Roger Bacon

Roger Bacon OFM
Statue of Bacon at the Oxford University Museum of Natural History Statue of Bacon at the Oxford University Museum of Natural History
Born	c. 1219/20 near Ilchester, Somerset, England
Died	c. 1292 (aged about 72/73) near Oxford, Oxfordshire, England
Other name	Doctor Mirabilis
Education
Alma mater	University of Oxford
Academic advisor	Adam Marsh
Philosophical work
Era	Medieval philosophy
Region	Western philosophy
School	Scholasticism
Main interests	Theology Natural philosophy, Natural sciences, Chemistry, Biology, engineering, Mathematics, Astronomy
Notable ideas	Experimental science

Roger Bacon (/ˈbeɪkən/; Latin: Rogerus or Rogerius Baconus, Baconis, also Frater Rogerus; c. 1219/20 – c. 1292), also known by the scholastic accolade Doctor Mirabilis, was a medieval English polymath, philosopher, scientist, theologian and Franciscan friar who placed considerable emphasis on the study of nature through empiricism. Intertwining his Catholic faith with scientific thinking, Roger Bacon is considered one of the greatest polymaths of the medieval period.

In the early modern era, he was regarded as a wizard and particularly famed for the story of his mechanical or necromantic brazen head. He is credited as one of the earliest European advocates of the modern scientific method, along with his teacher Robert Grosseteste. Bacon applied the empirical method of Ibn al-Haytham (Alhazen) to observations in texts attributed to Aristotle. Bacon discovered the importance of empirical testing when the results he obtained were different from those that would have been predicted by Aristotle.

His linguistic work has been heralded for its early exposition of a universal grammar, and 21st-century re-evaluations emphasise that Bacon was essentially a medieval thinker, with much of his "experimental" knowledge obtained from books in the scholastic tradition. He was, however, partially responsible for a revision of the medieval university curriculum, which saw the addition of optics to the traditional quadrivium.

Bacon's major work, the Opus Majus, was sent to Pope Clement IV in Rome in 1267 upon the pope's request. Although gunpowder was first invented and described in China, Bacon was the first in Europe to record its formula.

Life

Roger Bacon was born in Ilchester in Somerset, England, in the early 13th century. His birth is sometimes narrowed down to 1210, 1213 or 1214, 1215 or 1220. The only source for his birth date is a statement from his 1267 Opus Tertium that "forty years have passed since I first learned the Alphabetum". The latest dates assume this referred to the alphabet itself, but elsewhere in the Opus Tertium it is clear that Bacon uses the term to refer to rudimentary studies, the trivium or quadrivium that formed the medieval curriculum. His family appears to have been well off.

Bacon studied at Oxford. While Robert Grosseteste had probably left shortly before Bacon's arrival, his work and legacy almost certainly influenced the young scholar and it is possible Bacon subsequently visited him and William of Sherwood in Lincoln. Bacon became a Master at Oxford, lecturing on Aristotle. There is no evidence he was ever awarded a doctorate. (The title Doctor Mirabilis was a posthumous scholastic accolade.) A caustic cleric named Roger Bacon is recorded speaking before the king at Oxford in 1233.

In 1237 or at some point in the following decade, he accepted an invitation to teach at the University of Paris. While there, he lectured on Latin grammar, Aristotelian logic, arithmetic, geometry, and the mathematical aspects of astronomy and music. His faculty colleagues included Robert Kilwardby, Albertus Magnus, and Peter of Spain, who later became Pope as Pope John XXI. The Cornishman Richard Rufus was a scholarly opponent. In 1247 or soon after, he left his position in Paris.

As a private scholar, his whereabouts for the next decade are uncertain but he was likely in Oxford c. 1248–1251, where he met Adam Marsh, and in Paris in 1251. He seems to have studied most of the known Greek and Arabic works on optics (then known as "perspective", perspectiva). A passage in the Opus Tertium states that at some point he took a two-year break from his studies.

By the late 1250s, resentment against the king's preferential treatment of his émigré Poitevin relatives led to a coup and the imposition of the Provisions of Oxford and Westminster, instituting a baronial council and more frequent parliaments. Pope Urban IV absolved the king of his oath in 1261 and, after initial abortive resistance, Simon de Montfort led a force, enlarged due to recent crop failures, that prosecuted the Second Barons' War. Bacon's own family were considered royal partisans: De Montfort's men seized their property and drove several members into exile.

In 1256 or 1257, he became a friar in the Franciscan Order in either Paris or Oxford, following the example of scholarly English Franciscans such as Grosseteste and Marsh. After 1260, Bacon's activities were restricted by a statute prohibiting the friars of his order from publishing books or pamphlets without prior approval. He was likely kept at constant menial tasks to limit his time for contemplation and came to view his treatment as an enforced absence from scholarly life.

By the mid-1260s, he was undertaking a search for patrons who could secure permission and funding for his return to Oxford. For a time, Bacon was finally able to get around his superiors' interference through his acquaintance with Guy de Foulques, bishop of Narbonne, cardinal of Sabina, and the papal legate who negotiated between England's royal and baronial factions.

In 1263 or 1264, a message garbled by Bacon's messenger, Raymond of Laon, led Guy to believe that Bacon had already completed a summary of the sciences. In fact, he had no money to research, let alone copy, such a work and attempts to secure financing from his family were thwarted by the Second Barons' War. However, in 1265, Guy was summoned to a conclave at Perugia that elected him Pope Clement IV. William Benecor, who had previously been the courier between Henry III and the pope, now carried the correspondence between Bacon and Clement. Clement's reply of 22 June 1266 commissioned "writings and remedies for current conditions", instructing Bacon not to violate any standing "prohibitions" of his order but to carry out his task in utmost secrecy.

While faculties of the time were largely limited to addressing disputes on the known texts of Aristotle, Clement's patronage permitted Bacon to engage in a wide-ranging consideration of the state of knowledge in his era. In 1267 or '68, Bacon sent the Pope his Opus Majus, which presented his views on how to incorporate Aristotelian logic and science into a new theology, supporting Grosseteste's text-based approach against the "sentence method" then fashionable.

Bacon also sent his Opus Minus, De Multiplicatione Specierum, 'De Speculis Comburentibus, an optical lens, and possibly other works on alchemy and astrology. The entire process has been called "one of the most remarkable single efforts of literary productivity", with Bacon composing referenced works of around a million words in about a year.

Pope Clement died in 1268 and Bacon lost his protector. The Condemnations of 1277 banned the teaching of certain philosophical doctrines, including deterministic astrology. Some time within the next two years, Bacon was apparently imprisoned or placed under house arrest. This was traditionally ascribed to Franciscan Minister General Jerome of Ascoli, probably acting on behalf of the many clergy, monks, and educators attacked by Bacon's 1271 Compendium Studii Philosophiae.

Modern scholarship, however, notes that the first reference to Bacon's "imprisonment" dates from eighty years after his death on the charge of unspecified "suspected novelties" and finds it less than credible. Contemporary scholars who do accept Bacon's imprisonment typically associate it with Bacon's "attraction to contemporary prophesies", his sympathies for "the radical 'poverty' wing of the Franciscans", interest in certain astrological doctrines, or generally combative personality rather than from "any scientific novelties which he may have proposed".

Sometime after 1278, Bacon returned to the Franciscan House at Oxford, where he continued his studies and is presumed to have spent most of the remainder of his life. His last dateable writing—the Compendium Studii Theologiae—was completed in 1292. He seems to have died shortly afterwards and been buried at Oxford.

Work

Medieval European philosophy often relied on appeals to the authority of Church Fathers such as St Augustine, and on works by Plato and Aristotle only known at second hand or through Latin translations. By the 13th century, new works and better versions – in Arabic or in new Latin translations from the Arabic – began to trickle north from Muslim Spain. In Roger Bacon's writings, he upholds Aristotle's calls for the collection of facts before deducing scientific truths, against the practices of his contemporaries, arguing that "thence cometh quiet to the mind".

Bacon also called for reform with regard to theology. He argued that, rather than training to debate minor philosophical distinctions, theologians should focus their attention primarily on the Bible itself, learning the languages of its original sources thoroughly. He was fluent in several of these languages and was able to note and bemoan several corruptions of scripture, and of the works of the Greek philosophers that had been mistranslated or misinterpreted by scholars working in Latin. He also argued for the education of theologians in science ("natural philosophy") and its addition to the medieval curriculum.

