A lot of children lose sleep over the dilemma of bedtime with the lights off. It conjures many thoughts and breeds the perfect nightmares. Associated with the dark are tales of creatures lurking behind the shadows, ready to feast on young flesh. Werewolves wait for the coming of midnight, announcing their metamorphosis with horrid howls. Count Dracula carefully counts the hours of daylight before emerging from his coffin for his nightly blood raids. There’s just so many things that can’t be seen in the dark that are ready to kill you. “Can you leave the lights on, mommy?” says young Jimmy, as he looks at his mom who’s about to leave the room. She stops by the door, puts her finger on the switch, turns to face Jimmy then says “sure, son.” The switch is turned off. It goes dark. But light is coming out of his mom’s eyes.
The “dark” connotes many unpleasant things. Racists the world over have used dark skin tones to judge the supposed inferior character of black people. So much so that many skin care products promise to deliver “whitening” effects to those who use it. This imagery of dark vs light permeates through other forms of appraisals as well, echoing the same damnation. Take for instance our reading of popular history: the age of reason, or the epoch wherein mankind flourished in thoughts, culture, and science is named the Enlightenment – to denote the symbolic burst of brilliant light in scholarship that illuminated many areas of human knowledge. In contrast, the historical age that it preceded wherein mankind was thought to be stuck in the doldrums is called the dark ages.
Francesco Petrarca, the famous Italian poet laureate better known by his anglicized name Petrarch, was the first to delineate this historic period as dark in a letter he wrote in 1359. For him, this epoch represented a time of tenebrae, darkness, which was the result of the collapse of pagan Rome. Petrarch believed that the beacon of western civilization was ancient Rome, and it was the influence of outside cultures – in one instance Petrarch, through the person of Lucius Scipio, alludes to them as “strangers of Spanish and African extraction” – that was responsible for its downfall, and hence, the loss of light. Lux will only begin to penetrate the dark, Petrarch thought, if Rome were to be revived. There was hope in his mind for better days, that if “darkness has been dispersed, our descendants can come again in the former pure radiance.” The program Petrarch had in mind was a cultural revival of pagan Roman values, strongly worded in his belief that “Rome would rise up again if she but began to know herself.”
This idea found currency in enlightenment thought with Condorcet, Kant, Voltaire, and others brandishing the Petrarchan torch. However, their fire burned with a more rabid secular flame against the Catholic Church, which at that time was central in censoring the movement and propagation of ideas. Enlightenment thinkers believed that the church’s unchallenged wide-reaching clout, stemming from the fall of Rome, gave rise to ultra-clericalism that effectively stifled the progressive legacies of Hellenistic Greece and ancient Rome. According to the enlightened, Rome knowing herself was not enough to bring back the light, it was also imperative that the church be destroyed.
As the world welcomed the 20th century, embers from the darkness were unearthed. Advancements in modern historiography changed the enlightenment narrative little by little. The light it brought forth revealed many interesting findings.
It looks like the dark ages wasn’t so dark after all.
In corrected and updated versions of history journals and textbooks, the period referred to as the dark ages is alternatively named the middle ages, often still beginning with the downfall of Rome and ending when the renaissance hatches out of its shell. This move was largely spurred by the efforts of a French physicist whose works were kept silent for four-decades, and more perhaps, if it weren’t for his daughters relentless fight to keep her father’s legacy alive. His name was Pierre Duhem (1861-1916).
Students of chemistry and/or physics may have heard of his name before. For those who haven’t, try to see if you have a chemistry or physics textbook lying around, if you do then browse the section on thermodynamics. Chances are you’ll see Duhem’s name partnered to another to describe various equations and relations. There’s the Duhem-Margules and Duhem-Gibbs equations that are still fundamental in physical chemistry and engineering. Though seemingly prominent in the pantheon of scientific greats nowadays, Duhem never enjoyed the same prestige during his living years.
Pierre Maurice Marie Duhem was born in Paris to Flemish parents. He showcased astute intelligence through excellence in academics in his early years and at the age of 11 was sent to Collège Stanislas, an elite private school in Paris. His years in Stanislas was important in his scientific training, abated by the presence of a capable instructor by the name of Jules Moutier, who according to Duhem “planted in us our admiration for physical theory and the desire to contribute to its progress.” Not only did he excel in the sciences, but he also made great strides in mathematics, Greek, and Latin. The latter two being extremely useful in his later historical studies.
