fourcroy for his role in the Academy, Marat nonetheless publicly supported Fourcroy’s candidacy for election to the Convention.[48] One of the little ironies of history occurred when, upon Marat’s assassination, his seat in the Convention was taken by Fourcroy.

Insofar as there was an obvious connection between Marat’s scientific and political lives, however, it can be located in his relationship to the Academy. The Academy represented the scientific elite of the old regime and would undoubtedly have been among Marat’s political targets even if he had never engaged in scientific pursuits himself. His prior experience with that institution certainly shaped the specific form of his attack, which was expressed most fully and directly in a long pamphlet published in September 1791 entitled Les Charlatans modernes.[49]

Marat’s grievances against the Academy were not groundless. He knew that its leaders had intervened to ruin his opportunity to head the Spanish Academy of Sciences.[50] He also had good reason to believe that their animosity toward him was personal and not due to a lack of scientific ability on his part: Had they not wholeheartedly approved his translation of Newton’s Opticks when they were not aware that it was his work?[51]

As previously noted, Marat’s initial contacts with the Academy were generally favorable from his point of view. There was, however, an element within the institution that seems to have opposed him from the start; he later identified it as “the class of geometers and astronomers, which has formed a terrible cabal against me.”[52] Among the leading lights of this grouping were Laplace, Lavoisier, Condorcet, Lalande, and Bailly.

Before the Revolution, Marat generally confined expressions of his antagonism toward the leaders of the Academy to private correspondence. His public demeanor was more discreet; polemics were for the most part conducted by proxy.

Brissot de Warville

Among Marat’s friends and admirers who wielded their pens on his behalf was a prominent young journalist who was to become one of the Revolution’s most important political figures: Jacques Pierre Brissot de Warville. In 1782 Brissot published a work entitled De la vérité that included an account of a lengthy argument between Brissot and the academician Pierre Simon Laplace over the merits of Marat’s scientific work.[53] Although Laplace was not identified by name, Brissot later acknowledged that the dialogue’s “geometer” and “skeptic” were, respectively, Laplace and himself.[54]

Marat was pleased with what Brissot had written and, according to Brissot’s Mémoires, tried to recruit him as a spokesman and publicist for Dr. Marat. Although Brissot says he declined because he felt Marat was seeking a worshipful disciple, their intellectual camaraderie seems to have lasted until irreconcilable political differences drove them apart after 1789. The view Brissot presents of Marat in his Mémoires is interesting but cannot be taken at face value since it was necessarily influenced by the political bitterness that had developed between them.

Their earlier rapport was based on the compatibility of their scientific outlooks. Brissot’s De la vérité had the character of a prospectus for a multivolume work synthesizing all human knowledge of nature, from physical to social.[55] He did not fulfill that promise, however; as a man of too many projects, his prodigious energies were channeled in other directions. His scientific interests led him to the forefront of the Mesmerist movement where he joined the politicized faction headed by Nicolas Bergasse, which included some of the most important publicists of the coming Revolution.[56]

Brissot’s political path diverged from Marat’s during the course of the Revolution. Brissot’s influence was such that his political faction in the Legislative Assembly was known as the Brissotins. This was the grouping—later named Girondins by the historian-poet Lamartine—that dominated the revolutionary government in the crucial period between the fall of the monarchy and the rise of Robespierre’s Jacobin republic. Although ultraradical in its call to extend the Revolution by means of a military crusade against the crowned heads of Europe, the Brissotin tendency ultimately took a conservative stand on the social question: Its idea of revolution stopped well short of social equality for the propertyless classes. This, of course, led Brissot and Marat to opposite sides of the barricades.[57]

On May 31–June 2, 1793, an insurrection occurred in Paris that ushered in the Jacobin government. The Girondins were driven from power and their leaders arrested. In the Convention and in the streets, Marat was a major leader of these events. Marat’s assassination in July 1793 by one of the Girondins’ supporters sealed their fate: Brissot and twenty other leaders and supporters of the faction were executed at the end of October 1793.