Opus Majus

Bacon's 1267 Greater Work, the Opus Majus, contains treatments of mathematics, optics, alchemy, and astronomy, including theories on the positions and sizes of the celestial bodies. It is divided into seven sections: "The Four General Causes of Human Ignorance" (Causae Erroris), "The Affinity of Philosophy with Theology" (Philosophiae cum Theologia Affinitas), "On the Usefulness of Grammar" (De Utilitate Grammaticae), "The Usefulness of Mathematics in Physics" (Mathematicae in Physicis Utilitas), "On the Science of Perspective" (De Scientia Perspectivae), "On Experimental Knowledge" (De Scientia Experimentali), and "A Philosophy of Morality" (Moralis Philosophia).

It was not intended as a complete work but as a "persuasive preamble" (persuasio praeambula), an enormous proposal for a reform of the medieval university curriculum and the establishment of a kind of library or encyclopedia, bringing in experts to compose a collection of definitive texts on these subjects. The new subjects were to be "perspective" (i.e., optics), "astronomy" (inclusive of astronomy proper, astrology, and the geography necessary to use them), "weights" (likely some treatment of mechanics but this section of the Opus Majus has been lost), alchemy, agriculture (inclusive of botany and zoology), medicine, and "experimental science", a philosophy of science that would guide the others. The section on geography was allegedly originally ornamented with a map based on ancient and Arabic computations of longitude and latitude, but has since been lost. His (mistaken) arguments supporting the idea that dry land formed the larger proportion of the globe were apparently similar to those which later guided Columbus.

In this work Bacon criticises his contemporaries Alexander of Hales and Albertus Magnus, who were held in high repute despite having only acquired their knowledge of Aristotle at second hand during their preaching careers. Albert was received at Paris as an authority equal to Aristotle, Avicenna and Averroes, a situation Bacon decried: "never in the world [had] such monstrosity occurred before".

In Part I of the Opus Majus Bacon recognises some philosophers as the Sapientes, or gifted few, and saw their knowledge in philosophy and theology as superior to the vulgus philosophantium, or common herd of philosophers. He held Islamic thinkers between 1210 and 1265 in especially high regard calling them "both philosophers and sacred writers" and defended the integration of philosophy from apostate philosopher of the Islamic world into Christian learning.

Calendrical reform

In Part IV of the Opus Majus, Bacon proposed a calendrical reform similar to the later system introduced in 1582 under Pope Gregory XIII. Drawing on ancient Greek and medieval Islamic astronomy recently introduced to western Europe via Spain, Bacon continued the work of Robert Grosseteste and criticised the then-current Julian calendar as "intolerable, horrible, and laughable".

It had become apparent that Eudoxus and Sosigenes's assumption of a year of 365¼ days was, over the course of centuries, too inexact. Bacon charged that this meant the computation of Easter had shifted forward by 9 days since the First Council of Nicaea in 325. His proposal to drop one day every 125 years and to cease the observance of fixed equinoxes and solstices was not acted upon following the death of Pope Clement IV in 1268. The eventual Gregorian calendar drops one day from the first three centuries in each set of 400 years.

Optics

In Part V of the Opus Majus, Bacon discusses physiology of eyesight and the anatomy of the eye and the brain, considering light, distance, position, and size, direct and reflected vision, refraction, mirrors, and lenses. His treatment was primarily oriented by the Latin translation of Alhazen's Book of Optics. He also draws heavily on Eugene of Palermo's Latin translation of the Arabic translation of Ptolemy's Optics; on Robert Grosseteste's work based on Al-Kindi's Optics; and, through Alhazen (Ibn al-Haytham), on Ibn Sahl's work on dioptrics.

Gunpowder

A passage in the Opus Majus and another in the Opus Tertium are usually taken as the first European descriptions of a mixture containing the essential ingredients of gunpowder. Partington and others have come to the conclusion that Bacon most likely witnessed at least one demonstration of Chinese firecrackers, possibly obtained by Franciscans—including Bacon's friend William of Rubruck—who visited the Mongol Empire during this period. The most telling passage reads:

We have an example of these things (that act on the senses) in [the sound and fire of] that children's toy which is made in many [diverse] parts of the world; i.e. a device no bigger than one's thumb. From the violence of that salt called saltpetre [together with sulphur and willow charcoal, combined into a powder] so horrible a sound is made by the bursting of a thing so small, no more than a bit of parchment [containing it], that we find [the ear assaulted by a noise] exceeding the roar of strong thunder, and a flash brighter than the most brilliant lightning.

At the beginning of the 20th century, Henry William Lovett Hime of the Royal Artillery published the theory that Bacon's Epistola contained a cryptogram giving a recipe for the gunpowder he witnessed. The theory was criticised by Thorndike in a 1915 letter to Science and several books, a position joined by Muir, John Maxson Stillman, Steele, and Sarton. Needham et al. concurred with these earlier critics that the additional passage did not originate with Bacon and further showed that the proportions supposedly deciphered (a 7:5:5 ratio of saltpetre to charcoal to sulphur) as not even useful for firecrackers, burning slowly with a great deal of smoke and failing to ignite inside a gun barrel. The ~41% nitrate content is too low to have explosive properties.

Secret of Secrets

Bacon attributed the Secret of Secrets (Secretum Secretorum) (Arabic: Sirr al-ʿasrar), to Aristotle, thinking that he had composed it for Alexander the Great. Bacon produced an edition of Philip of Tripoli's Latin translation, complete with his own introduction and notes; and his writings of the 1260s and 1270s cite it far more than his contemporaries did. This led Easton and others, including Robert Steele, to argue that the text spurred Bacon's own transformation into an experimentalist. (Bacon never described such a decisive impact himself.) The dating of Bacon's edition of the Secret of Secrets is a key piece of evidence in the debate, with those arguing for a greater impact giving it an earlier date; but it certainly influenced the elder Bacon's conception of the political aspects of his work in the sciences.

Alchemy

Bacon has been credited with a number of alchemical texts.

The Letter on the Secret Workings of Art and Nature and on the Vanity of Magic (Epistola de Secretis Operibus Artis et Naturae et de Nullitate Magiae), also known as On the Wonderful Powers of Art and Nature (De Mirabili Potestate Artis et Naturae), a likely-forged letter to an unknown "William of Paris", dismisses practices such as necromancy but contains most of the alchemical formulae attributed to Bacon, including one for a philosopher's stone and another possibly for gunpowder. It also includes several passages about hypothetical flying machines and submarines, attributing their first use to Alexander the Great. On the Vanity of Magic or The Nullity of Magic is a debunking of esoteric claims in Bacon's time, showing that they could be explained by natural phenomena.

He wrote on the medicine of Galen, referring to the translations of Avicenna. He believed that the medicine of Galen belonged to an ancient tradition passed through Chaldeans, Greeks and Arabs. Although he provided a negative image of Hermes Trismegistus, his work was influenced by Hermetic thought. Bacon's endorsement of Hermetic philosophy is evident, as his citations of the alchemical literature known as the Secretum Secretorum made several appearances in the Opus Majus. The Secretum Secretorum contains knowledge about the Hermetic Emerald Tablet, which was an integral component of alchemy, thus proving that Bacon's version of alchemy was much less secular, and much more spiritual than once interpreted. The importance of Hermetic philosophy in Bacon's work is also evident through his citations of classic Hermetic literature such as the Corpus Hermeticum. Bacon's citation of the Corpus Hermeticum, which consists of a dialogue between Hermes and the pagan deity Asclepius, proves that Bacon's ideas were much more in line with the spiritual aspects of alchemy rather than the scientific aspects. However, this is somewhat paradoxical as what Bacon was specifically trying to prove in the Opus Majus and subsequent works, was that spirituality and science were the same entity. Bacon believed that by using science, certain aspects of spirituality such as the attainment of "Sapientia" or "Divine Wisdom" could be logically explained using tangible evidence. Bacon's Opus Majus was first and foremost, a compendium of sciences which he believed would facilitate the first step towards "Sapientia". Bacon placed considerable emphasis on alchemy and even went so far as to state that alchemy was the most important science. The reason why Bacon kept the topic of alchemy vague for the most part, is due to the need for secrecy about esoteric topics in England at the time as well as his dedication to remaining in line with the alchemical tradition of speaking in symbols and metaphors.

