Roger Bacon (1214–1292), UK – magnifying glass
Roger Bacon, O.F.M. (c. 1214–1294) (scholastic accolade Doctor Mirabilis, meaning "wonderful teacher"), was an English philosopher and Franciscan friar who placed considerable emphasis on the study of nature through empirical methods. He is sometimes credited, mainly starting in the 19th century, as one of the earliest European advocates of the modern scientific method inspired by Aristotle and later Arabic scholars, such as those of Muslim scientist Alhazen.[2] However, more recent reevaluations emphasize that he was essentially a medieval thinker, with much of his "experimental" knowledge obtained from books, in the scholastic tradition.[3] A survey of the reception of Bacon's work over centuries found it often reflects the concerns and controversies central to the receivers.[4]
Roger Bacon was born in Ilchester in Somerset, England, possibly in 1213 or 1214 at theIlchester Friary.[5] The only source for his birth date is his statement in the Opus Tertium, written in 1267, that "forty years have passed since I first learned the alphabet". The 1214 birth date assumes he meant 40 years had passed since he matriculated at Oxford at age 13. If he had been literal, his birth date was more likely around 1220 to 1222. In the same passage he said that for all but two of the forty years he had been engaged in study.[6] His family appears to have been well-off, but during the stormy reign of Henry III of Englandtheir property was seized and several family members driven into exile.
Bacon studied at Oxford and may have been a disciple of Grosseteste. He became a master at Oxford, lecturing on Aristotle. There is no evidence he was ever awarded a doctorate — the title Doctor Mirabilis was posthumous and figurative. Sometime between 1237 and 1245, he began lecturing at the University of Paris, then the centre of European intellectual life. Where he was between 1247 and 1256 is unknown, but about 1256 he became a friar in the Franciscan Order, and no longer held a teaching post. After 1260, his activities were restricted by a Franciscan statute prohibiting friars from publishing books or pamphlets without prior approval.[7]
Bacon circumvented this through his acquaintance with Cardinal Guy le Gros de Foulques, who became Pope Clement IV in 1265. Clement IV issued a mandate ordering Bacon to write to him concerning the place of philosophy within theology. Bacon sent the Pope his Opus Majus, which presented his views on how to incorporate the philosophy of Aristotle and science into a new Theology. Bacon also sent his Opus minus, De multiplicatione specierum, and possibly other works on alchemy and astrology.[8]
Pope Clement died in 1268 and Bacon lost his protector. Sometime between 1277 and 1279, Bacon was apparently imprisoned or placed under house arrest for unknown reasons. Sometime after 1278 Bacon returned to the Franciscan House at Oxford, where he continued his studies.[9] He is believed to have died in 1294.
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[hide]Changing interpretations of Bacon[edit]
In the 19th century it was a widely held interpretation that Bacon was a modern experimental scientist who emerged before his time. This reflected two prevalent views of the period: an emphasis upon experiment as the principal form of scientific activity and a general acceptance of the characterization of the Middle Ages as the "Dark Ages".[11][12] Some writers of the period carried this account further. For instance, according to Andrew Dickson White, Bacon was repeatedly persecuted and imprisoned because of the opposition of the medieval Church.[13][14] In this view, which is still reflected in some 21st-century popular science books,[15][16] Bacon would be an advocate of modern experimental science who somehow emerged as an isolated figure in an age supposed to be hostile toward scientific ideas.[17] He was also presented as a visionary; for instance, Frederick Mayer wrote that Bacon predicted the invention of the submarine, automobile, and airplane.[18]
However, in the course of the 20th century, the philosophical understanding of the role of experiment in the sciences was substantially modified. Starting with works of Pierre Duhem,Raoul Carton, and Lynn Thorndike,[19] Bacon's advocacy of scientia experimentalis has been argued to differ from modern experimental science.[20] New historical research has also shown that medieval Christians were not generally opposed to scientific investigation[21][22]and revealed the extent and variety of medieval science. In fact, many medieval sources of and influences on Bacon's scientific activity have been identified.[23] For instance, Bacon's idea that inductively derived conclusions should be submitted for further experimental testing is very much like Robert Grosseteste's 'Method of Verification',[24] and Bacon's work on optics and the calendar also followed the lines of inquiry of Grosseteste.[25]
As a result, the picture of Bacon has changed. One recent study summarized that: "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".[26] Bacon is thus seen as a leading, but not isolated, figure in the beginnings of medieval universities at Paris and Oxford, among other contemporary exponents of this shift in the philosophy of science (as we call it today), including Grosseteste (who preceded Bacon), William of Auvergne, Henry of Ghent, Albert Magnus, Thomas Aquinas, John Duns Scotus, andWilliam of Ockham.[27]
As to the alleged persecution, the first known reference to an imprisonment originates around 80 years after Bacon's death. It says the order was given by the head of the Franciscans because of unspecified "suspected novelties".[28][29] However, the fact that no earlier report has been found drives skepticism over the assertion. Moreover, current historians of science who see an incarceration as plausible typically do not connect it with Bacon's scientific writings.[29] Instead, if it happened, scholars speculate that his troubles resulted from such things as his sympathies for radical Franciscans,[30] attraction to contemporary prophecies,[29] or interest in certain astrological doctrines.[31] Bacon's personality has also been mentioned as a factor.[32]
A recent review of the many visions that each age has held about Roger Bacon says contemporary scholarship still neglects one of the most important aspects of his life and thought: the commitment to the Franciscan order. "His Opus maius 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."[4]
Works[edit]
Bacon's Opus Majus contains treatments of mathematics and optics, alchemy, and the positions and sizes of the celestial bodies.