Just a decade earlier, however, in his De la vérité, Brissot had enthusiastically defended Marat’s scientific claims against Newton:

Newton examined light with a prism; he believed that its decomposition was only caused by the prism itself. He did not take into account the preliminary decomposition that occurs at the edges of the hole through which the light enters the darkroom. He failed to grasp the great principle of the decomposition of light at the edges of all objects.[58]

Brissot also lambasted the Academy of Sciences’ persecution of those who “dare to replicate Newton’s experiments,” who “find them erroneous and dare to attack his theory.” In a burst of passion, Brissot exclaimed:

But do not allow their shouts, their declamations, nor their persecution to discourage you in the least, O you who nature has gifted with a genius for observation and an unflagging ardor for research and truth! You who trusts only in experiment and not at all in the authority of great names! You have courageously overthrown the idol of the academic cult and have substituted for Newton’s optical errors a system of well-proven interconnected facts.[59]

“I am writing,” Brissot concluded, “the story of that famous physicist Mr. Marat.”[60]

In his dialogue with Laplace, Brissot recapitulated several themes of the Rousseauian revolt against the narrowness and emptiness of the Newtonian worldview:

The academicians are so presumptuous, so pigheaded in their opinions, that they rarely condescend to examine the new ideas with which they are confronted.[61]

When a geometer (Laplace) was heard to dismiss “a physicist who had announced new experiments on light entirely contrary to Newton’s system” (Marat) as an imbecile, a skeptic (Brissot) leapt to the defense:

skeptic: But Mr. Geometer, an imbecile is capable of neither ideas nor the aptitude to utilize them. How can you believe that a physicist who has done more than six thousand new experiments, written several volumes on physics, and so forth, has neither ideas nor the capacity to put them into practice?

geometer: What! He dares to doubt the infallibility of Newton and he is not an imbecile?

skeptic: But Newton was human and subject to error . . . .

geometer: Newton enjoys universal support; his detractors are obscure writers.

skeptic: And were Newton and Descartes not obscure before they became famous? . . .

geometer: But suppose I prove to you mathematically that Newton’s system is true. Then will you admit that his detractors are imbeciles?

skeptic: But those detractors wave around their books full of figures, too. What can be done with this chaos of numbers? Appeal to nature! Look at the facts, because calculations must be based on facts . . . I would rather trust my senses and nature than your volumes of numbers.

The skeptic then proceeded to enumerate some physical facts, all key elements of Marat’s theory of colors:

That the number of primitive colors is three rather than seven; that the solar spectrum is composed of no more than three colors; that colors are formed simply by decomposition of light at the edge of the hole through which the rays pass.

geometer: These facts are false, absurd, impossible.

skeptic: You remind me of the theologians of the sixteenth century who acted as if words were reasons. Have you seen these experiments?

geometer: No.

skeptic: Have you read the author’s books?

geometer: No.

skeptic: Have you heard him speak?

geometer: No.

skeptic: You have neither seen, nor read, nor heard him, and yet you pass judgment! And you say he is an imbecile!

geometer: I do not need to see, read, or hear him. These ideas contradict Newton, the Academy, and my calculations; therefore they are absurd and I have no need to examine them further.

skeptic: That is precisely how the Aristotelians reasoned against Descartes. . . .

geometer: Good God! What will become of us if we have to examine everything?

skeptic: I agree that the task can be burdensome, but if you want to claim the Academy as the sovereign arbiter of the progress of human knowledge . . . then should it not listen before it condemns?[62]

The skeptic was unable to convince the geometer, who continued to insist that the physicist in question was a fool and his defender devoid of logic. Although this dialogue was written by a master of the publicist’s art and from a strongly partisan viewpoint, it convincingly depicts the irreconcilability of Marat’s views with those of his Academy of Sciences opponents. Marat himself later carried these themes through in his own polemic against academic science, Les Charlatans modernes.

Marat and Lavoisier

Marat’s influence has frequently been blamed for sending Lavoisier to the guillotine. As the most often cited individual crime attributed to “Jacobin science,” it deserves some scrutiny.