Linguistics

Bacon's early linguistic and logical works are the Overview of Grammar (Summa Grammatica), Summa de Sophismatibus et Distinctionibus, and the Summulae Dialectices or Summulae super Totam Logicam. These are mature but essentially conventional presentations of Oxford and Paris's terminist and pre-modist logic and grammar. His later work in linguistics is much more idiosyncratic, using terminology and addressing questions unique in his era.

In his Greek and Hebrew Grammars (Grammatica Graeca and Hebraica), in his work "On the Usefulness of Grammar" (Book III of the Opus Majus), and in his Compendium of the Study of Philosophy, Bacon stresses the need for scholars to know several languages. Europe's vernacular languages are not ignored—he considers them useful for practical purposes such as trade, proselytism, and administration—but Bacon is mostly interested in his era's languages of science and religion: Arabic, Greek, Hebrew and Latin.

Bacon is less interested in a full practical mastery of the other languages than on a theoretical understanding of their grammatical rules, ensuring that a Latin reader will not misunderstand passages' original meaning. For this reason, his treatments of Greek and Hebrew grammar are not isolated works on their topic but contrastive grammars treating the aspects which influenced Latin or which were required for properly understanding Latin texts. He pointedly states, "I want to describe Greek grammar for the benefit of Latin speakers". It is likely only this limited sense which was intended by Bacon's boast that he could teach an interested pupil a new language within three days.

Passages in the Overview and the Greek grammar have been taken as an early exposition of a universal grammar underlying all human languages. The Greek grammar contains the tersest and most famous exposition:

Grammar is one and the same in all languages, substantially, though it may vary, accidentally, in each of them.

However, Bacon's lack of interest in studying a literal grammar underlying the languages known to him and his numerous works on linguistics and comparative linguistics has prompted Hovdhaugen to question the usual literal translation of Bacon's grammatica in such passages. She notes the ambiguity in the Latin term, which could refer variously to the structure of language, to its description, and to the science underlying such descriptions: i.e., linguistics.

Other works

Bacon states that his Lesser Work (Opus Minus) and Third Work (Opus Tertium) were originally intended as summaries of the Opus Majus in case it was lost in transit. Easton's review of the texts suggests that they became separate works over the course of the laborious process of creating a fair copy of the Opus Majus, whose half-million words were copied by hand and apparently greatly revised at least once.

Other works by Bacon include his "Tract on the Multiplication of Species" (Tractatus de Multiplicatione Specierum), "On Burning Lenses" (De Speculis Comburentibus), the Communia Naturalium and Mathematica, the "Compendium of the Study of Philosophy" and "of Theology" (Compendium Studii Philosophiae and Theologiae), and his Computus. The "Compendium of the Study of Theology", presumably written in the last years of his life, was an anticlimax: adding nothing new, it is principally devoted to the concerns of the 1260s.

Apocrypha

The Mirror of Alchimy (Speculum Alchemiae), a short treatise on the origin and composition of metals, is traditionally credited to Bacon. It espouses the Arabian theory of mercury and sulphur forming the other metals, with vague allusions to transmutation. Stillman opined that "there is nothing in it that is characteristic of Roger Bacon's style or ideas, nor that distinguishes it from many unimportant alchemical lucubrations of anonymous writers of the thirteenth to the sixteenth centuries", and Muir and Lippmann also considered it a pseudepigraph.

The cryptic Voynich manuscript has been attributed to Bacon by various sources, including by its first recorded owner, but historians of science Lynn Thorndike and George Sarton dismissed these claims as unsupported, and the vellum of the manuscript has since been dated to the 15th century.

Legacy

Bacon was largely ignored by his contemporaries in favour of other scholars such as Albertus Magnus, Bonaventure, and Thomas Aquinas, although his works were studied by Bonaventure, John Pecham, and Peter of Limoges, through whom he may have influenced Raymond Lull. He was also partially responsible for the addition of optics (perspectiva) to the medieval university curriculum.

By the early modern period, the English considered him the epitome of a wise and subtle possessor of forbidden knowledge, a Faust-like magician who had tricked the devil and so was able to go to heaven. Of these legends, one of the most prominent was that he created a talking brazen head which could answer any question. The story appears in the anonymous 16th-century account of The Famous Historie of Fryer Bacon, in which Bacon speaks with a demon but causes the head to speak by "the continuall fume of the six hottest Simples", testing his theory that speech is caused by "an effusion of vapors".

Around 1589, Robert Greene adapted the story for the stage as The Honorable Historie of Frier Bacon and Frier Bongay, one of the most successful Elizabethan comedies. As late as the 1640s, Thomas Browne was still complaining that "Every ear is filled with the story of Frier Bacon, that made a brazen head to speak these words, Time is". Greene's Bacon spent seven years creating a brass head that would speak "strange and uncouth aphorisms" to enable him to encircle Britain with a wall of brass that would make it impossible to conquer.

Unlike his source material, Greene does not cause his head to operate by natural forces but by "nigromantic charms" and "the enchanting forces of the devil": i.e., by entrapping a dead spirit or hobgoblin. Bacon collapses, exhausted, just before his device comes to life and announces "Time is", "Time was", and "Time is Past" before being destroyed in spectacular fashion: the stage direction instructs that "a lightening flasheth forth, and a hand appears that breaketh down the Head with a hammer".

A necromantic head was ascribed to Pope Sylvester II as early as the 1120s, but Browne considered the legend to be a misunderstanding of a passage in Peter the Good's c. 1335 Precious Pearl where the negligent alchemist misses the birth of his creation and loses it forever. The story may also preserve the work by Bacon and his contemporaries to construct clockwork armillary spheres. Bacon had praised a "self-activated working model of the heavens" as "the greatest of all things which have been devised".

As early as the 16th century, natural philosophers such as Bruno, Dee and Francis Bacon were attempting to rehabilitate Bacon's reputation and to portray him as a scientific pioneer who had avoided the petty bickering of his contemporaries to attempt a rational understanding of nature. By the 19th century, commenters following Whewell considered that "Bacon... was not appreciated in his age because he was so completely in advance of it; he is a 16th- or 17th-century philosopher, whose lot has been by some accident cast in the 13th century". His assertions in the Opus Majus that "theories supplied by reason should be verified by sensory data, aided by instruments, and corroborated by trustworthy witnesses" were (and still are) considered "one of the first important formulations of the scientific method on record".

This idea that Bacon was a modern experimental scientist reflected two views of the period: that the principal form of scientific activity is experimentation and that 13th-century Europe still represented the "Dark Ages". This view, which is still reflected in some 21st-century popular science books, portrays Bacon as an advocate of modern experimental science who emerged as a solitary genius in an age hostile to his ideas. Based on Bacon's apocrypha, he is also portrayed as a visionary who predicted the invention of the submarine, aircraft, and automobile. Consistent with this view of Bacon as a man ahead of his time, H. G. Wells's Outline of History attributes this prescient passage to him:

Machines for navigating are possible without rowers, so that great ships suited to river or ocean, guided by one man, may be borne with greater speed than if they were full of men. Likewise, cars may be made so that without a draught animal they may be moved cum impetu inaestimabili, as we deem the scythed chariots to have been from which antiquity fought. And flying machines are possible, so that a man may sit in the middle turning some device by which artificial wings may beat the air in the manner of a flying bird.

However, in the course of the 20th century, Husserl, Heidegger and others emphasised the importance to the modern science of Cartesian and Galilean projections of mathematics over sensory perceptions of nature; Heidegger, in particular, noted the lack of such an understanding in Bacon's works. Although Crombie, Kuhn and Schramm continued to argue for Bacon's importance to the development of "qualitative" areas of modern science, Duhem, Thorndike, Carton and Koyré emphasised the essentially medieval nature of Bacon's scientia experimentalis.

Research also established that Bacon was probably not as isolated—and not as persecuted—as was once thought. Many medieval sources of and influences on Bacon's scientific activity have been identified. In particular, Bacon often mentioned his debt to the work of Robert Grosseteste: his work on optics and the calendar followed Grosseteste's lead, as did his idea that inductively-derived conclusions should be submitted for verification through experimental testing.