View of the past[edit]
The training Bacon had received showed him the defects in existing academic debate.[citation needed] Aristotle was known only through translations, as none of the professors would learn Greek; the same was true of Scripture and many of the otherauctores ("authorities") referenced in traditional education. In contrast to Aristotle's argument that facts be collected before deducing scientific truths, physical science was not carried out by observations from the natural world, but by arguments based solely on tradition and prescribed authorities.
Bacon withdrew from the scholastic routine[citation needed] and devoted himself to languages and experimental research. The mathematicians whom he considered perfect were Peter of Maricourt and John of London, and two were good: Campanus of Novara and a Master Nicholas. Peter was the author of a famous letter to a friend, Epistola de Magnete, in which he described some of the earliest European experiments with magnetism.[33] Campanus wrote several important works on astronomy, astrology, and the calendar.[34] Bacon often mentioned his debt to the work of Robert Grosseteste and Adam Marsh, as well as to other lesser figures. He was clearly not an isolated scholar in the thirteenth century.[35]
New approach[edit]
In his writings, Bacon calls for a reform of theological study. Less emphasis should be placed on minor philosophical distinctions than had been the case in scholasticism. Instead, the Bible itself should return to the centre of attention and theologians should thoroughly study the languages in which their original sources were composed. He was fluent in several languages and lamented the corruption of the holy texts and the works of the Greek philosophers by numerous mistranslations and misinterpretations. Furthermore, he urged all theologians to study all sciences closely, and to add them to the normal university curriculum. With regard to the obtaining of knowledge, he strongly championed experimental study over reliance on authority, arguing that "thence cometh quiet to the mind". Bacon did not restrict this approach to theological studies. He rejected the blind following of prior authorities, both in theological and scientific study, which was the accepted method of undertaking study in his day.
In the Opus Minus he criticizes his contemporaries Alexander of Hales and Albertus Magnus, who, he says, had not studied the philosophy of Aristotle but only acquired their learning during their life as preachers.[36][37] Albert was received at Paris as an authority equal to Aristotle, Avicenna, and Averroes,[38] leading Bacon to proclaim that "never in the world [had] such monstrosity occurred before."[39]
Optics[edit]
The study of optics in part five of Opus Majus draws heavily on the works of both Claudius Ptolemy (his Optics in Arabic translation) and the Islamic scientists Alkindus (al-Kindi) and Alhazen (Ibn al-Haytham).[2][40] He includes a discussion of the physiology of eyesight, the anatomy of the eye and the brain, and considers light, distance, position, and size, direct vision, reflected vision, and refraction, mirrors and lenses. His research in optics was primarily oriented by the legacy of Alhazen through a Latin translation of the latter's monumental Kitab al-manazir (De aspectibus; Perspectivae; The Optics), while the impact of the tradition of al-Kindi (Alkindus) was principally mediated through the influence that this Muslim scholar had on the optics of Robert Grosseteste. Moreover, Bacon's investigations of the properties of the magnifying glass partly rested on the handed-down legacy of Islamic opticians, mainly Alhazen, who was in his turn influenced by Ibn Sahl's 10th-century legacy in dioptrics.[41]
Calendar[edit]
He was a forerunner in Calendar Reformation. Drawing on the recently discovered Greco-Muslim astronomy and on the calendaric writings of Robert Grosseteste, Bacon criticized the Julian calendar, describing it as intolerable, horrible and laughable. He had correctly deduced that the assumption of Julius Caesar's year of length of 365 days and a quarter was wrong. He proposed to correct its errors by deleting a day from the calendar every 125 or 130 years.[42] By not doing this correction, a surplus of time over the centuries had accumulated to nine days during his time.[43]
He proposed to Pope Clement IV in 1267 in his Opus Majus to rectify these errors by dropping a day every 125 years. He charged that the then notion of fixed equinoxes and solstices was also wrong.[43] As this is important in calculating the date of Easter, he was extremely distressed that Christians were celebrating Easter and other holy festivals on the wrong dates, because of this error. Unfortunately the untimely death of Pope Clement IV in 1268 put an end to his hopes.