Marat cannot be accused of having had a direct hand in Lavoisier’s death on May 8, 1794, because he himself had been murdered ten months earlier. The usual allegation is that his attacks against Lavoisier in Les Charlatans modernes and in Ami du peuple formed the indictment that sealed Lavoisier’s fate. Marat did not single out Lavoisier for special attention, however. While the accusations he leveled against Lavoisier were harsh, they were no more so than those he directed at dozens of other public figures. Another famous scientist and member of the Academy whom Marat targeted, for example, was Jean Sylvain Bailly. Marat held Bailly responsible, as mayor of Paris, for giving the order to fire on demonstrators that resulted in the Champ de Mars massacre.[63]

In his polemics Marat referred to Lavoisier’s position in the Academy, but rarely if ever alluded to his scientific views per se. Marat knew that his readers were not greatly concerned with debates over phlogiston or Newton’s optical theories or even animal magnetism. His attacks centered on Lavoisier’s public functions, particularly his role in the General Farm. Lavoisier had been part of that institution for 25 years and it was the source of his substantial fortune.

The General Farm was not an agricultural entity but a tax farm. Louis XVI’s government financed its activities by legislating taxes, but it did not have its own tax-collecting apparatus. Instead, it sold the exclusive rights to collect taxes to a corporate body consisting of some of the richest men in France. These Farmers General paid the government a large sum of money, which constituted the state’s revenues. To recoup their investment, along with a profit, the Farmers General organized the collection of taxes. The social implications are evident. Tax collection cannot be accomplished without police powers to force compliance. The General Farm, then, was seen primarily as an agent of repression and therefore was among the most hated of old-regime institutions; its members were commonly perceived as “bloodsuckers.”[64]

It was as a member of the General Farm, and not as a scientist, that Lavoisier was sentenced to death. Although he had not been among the wealthiest of the tax farmers, he had taken on a central administrative role that made him one of the most visible. He was not singled out, however; the entire group of 28 Farmers General was arrested, tried, and executed at the same time.

Most significantly, Lavoisier was identified in the public mind with the construction of a wall around Paris in the mid-1780s that was designed to enforce the collection of tariffs on commodities brought into the city. Parisians hated the wall because the tariffs significantly raised the prices of food, wine, and other necessities. Furthermore, those caught trying to smuggle goods into Paris without paying the tariffs were severely punished; sometimes even executed. This repression was perceived by plebeian Parisians as an outrage; the subsequent execution of the tax farmers was thus considered simply a matter of retributive justice. Lavoisier in particular, as the man held directly responsible for building the eighteen-mile-long, ten-foot-high wall around the city with its 54 watchtowers staffed by armed police, could expect little sympathy from those who had suffered as a result of his policies. Earlier, during the insurrection triggered by events at the Bastille on July 14, 1789, 40 of the 54 watchtowers had been demolished by the angry Parisian populace.[65]

Marat, in short, did not fabricate the charges against Lavoisier, although his writings undoubtedly contributed to the wave of indignation that engulfed Lavoisier and his fellow tax farmers.[66] It could not have been a decisive contribution, however; Marat had been removed from the scene long before the wave crested.

Marat’s personal relations with Lavoisier had been minimal. Brissot claims that Marat, early on, had pressed him for an introduction to Lavoisier. Brissot says he declined on the grounds that while he had made Lavoisier’s acquaintance, he really did not feel that he knew him well enough to arrange such an introduction.[67] Whether this tale is true or not, it seems that Marat did meet Lavoisier in 1780 and borrowed a book from him. An inscription by Marat found in a book from Lavoisier’s library reads: “This book of Lavoisier’s was lent to me for my researches on medical electricity in 1780.”[68]


An inscription by Marat in a copy of Experiences sur l’électricité by Jean Jallabert. The book was in Lavoisier’s library.