Bacon noted of William of Sherwood that "nobody was greater in philosophy than he"; praised Peter of Maricourt (the author of "A Letter on Magnetism") and John of London as "perfect" mathematicians; Campanus of Novara (the author of works on astronomy, astrology, and the calendar) and a Master Nicholas as "good"; and acknowledged the influence of Adam Marsh and lesser figures. Some scholars have pushed back on his reputation as an isolated genius.

As a result, the picture of Bacon has changed. Bacon is now seen as part of his age: a leading figure in the beginnings of the medieval universities at Paris and Oxford but one joined in the development of the philosophy of science by Robert Grosseteste, William of Auvergne, Henry of Ghent, Albert Magnus, Thomas Aquinas, John Duns Scotus, and William of Ockham. Lindberg summarised:

Bacon was not a modern, out of step with his age, or a harbinger of things to come, but a brilliant, combative, and somewhat eccentric schoolman of the thirteenth century, endeavoring to take advantage of the new learning just becoming available while remaining true to traditional notions... of the importance to be attached to philosophical knowledge".

A recent review of the many visions of Bacon across the ages says contemporary scholarship still neglects one of the most important aspects of his life and thought: his commitment to the Franciscan order.

His Opus majus was a plea for reform addressed to the supreme spiritual head of the Christian faith, written against a background of apocalyptic expectation and informed by the driving concerns of the friars. It was designed to improve training for missionaries and to provide new skills to be employed in the defence of the Christian world against the enmity of non-Christians and of the Antichrist. It cannot usefully be read solely in the context of the history of science and philosophy.

With regard to religion's influence on Bacon's philosophy, Charles Sanders Peirce noted, "To Roger Bacon,... the schoolmen's conception of reasoning appeared only an obstacle to truth... [but] Of all kinds of experience, the best, he thought, was interior illumination, which teaches many things about Nature which the external senses could never discover, such as the transubstantiation of bread." Later scholars have therefore viewed him as a proto-protestant.

In Oxford lore, Bacon is credited as the namesake of Folly Bridge for having been placed under house arrest nearby. Although this is probably untrue, it had formerly been known as "Friar Bacon's Bridge". Bacon is also honoured at Oxford by a plaque affixed to the wall of the Westgate shopping centre.

In popular culture

To commemorate the 700th anniversary of Bacon's approximate year of birth, Prof. J. Erskine wrote the biographical play A Pageant of the Thirteenth Century, which was performed and published by Columbia University in 1914. A fictionalised account of Bacon's life and times also appears in the second book of James Blish's After Such Knowledge trilogy, the 1964 Doctor Mirabilis. Bacon serves as a mentor to the protagonists of Thomas Costain's 1945 The Black Rose, and Umberto Eco's 1980 The Name of the Rose. Greene's play prompted a less successful sequel John of Bordeaux and was recast as a children's story for James Baldwin's 1905 Thirty More Famous Stories Retold. "The Brazen Head of Friar Bacon" also appears in Daniel Defoe's 1722 Journal of the Plague Year, Nathaniel Hawthorne's 1843 "The Birth-Mark" and 1844 "The Artist of the Beautiful", William Douglas O'Connor's 1891 "The Brazen Android" (where Bacon devises it to terrify King Henry into accepting Simon de Montfort's demands for greater democracy), John Cowper Powys's 1956 The Brazen Head, and Robertson Davies's 1970 Fifth Business. Bacon appears in Rudyard Kipling's 1926 story 'The Eye of Allah'.

See also

• Baco, a lunar crater named for Roger Bacon
• History of geomagnetism, of translation, of the scientific method, and of science in the Middle Ages
• John of St Amand
• List of Catholic clergy scientists
• Oxford Franciscan school
• Roger Bacon High School
• Vitello
• Wilfrid Voynich

From the 1913 Catholic Encyclopedia

Roger Bacon — Philosopher, surnamed DOCTOR MIRABILIS, b. at Ilchester, Somersetshire, about 1214; d. at Oxford, perhaps 11 June, 1294. His wealthy parents sided with Henry III against the rebellious barons, but lost nearly all their property. It has been presumed that Robert Bacon, O.P., was Roger's brother; more probably he was his uncle. Roger made his higher studies at Oxford and Paris, and was later professor at Oxford (Franciscan school). He was greatly influenced by his Oxonian masters and friends Richard Fitzacre and Edmund Rich, but especially by Robert Grosseteste and Adam Marsh, both professors at the Franciscan school, and at Paris by the Franciscan Petrus Peregrinus de Maricourt (see Schlund in "Archiv. Francisc. Histor.", IV, 1911, pp. 436 sqq.) They created in him a predilection for positive sciences, languages, and physics; and to the last-mentioned he owed his entrance about 1240 (1251? 1257?) into the Franciscans, either at Oxford or Paris. He continued his learned work; illness, however, compelled him to give it up for two years. When he was able to recommence his studies, his superiors imposed other duties on him, and forbade him to publish any work out of the order without special permission from the higher superiors "under pain of losing the book and of fasting several days with only bread and water."

This prohibition has induced modern writers to pass severe judgment upon Roger's superiors being jealous of Roger's abilities; even serious scholars say they can hardly understand how Bacon conceived the idea of joining the Franciscan Order. Such critics forget that when Bacon entered the order the Franciscans numbered many men of ability in no way inferior to the most famous scholars of other religious orders (see Felder, "Gesch. der wissenschaftlichen Studien im Franziskanerorden bis um die Mitte des 13. Jahrhunderts", Freiburg, 1904). The prohibition enjoined on Bacon was a general one, which extended to the whole order; its promulgation was not even directed against him, but rather against Gerard of Borgo San Donnino, as Salimbene says expressly (see "Chronica Fr. Salimbene Parmensis" in "Mon. Germ. Hist." SS.", XXII, 462, ed. Holder-Egger). Gerard had published in 1254 without permission his heretical work, "Introductorius in Evangelium æternum"; thereupon the General Chapter of Narbonne in 1260 promulgated the above-mentioned decree, identical with the "constitutio gravis in contrarium" Bacon speaks of, as the text shows (see the constitution published by Ehrle, S.J., "Die ältesten Redactionen der Generalconstitutionen des Franziskanerordens" in "Archiv für Literatur- und Kirchengeschichte des Mittelalters", VI, 110; St. Bonaventure, "Opera Omnia", Quaracchi, VIII, 456).

We need not wonder then that Roger's immediate superiors put the prohibition into execution, especially as Bacon was not always very correct in doctrine; and although on the one hand it is wrong to consider him as a necromancer and astrologer, an enemy of scholastic philosophy, an author full of heresies and suspected views, still we cannot deny that some of his expressions are imprudent and inaccurate. The judgments he passes on other scholars of his day are sometimes too hard, so it is not surprising that his friends were few. The above-mentioned prohibition was rescinded in Roger's favour unexpectedly in 1266. Some years before, while still at Oxford, he had made the acquaintance of Cardinal Guy le Gros de Foulques, whom Urban IV had sent to England to settle the disputes between Henry III and the barons; others believe that the cardinal met Roger at Paris, in 1257 or 1258 (see "Archiv. Francisc. Histor.", IV, 442). After a conference about some current abuses, especially about ecclesiastical studies, the cardinal asked Roger to present his idea in writing. Roger delayed in doing this; when the Cardinal became Clement IV and reiterated his desire, Bacon excused himself because the prohibition of his superiors stood in the way. Then the pope in a letter from Viterbo (22 June, 1266) commanded him to send his work immediately, notwithstanding the prohibition of superiors or any general constitution whatsoever, but to keep the commission a secret (see letter published by Martene-Durand, "Thesaurus novus anecdotorum", II, Paris, 1717, 358, Clement IV, epp. n. 317 a; Wadding, "Annales", ad an. 1266, n. 14, II, 294; IV, 265; Sbaralea, "Bullarium Franciscanum", III, 89 n. 8f, 22 June, 1266).