When it was time to move on to higher education, Duhem took the entrance exams to two of Paris most prestigious institutions, École Polytechnique and École Normale Supérieure. He placed first in both exams. His father wanted him to enroll in École Polytechnique in the hopes that he’ll land a career as an engineer; his mother wanted him to study the humanities in École Normale Supérieure as a way to steer him away from the sciences which she saw as a deterrent to their Catholic beliefs. He chose neither, but he enrolled in École Normale Supérieure to study the sciences in 1882.
Although he was only in his third-year at École Normale, Duhem felt confident enough to earn a doctorate by submitting a thesis titled Le potentiel thermodynamique et ses applications à la mécanique chimique et à l’étude des phénomènes électriques. While it seemed that he was ready to move on to more advanced theoretical studies, the academic world wasn’t quite ready to open its doors to this young burgeoning intellect; not exactly for the right reasons anyway.
The thesis was rejected.
A controversy was brewing. The breadth of the paper was far-reaching and its tendrils trespassed into territories not meant for neophytes. One of Duhem’s ideas went against the prevailing idea at that time which went to say that substances react with one another following the most exothermic path – in short, the chemical reaction to be expected is the one with the most heat exerted. It was an idea called the “Principle of Maximum Work”. According to Duhem, this principle didn’t work too well in the face of the mathematics involved in analyzing chemical processes. And in the first place, it fails to explain processes that are not exothermic.
Posterity judges Duhem to be right in this regard, but Duhem lived in the past.
It is said that the get a right point across, a wrong one must be removed. For Duhem to have his idea accepted as the correct one, the reigning idea had to be replaced. Unfortunately, the idea that Duhem’s work attacked was put forward by Marcellin Berthelot, one of the leading French authorities in science. Berthelot had many connections, and was well placed in society to have enough political influence to shut down any criticism of his work. This encounter with Berthelot was the first of many that defined Duhem’s banishment and censure from Parisian institutions. It was also the prelude to Duhem’s lifelong struggle against a stubborn scientific establishment.
So what did Duhem do as a response? He published his thesis in 1886 anyway. He also wrote another PhD dissertation. This time it was on magnetism and mathematics. A panel that included one of the world’s greatest mathematicians, Henri Poincaré, accepted the thesis. Duhem received his PhD in 1888.
What followed was a string of appointments in institutions outside Paris. He lectured in Faculté des Sciences in Lille (now Lille University of Science and Technology) from 1886 to 1893. While at Lille he was able to meet Adèle Chayet who he married in 1890. When tragedy struck and took Adèle’s and their second daughter’s life, he transferred to Rennes in 1893. The rendezvous in Rennes was short-lived and in 1894 he accepted an appointment to teach theoretical physics in the University of Bordeaux. While on the move, Duhem never lost sight of Paris, a fact made painfully obvious when his letter of application to teach in Paris was rejected in 1901.
It was during his time in Bordeaux that Duhem first immersed himself in the history of science. While poring over notes and materials for a project titled Les origines de la statique in 1904, he encountered a name that was quite unknown in his time: Jordanus de Nemore. Duhem was baffled, who is this guy? Upon further investigation, it turned out that de Nemore was a mathematician from the 13th century who made interesting contributions in mathematics. The more Duhem read about de Nemore, the more he found references to older works, treatises and texts that were from the dark ages. This seemed problematic to Duhem who in earlier publications also echoed the ideas of his time which was dismissive of the dark ages‘ contribution to science. Les origines de la statique was Duhem’s shift in thinking, and it marked a new phase in his historical research which culminated in two groundbreaking texts.
The first was a work titled Etudes sur Léonard de Vinci. For this project, Duhem carefully consulted the notebooks of Leonardo da Vinci, which he studied in the Bibliothèque Nationale from 1906-1913. Thiis work outlines an unbroken continuity of thought, that starts from the ancients, then moves on to antiquity, to the dark ages, and to the renaissance. According to Duhem, the enlightenment notion that believed the dark ages to be a period of barbarism and stagnation was symptomatic of the modernity being “ill-informed about the history of human thought”.