Photo courtesy of Division of Rare and Manuscript Collections, Carl A. Kroch Library, Cornell University

Later, however, Lavoisier became known to Marat as one of the important members of the Academy of Sciences who opposed his scientific claims. Marat thereafter counted Lavoisier among his personal enemies. Marat could not accept having his work rejected by the Academy, which he thought to be a self-appointed elite restraining the development of science in order to protect its monopolistic privileges. The mutual interactions of his scientific and his political passions are evident here. On the other hand, many other scientists who were excluded from the Academy also rebelled against that elite institution, and gave similar reasons for doing so, but none evolved along the same political lines.[69]

Marat’s ultimately antagonistic relationship with the Academy was not a result of irrational professional jealousy on his part, as many commentators have argued, but was a case of mutual incompatibility. On the one hand, Lavoisier, Condorcet, and Laplace, among others, were fully convinced that Marat was simply a charlatan, not to be taken seriously. Marat was no less convinced that Lavoisier, Condorcet, and Laplace were charlatans, using their institutional authority as a shield against the scrutiny of their science by independent scientists such as himself. There was no common ground on which their differences could have been resolved. The Academy attempted to read Marat out of the scientific community, but the Revolution instead drove the Academy out of existence.

The political tide that swept the Academy away cannot be attributed to Marat’s influence alone. The call for abolishing it was broad and strong; Marat lent his voice to the campaign, but his was only one among many. Closing the Academy of Sciences was but a particular manifestation of the Revolution’s general elimination of privileged corporate bodies.

With regard to the reciprocal charges of charlatanism that Marat and Lavoisier leveled against each other, historians have often jumped to the conclusion that since Marat’s was false (witness Lavoisier’s enduring contributions to chemistry), then Lavoisier’s must have been true. The two propositions are not logically connected, however; neither was correct in his characterization of the other as a charlatan.

There is no evidence that Marat ever tried to use his scientific activities to intentionally hoodwink anyone for financial gain. It might be argued that a charlatan could be motivated by the desire for gloire rather than money, but there is still no indication that Marat was trying to convince others of anything that he himself did not believe. In any event, the charge of charlatanism was inappropriate. As was suggested above and will be demonstrated in the next three chapters, Marat’s scientific ideas were not the sui generis productions of a crank but were firmly grounded in contemporary physical theory.

Marat published eight large and small works on physical phenomena throughout the decade before the Revolution. Some of these were prospectuses for or summaries of more extensive treatments of the same subjects. The main body of his scientific work is to be found in a trilogy: three substantial volumes devoted to each of his three main concerns in physics: heat, light, and electricity. They were, respectively: Research on the Physics of Fire (Recherches physiques sur le feu, 1780), Discoveries about Light (Découvertes sur la lumière, 1780), and Research on the Physics of Electricity (Recherches physiques sur l’électricité, 1782). Each of these will be examined in the next three chapters.

Historians of Science on Marat: Recent Revaluations

As noted earlier, historians of science have with few exceptions been hostile toward Marat’s scientific endeavors. A scholarly colloquium held in Paris in 1993, however, signaled a far more positive appreciation of Marat’s work in the medical and physical sciences. Whereas historians had traditionally condemned Marat’s criticisms of Newton as foolishness, Michel Blay carefully examined Marat’s optical theory and arrived at a rather different conclusion. “Far from being foolish pedantry,” Blay says, “it is a well-organized theory, but its experimental field cannot be superimposed upon the Newtonian experimental field.”[70] Marcel Boiteux, in a review of Marat’s writings on electricity, exclaims: “Marat competent, clear, and judicious? Who would have believed it? But it is certainly true.” Boiteux concludes that this “very substantial part of Marat’s scientific work undeniably deserves to be chalked up to his credit for posterity.”[71]

The road to an unbiased evaluation of Marat’s science was opened by a generally objective account published by the American historian of science Charles C. Gillispie in 1980. Gillispie can in no sense be considered partial to Marat; in the final analysis he views Marat as a psychopathic enemy of science. Nonetheless, Gillispie weighed certain aspects of Marat’s scientific career and found, to his evident surprise, more substance than he expected. It is worth citing Gillispie’s verdict on Marat in some detail.