We may suppose that the pope, as Bacon says, from the first had wished the matter kept secret; otherwise we can hardly understand why Bacon did not get permission of his superiors; for the prohibition of Narbonne was not absolute; it only forbade him to publish works outside the order "unless they were examined thoroughly by the minister general or by the provincial together with his definitors in the provincial chapter". The removal of the prohibitive constitution did not at once remove all the obstacles; the secrecy of the matter rather produced new embarrassments, as Bacon frankly declares. The first impediment was the contrary will of his superiors: "as your Holiness", he writes to the pope, "did not write to them to excuse me, and I could not make known to them Your secret, because You had commanded me to keep the matter a secret, they did not let me alone but charged me with other labours; but it was impossible for me to obey because of Your commandment". Another difficulty was the lack of money necessary to obtain parchment and to pay copyists. As the superiors knew nothing of his commission, Bacon had to devise means to obtain money. Accordingly, he ingenuously reminded the pope of this oversight, "As a monk", he says, "I for myself have no money and cannot have; therefore I cannot borrow, not having wherewith to return; my parents who before were rich, now in the troubles of war have run into poverty; others, who were able refused to spend money; so deeply embarrassed, I urged my friends and poor people to expend all they had, to sell and to pawn their goods, and I could not help promising them to write to You and induce Your Holiness to fully reimburse the sum spent by them (60 pounds)" ("Opus Tertium", III, p. 16).

Finally, Bacon was able to execute the pope's desire; in the beginning of 1267 he sent by his pupil John of Paris (London?) the "Opus Majus", where he puts together in general lines all his leading ideas and proposals; the same friend was instructed to present to the pope a burning-mirror and several drawings of Bacon appertaining to physics, and to give all explanations required by His Holiness. The same year (1267) he finished his "Opus Minus", a recapitulation of the main thoughts of the "Opus Majus", to facilitate the pope's reading or to submit to him an epitome of the first work if it should be lost. With the same object, and because in the first two works some ideas were but hastily treated, he was induced to compose a third work, the "Opus Tertium"; in this, sent to the pope before his death (1268), he treats in a still more extensive manner the whole material he had spoken of in his preceding works. Unfortunately his friend Clement IV died too soon, without having been able to put into practice the counsels given by Bacon. About the rest of Roger's life we are not well informed. The "Chronica XXIV Generalium Ordinis Minorum" says that "the Minister General Jerome of Ascoli [afterwards Pope Nicholas IV] on the advice of many brethren condemned and rejected the doctrine of the English brother Roger Bacon, Doctor of Divinity, which contains many suspect innovations, by reason of which Roger was imprisoned" (see the "Chronica" printed in "Analecta Franciscana", III, 360). The assertion of modern writers, that Bacon was imprisoned fourteen or fifteen years, although he had proved his orthodoxy by the work "De nullitate magiæ", has no foundation in ancient sources.

Some authors connect the fact of imprisonment related in the "Chronica" with the proscription of 219 theses by Stephen Tempier, Bishop of Paris, which took place 7 March, 1277 (Denifle, "Chartularium Universitatis Pariensis", I, 543, 560). Indeed it was not very difficult to find some "suspect innovation" in Bacon's writings, especially with regard to the physical sciences. As F. Mandonnet, O.P., proves, one of his incriminated books or pamphlets was his "Speculum Astronomiæ", written in 1277, hitherto falsely ascribed to Blessed Albert the Great [Opera Omnia, ed. Vives, Paris, X, 629 sq.; cf. Mandonnet, "Roger Bacon et le Speculum Astronomiæ (1277) in "Revue Néo-Scolastique", XVII, Louvain, 1910, 313-35]. Such and other questions are not yet ripe for judgment; but it is to be hoped that the newly awakened interest in Baconian studies and investigations will clear up more and more what is still obscure in Roger's life.

The writings attributed to Bacon by some authors amount to about eighty; many (e.g. "Epistola de magnete", composed by Petrus Peregrinus de Maricourt) are spurious, while many are only treatises republished separately under new titles. Other writings or parts of writings certainly composed by him were put in circulation under the name of other scholars, and his claim to their authorship can be established only from internal reasons of style and doctrine. Other treatises still lie in the dust of the great European libraries, especially of England, France, and Italy. Much remains to be done before we can expect an edition of the "Opera Omnia" of Roger Bacon. For the present the following statements may suffice. Before Bacon entered the order he had written many essays and treatises on the subjects he taught in the school, for his pupils only, or for friends who had requested him to do so, as he confesses in his letter of dedication of the "Opus Majus" sent to the pope: "Multa in alio statu conscripseram propter juvenum rudimenta" (the letter was discovered in the Vatican Library by Abbot Gasquet, O.S.B., and first published by him in the "English Historical Review", 1897, under the title "An unpublished fragment of a work by Roger Bacon", 494 sq.; for the words above cited, see p. 500). To this period seem to belong some commentaries on the writings of Aristotle and perhaps the little treatise "De mirabili potestate artis et naturæ et de nullitate magiæ" (Paris, 1542; Oxford, 1604; London, 1859). The same work was printed under the title "Epistola de secretis operibus artis et naturæ" (Hamburg, 1608, 1618). After joining the order, or more exactly from about the years 1256-57, he did not compose works of any great importance or extent, but only occasional essays requested by friends, as he says in the above-mentioned letter, "now about this science, now about another one", and only more transitorio (see "Eng. Hist. Rev.", 1897, 500). In the earlier part of his life he probably composed also "De termino pascali" (see letter of Clement IV in "Bull. Franc.", III, 89); for it is cited in another work, "Computus naturalium", assigned to 1263 by Charles ("Roger Bacon. Sa vie, etc.", Paris, 1861, p. 78; cf. pp. 334 sqq.).

The most important of all his writings are the "Opus Majus", the "Opus Minus", and the "Tertium". The "Opus Majus" deals in seven parts with (1) the obstacles to real wisdom and truth, viz. errors and their sources; (2) the relation between theology and philosophy, taken in its widest sense as comprising all sciences not strictly philosophical: here he proves that all sciences are founded on the sacred sciences, especially on Holy Scripture; (3) the necessity of studying zealously the Biblical languages, as without them it is impossible to bring out the treasure hidden in Holy Writ; (4) mathematics and their relation and application to the sacred sciences, particularly Holy Scripture; here he seizes an opportunity to speak of Biblical geography and of astronomy (if these parts really belong to the "Opus Majus"); (5) optics or perspective; (6) the experimental sciences; (7) moral philosophy or ethics. The "Opus Majus" was first edited by Samuel Jebb, London, 1733, afterwards at Venice, 1750, by the Franciscan Fathers. As both editions were incomplete, it was edited recently by J. H. Bridges, Oxford, 1900 (The 'Opus Majus' of Roger Bacon, edited with introduction and analytical table," in 2 vols.); the first three parts of it were republished the same year by this author in a supplementary volume, containing a more correct and revised text. It is to be regretted that this edition is not so critical and accurate as it might have been. As already noted, Bacon's letter of dedication to the pope was found and published first by Dom Gasquet; indeed the dedication and introduction is wanting in the hitherto extant editions of the "Opus Majus", whereas the "Opus Minus" and "Opus Tertium" are accompanied with a preface by Bacon (see "Acta Ord. Min.", Quaracchi, 1898, where the letter is reprinted).

Of the "Opus Minus", the relation of which to the "Opus Majus" has been mentioned, much has been lost. Originally it had nine parts, one of which must have been a treatise on alchemy, both speculative and practical; there was another entitled "The seven sins in the study of theology". All fragments hitherto found have been published by J. S. Brewer, "Fr. R. Bacon opp. quædam hactenus inedita", vol. I (the only one) containing: (1) "Opus Tertium"; (2) "Opus Minus"; (3) "Compendium Philos." The appendix adds "De secretis artis et naturæ operibus et de nullitate magiæ", London, 1859 (Rerum Britann. med. æv. Script.). The aim of the "Opus Tertium" is clearly pointed out by Bacon himself: "As these reasons [profoundness of truth and its difficulty] have induced me to compose the Second Writing as a complement facilitating the understanding of the First Work, so on account of them I have written this Third Work to give understanding and completeness to both works; for many things are here added for the sake of wisdom which are not found in the other writings ("Opus Tertium", I, ed. Brewer, 6). Consequently this work must be considered, in the author's own opinion, as the most perfect of all the compositions sent to the pope; therefore it is a real misfortune that half of it is lost. The parts we possess contain many autobiographical items. All parts known in 1859 were published by Brewer (see above). One fragment dealing with natural sciences and moral philosophy has been edited for the first time by Duhem ("Un fragment inédit de l'Opus Tertium de Roger Bacon précédé d'une étude sur ce fragment", Quaracchi, 1909); another (Quarta pars communium naturalis philos.) by Höver (Commer's "Jahrb. für Philos. u. speculative Theol.", XXV, 1911, pp. 277-320). Bacon often speaks of his "Scriptum principale". Was this a work quite different from the others we know? In many texts the expression only means the "Opus Majus", as becomes evident by its antithesis to the "Opus Minus" and "Opus Tertium". But there are some other sentences where the expression seems to denote a work quite different from the three just mentioned, viz. one which Bacon had the intention of writing and for which these works as well as his proeambula were only the preparation.