Finally his fears were accepted and corrected only in 1582 by Pope Gregory XIII in the Gregorian Calendar reformation.
Other attributed works[edit]
In his own writings of 1260–1280 Bacon cited Secretum secretorum, which he attributed to Aristotle, far more than his contemporaries did. Often used as an argument for the special influence that this work had on Bacon's own is the manuscript of Secretum that Bacon edited, complete with his own introduction and notes, something Bacon seldom did with others' works. Although some early 20th century scholars like Robert Steele have pushed further along this path, arguing that Bacon's contact with the Secretum was a turning point in Bacon's philosophy, transforming him into an experimentalist, there is no clear reference to such a decisive impact of theSecretum in Bacon's own words. The dating of Bacon's edition of the Secretum is a key argument in this debate, but is still unresolved, with those arguing for a greater impact dating it earlier than those who urge caution in this interpretation.[44]
The cryptic Voynich manuscript has been attributed to Bacon by various sources, including by its first recorded owner, in a book drafted by William Romaine Newbold and posthumously edited and published by Roland Grubb Kent in 1928,[45] and in a 2005 book of Lawrence and Nancy Goldstone published by Doubleday and Broadway Books.[16][46] In strongly worded terms, historians of scienceLynn Thorndike[47] and George Sarton have dismissed these claims as unsupported.[48][49]
Another work of contentious date and even origin is the Epistola de Secretis Operibus Artis et Naturae, et de Nullitate Magiae (meaning Letter on the Secret Workings of Art and Nature, and on the Vanity of Magic), sometimes alternatively entitled De Mirabili Potestate Artis et Naturae (On the Wonderful Powers of Art and Nature).[50][51][52][53] This treatise dismisses magical practices likenecromancy,[52] and contains most of the alchemical work attributed to Bacon, chiefly a formula for philosopher's stone,[53] and perhaps one for gunpowder.[50] It also contains a number of passages about hypothetical flying machines and (what we today call) submarines, attributing their first use to Alexander the Great.[54]
Bacon is also the ascribed author of the alchemical manual Speculum Alchemiae, which was translated into English as The Mirror of Alchimy in 1597.[55] It is a short treatise about the composition and origin of metals, espousing "conventional" (with respect to the period) Arabian theories of mercury and sulfur as the constituents of metals, and containing vague allusions to transmutation. About this work, John Maxson Stillman wrote 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". M. M. Pattison Muir had a similar opinion, and Edmund Oscar von Lippmann considered this text a pseudepigraph.[56]
Gunpowder[edit]
Bacon is often considered the first European to describe a mixture containing the essential ingredients of gunpowder. Based on two passages from Bacon's Opus Maius and Opus Tertium, extensively analyzed by J. R. Partington, several scholars cited by Joseph Needham concluded that Bacon had most likely witnessed at least one demonstration of Chinese firecrackers, possibly obtained with the intermediation of other Franciscans, like his friend William of Rubruck, who had visited the Mongols.[50][57] 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."[50]
More controversial are the claims originating with Royal Artillery colonel Henry William Lovett Hime (at the beginning of the 20th century) that a cryptogram existed in Bacon's Epistola, giving the ratio of ingredients of the mixture. These were published, among other places, in the 1911 edition of Encyclopædia Britannica.[58] An early critic of this claim was Lynn Thorndike, starting with a letter in the 1915 edition of the journal Science,[59] and repeated in several books of his. M. M. Pattison Muir also expressed his doubts on Hime's theory, and they were echoed by John Maxson Stillman.[60] Robert Steele[61] and George Sarton also joined the critics.[62] Needham concurred with these earlier critics in their opinion that the additional passage does not originate with Bacon.[50] In any case, the proportions claimed to have been deciphered (7:5:5 saltpeter:charcoal:sulfur) are not even useful for stuffing firecrackers, burning slowly while producing mostly smoke, and failing to ignite inside a gun barrel.[63] The ~41% nitrate content is too low to have explosive properties.[64]
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