In his monumental Science and Polity in France at the End of the Old Regime Gillispie groups Marat with Mesmer in a chapter devoted to examining “examples of the breed” of charlatans. In spite of that, he begins by pointing out that unlike Mesmer, “Marat was no mystifier.”[72]

Aside from certain matters of style, Gillispie deems Marat’s early pamphlets on gleets and eye disease to be a “pair of clear and otherwise creditable medical papers.”[73] He notes that the paper on eye problems reveals that Marat “was already well versed in optics” as early as 1776.[74] As for the prize-winning essay on medical electricity, Gillispie says that “the actual content of Marat’s memoir is marked by good sense and skepticism.”[75]

Discussing Marat’s Recherches physiques sur le feu, Gillispie shows that Marat was no dilettante dabbling in physics in his spare time; “he had assembled a considerable physical laboratory.”[76] Of his experimental work, Gillispie says: “The labor he performed is staggering.”[77] Nor was Marat’s knowledge superficial: “As always, he knew the literature.”[78] This was particularly evident in his investigations of electricity. “However far-fetched his theory,” Gillispie writes, Marat “had mastered the electrical properties of bodies and the various methods of electrifying them.”[79]

Most significant is Gillispie’s assessment of Marat’s experimental practice relative to that of his contemporaries as well as to more universal standards. According to Gillispie, Marat’s experiments

are impossible to distinguish in principle from others by means of which persons then and now recognized to be scientists have explored the world.[80]

Gillispie’s most unexpected finding, perhaps, had to do with Marat’s translation of Newton’s Opticks. Brissot claimed in his Mémoires, written after he and Marat had become bitter political enemies, that Marat had falsified the translation and had sneaked his own theories into the footnotes as a weapon in his war against Newtonianism. Then, Brissot alleged, Marat tricked a gullible old scholar, Nicolas Beauzée, into endorsing it as a ploy to win the approbation of the Academy of Sciences.[81] As would be expected, later authors hostile to Marat have parroted Brissot’s charges.[82]

Gillispie notes, however, that a number of authors “largely favorable to Marat,” also took Brissot’s allegations for good coin.

On this score, it will appear, he needs protection from his friends among historians no less than from his enemies among philosophers. For his is an excellent translation. A careful comparison with the fourth edition of the Opticks, from which Marat worked, requires it to be said in all fairness that he was nowhere unfaithful to Newton’s meaning . . . . In regard to Newton himself, the tone is impeccable, respectful without being adulatory.[83]

Furthermore, he adds, “Marat did append a critical apparatus to his translation, but it is not true that he smuggled his own theory into the notes.”[84]

Finally, some of Gillispie’s observations aim at putting Marat’s critique of Newtonian optics into historical perspective. Gillispie elsewhere expressed the opinion that Goethe’s book on color theory was a work of foolishness[85]; his general assessment of Marat’s optical theories is no less harsh. Nonetheless, he states that the Academy’s negative report on Marat’s optical experiments failed to give some of his contentions

the attention that others like them have turned out to merit. For the matter of primary colors and the question of Newton’s measurements of specific refrangibility have proved far from empty, though the discussion has owed nothing to anyone’s ever having read Marat.[86]

By appealing to what has “turned out,” Gillispie weighs his subject on the scales of later developments in the science of optics, which shifts the focus of historical inquiry away from the period under consideration. Whether or not later developments owed anything to Marat has no bearing on the intrinsic validity of some of his criticisms of Newton, which Gillispie acknowledges.

Gillispie also felt that another aspect of Marat’s critique of Newton deserved mention:

That Newton’s published accounts of how he had reached conclusions is often idealized to the point of misrepresentation is one of the findings of recent Newton scholarship. . . . In general, I should say that Marat’s suspicions of the published work come closer to an accurate intuition about the kind of window-dressing that Newton sometimes put around his findings than does anything else known to me in the eighteenth-century literature.[87]

The positive appreciations of Marat’s work cited here represent a selection of Gillispie’s views on the subject. He views his subject through the eyes of the scientific elite and therefore considers Marat to have been a “would-be physicist” and a charlatan. Nonetheless, Gillispie’s observations demonstrate that Marat—though no “hero of modern science” on the scale of Lavoisier or Laplace—was a serious and legitimate participant in science as it was practiced in France in the 1780s.