If we may conclude from some of his expressions we can reconstruct the plan of this grand encyclopædia: it was conceived as comprising four volumes, the first of which was to deal with grammar (of the several languages he speaks of) and logic; the second with mathematics (arithmetic and geometry), astronomy, and music; the third with natural sciences, perspective, astrology, the laws of gravity, alchemy, agriculture, medicine, and the experimental sciences; the fourth with metaphysics and moral philosophy (see Delorme in "Dict. de Theol.", s. v. Bacon, Roger; Brewer, pp. 1 sq.; Charles, 370 sq., and particularly Bridges, I, xliii sq.). It is even possible that some treatises, the connection of which with the three works ("Opus Majus", "Opus Minus", "Opus Tertium") or others is not evident, were parts of the "Scriptum principale"; see Bridges, II, 405 sq., to which is added "Tractatus Fr. Rogeri Bacon de multiplicatione specierum", which seems to have belonged originally to a work of greater extent. Here may be mentioned some writings hitherto unknown, now for the first time published by Robert Steele: "Opera hactenus inedita Rogeri Baconi. Fasc. I: Metaphysica Fratris Rogeri ordinis fratrum minorum. De viciis contractis in studio theologiæ, omnia quæ supersunt nunc primum edidit R. St.", London, 1905; Fasc. II: Liber primus communium naturalium Fratris Rogeri, partes I et II", Oxford, 1909. Another writing of Bacon, "Compendium studii philosophiæ", was composed during the pontificate of Gregory X who succeeded Clement IV (1271-76), as Bacon speaks of this last-named pope as the "predecessor istius Papæ" (chap. iii). It has been published, as far as it is extant, by Brewer in the above-mentioned work. He repeats there the ideas already touched upon in his former works, as for instance the causes of human ignorance, necessity of learning foreign languages, especially Hebrew, Arabic, and Greek; as a specimen are given the elements of Greek grammar.

About the same time (1277) Bacon wrote the fatal "Speculum Astronomiæ" mentioned above. And two years before his death he composed his "compendium studii theologiæ" (in our days published for the first time in "British Society of Franciscan Studies", III, Aberdeen, 1911), where he set forth as in a last scientific confession of faith the ideas and principles which had animated him during his long life; he had nothing to revoke, nothing to change. Other works and pamphlets cannot be attributed with certainty to any definite period of his life. To this category belong the "Epistola de laude Scripturarum", published in part by Henry Wharton in the appendix (auctarium) of "Jacobi Usserii Armachani Historia Dogmatica de Scripturis et sacris vernaculis" (London, 1689), 420 sq. In addition there is both a Greek and a Hebrew grammar, the last of which is known only in some fragments: "The Greek grammar of Roger Bacon and a fragment of his Hebrew Grammar, edited from the MSS., with an introduction and notes", Cambridge, 1902. Some specimens of the Greek Grammar, as preserved in a MS. of Corpus Christi College, Oxford, had been published two years before by J. L. Heiberg in "Byzantinische Zeitschrift", IX, 1900, 479-91. The above-mentioned edition of the two grammars cannot be considered very critical (see the severe criticism by Heiberg, ibid., XII, 1903, 343-47). Here we may add Bacon's "Speculum Alchemiæ", Nuremberg, 1614 (Libellus do alchimia cui titulus: Spec. Alchem.); it was translated into French by Jacques Girard de Tournus, under the title "Miroir d'alquimie", Lyons, 1557. Some treatises dealing with chemistry were printed in 1620 together in one volume containing: (1) "Breve Breviarium de dono Dei"; (2) "Verbum abbreviatum de Leone viridi"; (3) "Secretum secretorum naturæ de laude lapidis philosophorum"; (4) "Tractatus trium verborum"; (5) "Alchimia major". But it is possible that some of these and several other treatises attributed to Bacon are parts of works already mentioned, as are essays "De situ orbis", "De regionibus mundi", "De situ Palæstinæ", "De locis sacris", "Descriptiones locorum mundi", "Summa grammaticalis" (see Golubovich, "Biblioteca bio-bibliografica della Terra Santa e dell'Oriente Francescano", Quaracchi, 1906, I, 268 sq.).

If we now examine Bacon's scientific systems and leading principles, his aims and his hobby, so to say, we find that the burden not only of the writings sent to the pope, but also of all his writings was: ecclesiastical study must be reformed. All his ideas and principles must be considered in the light of this thesis. He openly exposes the "sins" of his time in the study of theology, which are seven, as he had proved, in the "Opus Majus". Though this part has been lost, we can reconstruct his arrangement with the aid of the "Opus Minus" and "Opus Tertium". The first sin is the preponderance of (speculative) philosophy. Theology is a Divine science, hence it must be based on Divine principles and treat questions touching Divinity, and not exhaust itself in philosophical cavils and distinctions. The second sin is ignorance of the sciences most suitable and necessary to theologians; they study only Latin grammar, logic, natural philosophy (very superficially!) and a part of metaphysics: four sciences very unimportant, scientiæ viles. Other sciences more necessary, foreign (Oriental) languages, mathematics, alchemy, chemistry, physics, experimental sciences, and moral philosophy, they neglect. A third sin is the defective knowledge of even the four sciences which they cultivate: their ideas are full of errors and misconceptions, because they have no means to get at the real understanding of the authors from whom they draw all their knowledge, since their writings abound in Greek, Hebrew, and Arabic expressions. Even the greatest and most highly-esteemed theologians show in their works to what an extent the evil has spread.

Another sin is the preference for the "Liber Sententiarum" and the disregard of other theological matters, especially Holy Scriptures; he complains: "The one who explains the 'Book of the Sentences' is honoured by all, whereas the lector of Holy Scripture is neglected; for to the expounder of the Sentences there is granted a commodious hour for lecturing at his own will, and if he belongs to an order, a companion and a special room; whilst the lector of Holy Scripture is denied all this and must beg the hour for his lecture to be given at the pleasure of the expounder of the Sentences. Elsewhere the lector of the Sentences holds disputations and is called master, whereas the lector of the [Biblical] test is not allowed to dispute" ("Opus Minus", ed. Brewer, 328 sq.). Such a method, he continues, is inexplicable and very injurious to the Sacred Text which contains the word of God, and the exposition of which would offer many occasions to speak about matters now treated in the several "Summæ Sententiarum". Still more disastrous is the fifth sin: the text of Holy Writ is horribly corrupted, especially in the "exemplar Parisiense", that is to say the Biblical text used at the University of Paris and spread by its students over the whole world. Confusion has been increased by many scholars or religious orders, who in their endeavours to correct the Sacred Text, in default of a sound method, have in reality only augmented the divergences; as every one presumes to change anything "he does not understand, a thing he would not dare to do with the books of the classical poets", the world is full of "correctors or rather corruptors". The worst of all sins is the consequence of the foregoing: the falsity or doubtfulness of the literal sense (sensus litteralis ) and consequently of the spiritual meaning (sensus spiritualis ); for when the literal sense is wrong, the spiritual sense cannot be right, since it is necessarily based upon the literal sense. The reasons of this false exposition are the corruption of the sacred text and ignorance of the Biblical languages. For how can they get the real meaning of Holy Writ without this knowledge, as the Latin versions are full of Greek and Hebrew idioms?