His second work, which was more ambitious in scope, would carry this argument to greater lengths – it was a history of mankind’s attempts to understand cosmology. Originally planned as a 12-volume series, Le Système du monde was a project that Duhem started in 1913 up to his death in 1916. He was only able to write ten-volumes (nine complete ones and one unfinished), and of the ten, only four saw publication in his lifetime.
Reception of this work was lukewarm at best and outright contemptuous at worst. Though some saw its revolutionary scope, most were dismissive simply because they were reluctant to allow the dark ages any semblance of color. George Sarton, famously known as the “father of the history of science” positively reviewed the first volume, in the journal Isis (the most prestigious journal for the history of science, to which Sarton was also its editor). Not a word of it was heard from Sarton ever since. To add insult to injury, Sarton allowed a 1936 article by Benjamin Ginzburg criticizing Duhem almost personally. The paper starts from the get-go by claiming that much of the evidence Duhem uses to support his thesis regarding Jordan de Nemore’s contribution to modern statics is “palpably far-fetched”. Ginzburg goes on in the paper by questioning Duhem’s competence as a physicist, even stating that the “scientifically-informed person” will no doubt question Duhem’s program.
One speculation why Duhem received such animosity from the scientific establishment was that his work gave credence to Catholic priests and monks like Thomas Bradwardine of the Oxford Calculators, Domingo de Soto of the Spanish Dominican order, and Giovanni di Casali of the Italian Franciscan order, whose mathematical works on free-falling bodies preceded that of Galileo. Even in the face of actual facts, to trace the roots of the scientific revolutions of the 18th-century back to dark age Catholic thinkers was almost anathema – the realization that Newton’s first law of motion was described first by Catholic clerics Nicole Oresme and Jean Buridan was a hard pill to swallow for secularists. It clearly went against the popular argument being parroted at that time (and still is today). If it were clericalism and religious belief that stifled scientific progress, then how were these clerics and priests able to contribute to mathematical and scientific thought?
Two world wars would pass before the other volumes were published. In that long delay was Duhem’s daughter, Hélène, who stopped at nothing to have his father’s magnum opus published. It was a very long battle for Hélène: a battle that included legal squabbles, mendacious manipulations, and almost poverty. Nearly 40-years after the death of her father, the rest of Duhem’s Le Système du monde was published in serial from 1954-1957. The complete publication of this monumental work was first and foremost the triumph of Duhem’s intellect and ultimately the victory of Hélène’s will.
The light of Duhem’s works still shines today. He also made important contributions to the philosophy of science (see: Duhem-Quine thesis). In the fields that he worked on, he left impregnable marks that helped illuminate thought for future generations. By giving light to the past, seeing the future became clearer. Science rarely moves in revolutionary leaps, but it marches on continuously in varying tempos from one epoch to another. Duhem believed that it is in learning from past masters, like how da Vinci learned from dark age sages, that science can move forward. Denying the works by previous scholars simply by the creed of their faith impedes the flight of knowledge. It shackles its wings with the claws of prejudice and wounds its flesh with petty injuries. Ironic, that in this series of slapdash censorship, those who sought to discredit Duhem and block any light from permeating into middle age scholarship were all influenced by the enlightenment, people who believed in the noble cause of setting knowledge free from fetters.
For Hélène, seeing her father’s remaining works published was a moment of jubilation – of her waving the book up high akin to a flag being waved to signal success. It was a symbol that might have told her that she could sleep soundly at last without having to bother about anything ever again – especially whether the lights are turned on or off. For no fears of the dark could come her way again, nor to anybody. The dark was a misunderstood place riddled with haphazard persecutions but bountiful with waiting treasures in the shadows. Her father was one of the first to dive into the dark, and he came back richer in knowledge.
You might want to leave the lights off tonight when you sleep as an experiment. Who knows what will come and what you can find. You might end up like Duhem. Even modern scientists are beginning to realize that. If you’re not convinced, just remember, the dark matters.
Jaki, Stanley. Uneasy genius: the life and work of Pierre Duhem. 1st ed. New York, USA: Springer Publishing. 1987
Nye, Mary Jo. Before big science: the pursuit of modern chemistry and physics, 1800-1940. Harvard: Harvard University Press. 1999
Mommsen, Theodore. (1942). Petrarch’s conception of the “Dark Ages”. Speculum. 17(2). 226-242.