In addition to its honesty, Gillispie’s discussion of Marat is noteworthy for being based on an actual reading of the texts. His charge that previous commentators, in France and elsewhere, had not bothered to read Marat’s scientific works was apparently well founded.[88] The next three chapters are based upon a close reading of those works, which must ultimately provide the foundation for interpreting the significant part of Marat’s life that was devoted to science.


[1] See the extensive discussion of “Jacobin science” in Marshall Clagett, Critical Problems in the History of Science.

[2] The apocryphal nature of the famous anecdote was established by James Guillaume, “Un mot légendaire: ‘La République n’a pas besoin de savants’.” Guillaume traced the origin of this “légende haineuse et sotte” to Abbé Grégoire and ranked the scientists Fourcroy and Cuvier among its most effective propagators.

[3] Henry Guerlac, “On the Papers of Gillispie and Williams,” in Clagett, Critical Problems, 319. Jacques Henri Bernardin de Saint-Pierre’s novel Paul et Virginie is a classic of French literature. In spite of the immense popularity of his scientific writings, especially Études de la Nature, he was scorned by the Academy of Sciences.

[4] Roger Hahn, The Anatomy of a Scientific Institution, 223.

[5] See the documents of the Zabielo affair, which occurred on 27 December 1777. Cabanès, Marat Inconnu, 91, 506–8.

[6] Gottschalk, for example, speculates that at the time of the Revolution, if Marat had earlier been admitted to the Academy of Sciences, “instead of being a man nursing a grudge . . . there is every reason to believe that he would have been entirely conservative and well-satisfied with the world, and not a sensitive soul touched to the quick by an alleged injustice.” Jean Paul Marat, 30–31.

[7] Lettre au Président de l’Assemblée Nationale (May 1790), Correspondance de Marat, 142.

[8] The three works Weigel translated were those discussed in chapters 5, 6, and 7 herein.

[9] Journal de physique, vol. XVIII, part I (April 1781), 317–20; (June 1781), 459–65.

[10] Journal de Médicine, vol. LV (1781), 475.

[11] Journal de littérature, des sciences et des arts, vol. VI (1780), 192–204 and 247–58.

[12] Courrier de l’Europe, 15 March 1782, 170; 3 May 1782, 286.

[13] Journal de Paris, 9 June 1780, 659; 12 November 1780, 1,290.

[14] Journal Encyclopédique, June 1780, vol. IV, 532–3; January 1781, vol. I, 38.

[15] L’Année littéraire, vol. XXIX (1782), 283–8.

[16] Nouvelles de la république des lettres, 30 January 1782, 35–6.

[17] For a list of such reviews, see N. B. Mandelbaum, “Rebel as Savant,” 511–3.

[18] Jean Baptiste Louis Romé de l’Isle, L’Action du feu central; Baltazar Georges Sage, Institutions de physique; Jan Heindrich Van Swinden, Recueil de mémoires sur l’analogie de l’électricité et du magnétisme; Johann Wolfgang von Goethe, Zur Farbenlehre; Jean Baptiste Lamarck, Réfutation de la théorie pneumatique; le comte de Lacépède, Essai sur l’électricité naturelle et artificielle; le baron de Marivetz, Physique du monde; Jean Louis Carra, Dissertation élémentaire sur la nature de la lumière, du feu et de l’électricité.

[19] Isaac Newton, Optique. Traduit de l’anglais par Jean-Paul Marat (1787). Edited by Michel Blay.

[20] Mandelbaum has listed twelve such essays (“Rebel as Savant,” 382), but an exact count is not possible because some are known only indirectly and some anonymous memoirs later attributed to Marat may not in fact have been his.

[21] Published in 1784 as Mémoire sur l’électricité médicale.

[22] Both were published in Marat’s Mémoires académiques (1788).

[23] This essay, too, was published in Mémoires académiques.

[24] According to Mandelbaum a Spanish Academy of Sciences had existed in name since 1774 but had been inactive (Mandelbaum, “Rebel as Savant,” 369).