The seventh sin is the radically false method of preaching: instead of breaking to the faithful the Bread of Life by expounding the commandments of God and inculcating their duties, the preachers content themselves with divisions of the arbor Porphyriana, with the jingle of words and quibbles. They are even ignorant of the rules of eloquence, and often prelates who during their course of study were not instructed in preaching, when obliged to speak in church, beg the copy-books of the younger men, which are full of bombast and ridiculous divisions, serving only to "stimulate the hearers to all curiosity of mind, but do not elevate the affection towards good" ("Opus Tertium", Brewer, 309 sq.). Exceptions are very few, as for instance Friar Bertholdus Alemannus (Ratisbon) who alone has more effect than all the friars of both orders combined (Friars Minor and Preachers). Eloquence ought to be accompanied by science, and science by eloquence; for "science without eloquence is like a sharp sword in the hands of a paralytic, whilst eloquence without science is a sharp sword in the hands of a furious man" ("Sapientia sine eloquentia est quasi gladius acutus in manu paralytici, sicut eloquentia expers sapientiæ est quasi gladius acutus in manu furiosi"; "Opus Tertium, I, Brewer, 4). But far from being an idle fault-finder who only demolished without being able to build up, Bacon makes proposals extremely fit and efficacious, the only failure of which was that they were never put into general practice, by reason of the premature death of the pope. Bacon himself and his pupils, such as John of Paris, whom he praises highly, William of Mara, Gerard Huy, and others are a striking argument that his proposals were no Utopian fancies: they showed in their own persons what in their idea a theologian should be. First of all, if one wishes to get wisdom, he must take care not to fall into the four errors which usually prevent even learned men from attaining the summit of wisdom, viz. "the example of weak and unreliable authority, continuance of custom, regard to the opinion of the unlearned, and concealing one's own ignorance, together with the exhibition of apparent wisdom" ("Fragilis et indignæ autoritatis exemplum, consuetudinis diuturnitas, vulgi sensus imperiti, et propriæ ignorantiæ occultatio cum ostentatione sapientiæ apparentis"; "Opus Majus", I, Bridges, 1, 2).

Thus having eliminated "the four general causes of all human ignorance", one must be convinced that all science has its source in revelation both oral and written. Holy Scripture especially is an inexhaustible fountain of truth from which all human philosophers, even the heathen, drew their knowledge, immediately or mediately; therefore no science, whether profane or sacred, can be true if contrary to Holy Writ (see "English Hist. Rev.", 1897, 508 sq.; "Opus Tertium", XXIV, Brewer, 87 sq.). This conviction having taken root, we must consider the means of attaining wisdom. Among those which lead to the summit are to be mentioned in the first place the languages, Latin, Greek, Hebrew, and Arabic. Latin does not suffice, as there are many useful works written in other languages and not yet translated, or badly translated, into Latin. Even in the best versions of scientific works, as for instance of Greek and Arabic philosophers, or of the Scriptures, as also in the Liturgy, there are still some foreign expressions retained purposely or by necessity, it being impossible to express in Latin all nuances of foreign texts. It would be very interesting to review all the other reasons adduced by Bacon proving the advantage or even necessity of foreign languages for ecclesiastical, social, and political purposes, or to follow his investigations into the physiological conditions of language or into what might have been the original one spoken by man. He distinguishes three degrees of linguistic knowledge; theologians are not obliged to reach the second degree, which would enable them to translate a foreign text into their own language, or the third one which is still more difficult of attainment and which would enable them to speak this language as their own. Nevertheless the difficulties of reaching even the highest degree are not as insurmountable as is commonly supposed; it depends only on the method followed by the master, and as there are very few scholars who follow a sound method, it is not to be wondered at that perfect knowledge of foreign languages is so rarely found among theologians (see "Opus Tertium", XX, Brewer, 64 sq.; "Compendium Studii phil.", VI, Brewer, 433 sq.). On this point, and in general of Roger's attitude towards Biblical studies, see the present author's article "De Fr. Roger Bacon ejusque sententia de rebus biblicis" in "Archivum Franciscanum Historicum", III, Quaracchi, 1910, 3-22; 185-213.

Besides the languages there are other means, e.g., mathematics, optics, the experimental sciences, and moral philosophy, the study of which is absolutely necessary for every priest, as Bacon shows at length. He takes special pains in applying these sciences to Holy Scripture and the dogmas of faith. These are pages so wonderful and evincing by their train of thought and the drawings inserted here and there such a knowledge of the subject matter, that we can easily understand modern scholars saying that Bacon was born out of due time, or, with regard to the asserted imprisonment, that he belonged to that class of men who were crushed by the wheel of their time as they endeavoured to set it going more quickly. It is in these treatises (and other works of the same kind) that Bacon speaks of the reflection of light, mirages, and burning- mirrors, of the diameters of the celestial bodies and their distances from one another, of their conjunction and eclipses; that he explains the laws of ebb and flow, proves the Julian calendar to be wrong; he explains the composition and effects of gunpowder, discusses and affirms the possibility of steam- vessels and aerostats, of microscopes and telescopes, and some other inventions made many centuries later. Subsequent ages have done him more justice in recognizing his merits in the field of natural science. John Dee, for instance, who addressed (1582) a memorial on the reformation of the calendar to Queen Elizabeth, speaking of those who had advocated this change, says: "None hath done it more earnestly, neither with better reason and skill, than hath a subject of this British Sceptre Royal done, named as some think David Dee of Radik, but otherwise and most commonly (upon his name altered at the alteration of state into friarly profession) called Roger Bacon: who at large wrote thereof divers treatises and discourses to Pope Clement the Fifth [sic ] about the year of our Lord, 1267. To whom he wrote and sent also great volumes exquisitely compiled of all sciences and singularities, philosophical and mathematical, as they might be available to the state of Christ his Catholic Church". Dee then remarks that Paul of Middleburg, in "Paulina de recta Paschæ celebratione", had made great use of Bacon's work: "His great volume is more than half thereof written (though not acknowledged) by such order and method generally and particularly as our Roger Bacon laid out for the handling of the matter" (cited by Bridges, "Opus Majus", I, p. xxxiv).

Longer time was needed before Bacon's merits in the field of theological and philosophical sciences were acknowledged. Nowadays it is impossible to speak or write about the methods and course of lectures in ecclesiastical schools of the Middle Ages, or on the efforts of revision and correction of the Latin Bible made before the Council of Trent, or on the study of Oriental languages urged by some scholars before the Council of Vienne, without referring to the efforts made by Bacon. In our own day, more thoroughly than at the Council of Trent, measures are taken in accordance with Bacon's demand that the further corruption of the Latin text of Holy Scripture should be prevented by the pope's authority, and that the most scientific method should be applied to the restoration of St. Jerome's version of the Vulgate. Much may be accomplished even now by applying Bacon's principles, viz.: (1) unity of action under authority; (2) a thorough consultation of the most ancient manuscripts; (3) the study of Hebrew and Greek to help where the best Latin manuscripts left room for doubt; (4) a thorough knowledge of Latin grammar and construction; (5) great care in distinguishing between St. Jerome's readings and those of the more ancient version (see "Opus Tertium", XXV, Brewer, 93 sq.; Gasquet, "English Biblical Criticism in the Thirteenth Century" in "The Dublin Review", CXX, 1898, 15). But there are still some prejudices among learned men, especially with regard to Bacon's orthodoxy and his attitude towards Scholastic philosophy. It is true that he speaks in terms not very flattering of the Scholastics, and even of their leaders. His style is not the ordinary Scholastic style proceeding by inductions and syllogisms in the strictest form; he speaks and writes fluently, clearly expressing his thoughts as a modern scholar treating the same subject might write. But no one who studies his works can deny that Bacon was thoroughly trained in Scholastic philosophy. Like the other Scholastics, he esteems Aristotle highly, while blaming the defective Latin versions of his works and some of his views on natural philosophy. Bacon is familiar with the subjects under discussion, and it may be of interest to note that in many cases he agrees with Duns Scotus against other Scholastics, particularly regarding matter and form and the intellectus agens which he proves not to be distinct substantially from the intellectus possibilis ("Opus Majus", II, V; "Opus Tertium", XXIII).

It would be difficult to find any other scholar who shows such a profound knowledge of the Arabic philosophers as Bacon does. Here appears the aim of his philosophical works, to make Christian philosophy acquainted with the Arabic philosophers. He is an enemy only of the extravagances of Scholasticism, the subtleties and fruitless quarrels, to the neglect of matters much more useful or necessary and the exaltation of philosophy over theology. Far from being hostile to true philosophy, he bestows a lavish praise on it. None could delineate more clearly and convincingly than he, what ought to be the relation between theology and philosophy, what profit they yield and what services they render to each other, how true philosophy is the best apology of Christian faith (see especially "Opus Majus", II and VII; "Compend. studii philos."). Bacon is sometimes not very correct in his expressions; there may even be some ideas that are dangerous or open to suspicion (e.g. his conviction that a real influence upon the human mind and liberty and on human fate is exerted by the celestial bodies etc.). But there is no real error in matters of faith, and Bacon repeatedly asks the reader not to confound his physics with divination, his chemistry with alchemy, his astronomy with astrology; and certainly he submitted with all willingness his writings to the judgment of the Church. It is moving to note the reverence he displayed for the pope. Likewise he shows always the highest veneration towards the Fathers of the Church; and whilst his criticism often becomes violent when he blames the most eminent of his contemporaries, he never speaks or writes any word of disregard of the Fathers or ancient Doctors of the Church, even when not approving their opinion; he esteemed them highly and had acquired such a knowledge of their writings that he was no way surpassed by any of his great rivals. Bacon was a faithful scholar of open character who frankly uttered what he thought, who was not afraid to blame whatsoever and whomsoever he believed to deserve censure, a scholar who was in advance of his age by centuries. His iron will surmounted all difficulties and enabled him to acquire a knowledge so far surpassing the average science of his age, that he must be reckoned among the most eminent scholars of all times.

Of the vast Baconian bibliography we can mention only the most important books and articles in so far as we have made use of them. Besides those already cited we must mention: BALÆUS, Script. illustr. maiorus Brytann. Catalogus (Basle, 1577); Anecdota Oxon. Index Britannicæ SS. quos... collegit Joan. Balæus, ed. POOLE AND BATESON (OXFORD, 1902——); WOOD, Hist. et antiq. Univers. Oxon., I (Oxford, 1674); IDEM, Athenæ Oxon. (London, 1721), new ed. by BLISS (4 vols., London, 1813-20); WHARTON, Anglia sacra (London, 1691); HODY, De Bibliorum text. original., versionibus græc. et latina Vulgata, III (Oxford, 1705); LELANDUS, Comment. de Scriptor. Brittanicis, ed. HALL (Oxford, 1709); OUDIN, Comment. de Script. Ecclesiæ antiq., I (Frankfort, 1722), II-III (Leipzig, 1722); WADDING-FONSECA, Annales Ord. Min., IV-V; WADDING, Scriptores O. M. (Rome, 1650, 1806, 1906); TANNER, Bibl. Britann.-Hibern. (London, 1748); SBARALEA, Supplement. ad SS. O. M. (Rome, 1806); BERGER, De l'hist. de la Vulgate en France (Paris, 1887); IDEM, Quam notitiam linguæ hebr. habuerunt christiani med. ævi (Paris, 1893); cf. the criticism of this book by SOURY in Bibl. de l'Ecole des Chartes, LIV (1893), 733-38; DENIFLE, Die Handschr. der Bibel-Corrector. des 13. Jahrh. in Archiv f. Lit.- u. Kirchengesch. des Mittelalters, IV, 263 sqq.; 471 sqq.; DÖRING, Die beiden Bacon in Archiv f. Gesch. d. Philos., XVII, (1904), 3 sqq.; FERET, Les emprisonnements de R. Bacon in Revue des quest. histor., L (1891), 119-42; IDEM, La faculté de théol. de Paris (4 vols., Paris, 1894-96); FLÜGEL, R. Bacons Stellung in d. Gesch. d. Philologie in Philos. Studien, XIX (1902), 164 sqq.; HEITZ, Essai histor. sur les rapports entre la philos. et la foi, de Bérenger de Tours à St. Thomas (Paris, 1909), 117 sqq.; HIRSCH, Early English Hebraists: R. Bacon and his Predecessors in The Jewish Quarterly Review (Oct., 1890), reprinted in IDEM, A Book of Essays (London, 1905), 1-72; Hist. de la France, XX (Paris, 1842), 227 sqq.; HOFFMANS, La synthèse doctrinale de R. B. in Archiv f. Gesch. d. Philos. (Berne, 1907); IDEM, L'intuition mystique de la science in Revue Néo-Scholastuque (1909), 370 sqq. (cf. 1906, 371 sqq.; 1908, 474 sqq.; 1909, 33 sqq.); JARRETT, A Thirteenth-Century Revision Committee of the Bible in Irish Theological Quarterly, IV (Maynooth, 1910), 56 sqq.; JOURDAIN, Discussion de quelques points de la biogr. de R. B. in Comptes rendus Acad. Inscr. et Belles-Lettres, I (1873), 309 sqq.; KREMBS, R. B.'s Optik in Natur u. Offenbarung (1900); LANGEN, R. Bacon in Histor. Zeitschr., LI (1883), 434-50; MARTIN, La Vulgate latine au XIIIe siècle d'après R. B. (Paris, 1888); Mon. Germ. Hist.: SS., XXVIII, 569 sqq.; NARBEY, Le moine R. B. et le mouvement scientifque au XIIIe siècle in Revue des quest. histor., XXXV (1894), 115 sqq.; PARROT, R. B., sa personne, son génie, etc. (Paris, 1894); PESCH, De inspiratione S. Scripturæ (Freiburg, 1906), 163 sq.; PICAVET, Les éditions de R. B. in Journal des Savants (1905), 362-69; IDEM, Deux directions de la théol. et de l'exégèse au XIIIe siècle. Thomas et Bacon in Revue de l'hist. des religions (1905), 172, or printed separately (Paris, 1905); POHL, Das Verhältnis der Philos. zur Theol. bei R. B. (Neustrelitz, 1893); SAISSET, R. B., sa vie et son oeuvre in Revue des deux mondes, XXXIV, (1861), 361-91; IDEM, Précurseurs et disciples de Descartes (Paris, 1862); SALEMBIER, Une page inédite de l'hist. de la Vulgate (Amiens, 1890); SCHNEIDER, R. B., eine Monographie als Beitrag zur Gesch der Philos. des 13. Jahr. aus den Quellen (Augsburg, 1873); SIEBERT, R. B., sein Leben u. seine Philos. (Marburg, 1861); STARHAHN, Das opus maius des R. B. nach seinem Inhalt u. seiner Bebeutung f. d. Wissenschaft betrachtet in Kirchl. Monatsschr., XII (1893), 276-86; STRUNZ, Gesch. der Naturwissenschaften im Mittelalter (Stuttgart, 1910), 93-99; UBALD, Franciscan England in the Past in Franciscan Annals, XXXIII (1908), 369-71; XXXIV, (1909), 11-14; VALDARNINI, Esperienza e ragionamento in R. B. (Rome, 1896); VERCELLONE, Dissertazioni accademiche di vario argumento (Rome, 1864); VOGL, Die Physik R. B.'s (Erlangen, 1906); WERNER, Kosmologie u. allgem. Naturlehre R. B.'s Psychol., Erkenntniss- u. Wissenschaftslehre des R. B. in Sitzungsber. der k. k. Akad. d. W., XCIII (Vienna), 467-576; XCIV, 489-612; WITHEFORD, Bacon as an Interpreter of Holy Scripture inExpositor (1897), 349-60; WULF, (DE), Hist. de la philos. médiévale (2nd ed., Louvain, 1905), 419-27.

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External links

• Hackett, Jeremiah. "Roger Bacon". In Zalta, Edward N. (ed.). Stanford Encyclopedia of Philosophy. ISSN 1095-5054. OCLC 429049174.
• "Roger Bacon" – In Our Time 2017
• Fieser, James; Dowden, Bradley (eds.). "Roger Bacon". Internet Encyclopedia of Philosophy. ISSN 2161-0002. OCLC 37741658.
• Fieser, James; Dowden, Bradley (eds.). "Roger Bacon on Language". Internet Encyclopedia of Philosophy. ISSN 2161-0002. OCLC 37741658.
• Herbermann, Charles, ed. (1913), "Roger Bacon", Catholic Encyclopedia, New York: Robert Appleton Company
• 1901–1906 Jewish Encyclopedia: Bacon, Roger
• Roger Bacon Quotes at Convergence
• Roger Bacon: On Experimental Science, 1268
• O'Connor, John J; Robertson, Edmund F., "Roger Bacon", MacTutor History of Mathematics Archive, University of St Andrews
• Brehm, Edmund A., "Roger Bacon's Place in the History of Alchemy"
• "Roger-Bacon". Britannica Encyclopedia. January 2024.
• classic wood engraving of Roger Bacon's visage, appears in Munson and Taylor's "Jane's History of Aviation" c.1972
• Works by Roger Bacon at LibriVox (public domain audiobooks)