[25] Letter from the comte d’Aranda to Floridablanca, 19 September 1783. Translated and quoted by Mandelbaum, “Rebel as Savant,” 374.

[26] See Marat’s correspondence with Franklin from 1779 to 1783 in Revue historique de la Révolution, vol. III, 1912, 353–61, and Correspondance de Marat, 81–2. Marat’s solar microscope will be discussed in chapter 5.

[27] Registres de l’Académie des Sciences, 1779, 97–100. Marat published it at the beginning of his Découvertes de M. Marat sur le feu, l’électricité, et la lumière (1779).

[28] Marat published the report, followed by his own comments, at the beginning of his Découvertes sur la lumière (1780).

[29] Brissot, Mémoires, vol. I, 201.

[30] Letter from Paté to Marat (23 February 1780), Correspondance de Marat, 73.

[31] Letter from Paté to Marat (3 June 1781), Correspondance de Marat, 73–4.

[32] See announcements in the Journal de Paris, 6 April 1780, 397–8; 16 April 1780, 441–2; 2 May 1780, 506; 4 June 1780, 638. Fillasier had been associated with Marat for a number of years; in 1777 he submitted the account of Marat’s cure of the marquise de l’Aubespine to the Gazette de Santé (see chapter 1 on this website).

[33] Journal de Paris, 5 July 1782, 761.

[34] In neither case was Pilâtre de Rozier alone, but he was the “captain,” so to speak, of both flights. An anonymous pamphlet about the tragedy, Lettre de l’observateur Bon-Sens à M. de * * * sur la fatale catastrophe des infortunés Platre [sic] de Rosier & Romain, has often been attributed to Marat, but I share Gillispie’s doubts (Science and Polity, 319) as to his authorship.

[35] Journal de Paris, 11 April 1783, 420.

[36] Joseph Farington (The Farington Diary) gives the impression that Marat first met Brissot in the cafés of London sometime in the decade preceding 1776, but that is probably not so. Nothing in Marat’s or Brissot’s writings corroborates the assertion.

[37] Some authors have suggested that Feldenfeld was nonexistent—that Marat “invented” him. That has been shown to be untrue. See Coquard, Marat, 456 (n. 47).

[38] Montigny claimed that “a thousand people” had witnessed the wonders of Marat’s laboratory. Journal de Littérature, des Sciences et des Arts, vol. II (1781), 230–1.

[39] Louis Elisabeth de la Vergne de Broussin, comte de Tressan (1705–83); see his letter to Marat (24 July 1780), Correspondance de Marat, 67–8. Tressan’s Essai sur le fluide électrique, considéré comme agent universel (1786) was published posthumously.

[40] Condorcet, Éloges des Académiciens de l’Académie Royale des Sciences, vol. III, 440–56.

[41] The review was in the Journal de physique, February 1788. Marat’s two letters to Delamétherie, dated 18 March and 26 March 1788, are in Correspondance de Marat, 93–5.

[42] See especially Claudius Roux, Marat et l’Académie de Lyon.

[43] Coquard, “Marat et les Académies de province,” in Lemaire and Poirier, eds., Marat homme de science?, 65–93.

[44] Michelet, Histoire de la Révolution française, vol. I, 421.

[45] Coquard, Marat, 152–5.

[46] See Marat’s challenge to Charles and his subsequent letter to Police Lieutenant Lenoir agreeing not to go through with the duel. Correspondance de Marat, 15–16.

[47] Joseph Dauben, “Marat: His Science and the French Revolution,” 235–61.

[48].See Marat, Les Charlatans modernes, in Pamphlets de Marat, 292; and Marat, l’Ami du Peuple, à ses Concitoyens les Électors, in Pamphlets de Marat, 309–12.

[49] Marat, Les Charlatans modernes, in Pamphlets de Marat, 255–96. It was apparently written several years earlier, perhaps as early as 1785.

[50] Lettre à Roume de Saint-Laurent (20 November 1783), Correspondance de Marat, 24.

[51] Marat’s name did not appear on the translation when the Academy of Sciences was asked for its approval. It was submitted by an important literary scholar, Nicolas Beauzée. See Brissot’s and Gillispie’s comments on this affair later in this chapter.

[52] Lettre à Roume de Saint-Laurent (20 November 1783), Correspondance de Marat, 31.

[53] Brissot, De la vérité, 333–40.

[54] Brissot, Mémoires, vol. I, 198.

[55] “These ruminations are but an introduction to a larger work—the first stone, the foundation, of an edifice so vast that even the blueprints are astounding.” Brissot, De la vérité, 1.

[56] See Darnton, Mesmerism, chapters 3 and 4. The politicized faction was known as “the Kornmann group.”

[57] The reference to barricades is figurative; the famous barricades that have come to symbolize insurrectionary risings in Paris did not make their first appearance until 1827. See “The Barricades,” in Georges Duveau, 1848: The Making of a Revolution, 161–81.

[58] Brissot, De la vérité, 77. See Chapter 4 on this website for Marat’s theory of colors.

[59] Ibid., 173.

[60] Ibid., 174.

[61] Ibid., 332.

[62] Ibid., 333–40.

[63] See Gene Brucker, Jean Sylvain Bailly: Revolutionary Mayor of Paris, 119–29.

[64] See McKie, Lavoisier, 374.

[65] See Rudé, The Crowd in the French Revolution, 49. Four of the watchtowers still stand in Paris today.

[66] Of Lavoisier, Condorcet, Bailly, and other scientists who perished during the Revolution, Henry Guerlac writes: “It was as politicians, financiers, and public officials that they were executed, not as men of science.” Guerlac, “Some Aspects of Science During the French Revolution,” 100.

[67] Brissot, Mémoires, vol. I, 213.

[68] The book was Jean Jallabert, Expériences sur l’électricité (1749). It is now in the Lavoisier collection at Cornell University. To my knowledge, no historian or biographer has challenged the inscription’s authenticity.

[69] Roger Hahn, Anatomy of a Scientific Institution, cites Romé de l’Isle, Bernardin de Saint-Pierre, and Delamétherie as examples.

[70] Michel Blay, “Sur quelques enjeux des théories de la lumière et des couleurs de Marat,” in Lemaire and Poirier, eds., Marat homme de science?, 148. See also Blay, “Marat, théoricien de l’optique et critique de Newton” and “Études sur l’optique newtonienne,” in Newton, Optique.

[71] Marcel Boiteaux, “Marat électricien,” in Lemaire and Poirier, eds., Marat homme de science?, 112–3.

[72] Gillispie, Science and Polity, 258, 291.

[73] Ibid., 296.

[74] Ibid., 296.

[75] Ibid., 319.

[76] Ibid., 312.

[77] Ibid., 324.

[78] Ibid., 314.

[79] Ibid.

[80] Ibid., 312.

[81] Brissot, Mémoires, 203.

[82] For example: “He did a new translation of Newton’s Opticks, adding notes and altering the text in such a way as to overturn the great man’s theory. Then he went to the grammarian Beuzée, knowing his weakness of character, and managed to get Beuzée to put his name to this weapon, hiding its purpose from him no doubt” (Maury, L’Ancienne Académie des Sciences, 174–5).

[83] Gillispie, Science and Polity, 320. Gottschalk’s 1927 biography of Marat also noted that his translation of the Opticks was “faithfully executed” (Gottschalk, Jean Paul Marat, 28).

[84] Gillispie, Science and Polity, 321.

[85] Goethe’s work on color theory, which is discussed in Chapter 4 on this website, was Zur Farbenlehre. Gillispie wrote: “It is impossible to read the Farbenlehre without an acute sense of embarrassment at the painful spectacle of the author, a great man, making a fool of himself” (Gillispie, The Edge of Objectivity, 196). A number of scholars who have recently reinvestigated this work of Goethe’s do not concur. See Sepper, Goethe Contra Newton; and Amrine, Zucker, and Wheeler, Goethe and the Sciences: A Reappraisal.

[86] Gillispie, Science and Polity, 307–8.

[87] Ibid., 328.

[88] Mandelbaum is an exception, but Gillispie does not cite his work, which was unpublished.