His linguistic work has been heralded for its early exposition of a universal grammar. However, more recent re-evaluations emphasise that Bacon was essentially a medieval thinker, with much of his "experimental" knowledge obtained from books in the scholastic tradition. Although gunpowder was first invented and described in China , Bacon was the first in Europe to record its formula. Roger Bacon was born in Ilchester in Somerset , England , in the early 13th century, although his date of birth is sometimes narrowed down to c.
Bacon studied at Oxford. There is no evidence he was ever awarded a doctorate. The title Doctor Mirabilis was posthumous and figurative. A caustic cleric named Roger Bacon is recorded speaking before the king at Oxford in In or at some point in the following decade, he accepted an invitation to teach at the University of Paris.
As a private scholar, his whereabouts for the next decade are uncertain  but he was likely in Oxford c. A passage in the Opus Tertium states that at some point he took a two-year break from his studies. Pope Urban IV absolved the king of his oath in 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 [n 3] and drove several members into exile.
In or , 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. By the mids, he was undertaking a search for patrons who could secure permission and funding for his return to Oxford. In or , 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.
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. Bacon also sent his Opus Minus , De Multiplicatione Specierum ,  De Speculis Comburentibus , an optical lens,  and possibly other works on alchemy and astrology.
Pope Clement died in and Bacon lost his protector. The Condemnations of 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 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. Sometime after , 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 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. Bacon's Greater Work , the Opus Maius , [n 5] contains treatments of mathematics , optics , alchemy , and astronomy , including theories on the positions and sizes of the celestial bodies.
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.
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. In Part I of the Opus Majus Bacon recognizes 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 and in especially high regard calling them "both philosophers and sacred writers" and defended the integration of Islamic philosophy into Christian learning.
Bacon charged that this meant the computation of Easter had shifted forward by 9 days since the First Council of Nicaea in The eventual Gregorian calendar drops one day from the first three centuries in each set of years. 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. 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.
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. 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. Bacon produced an edited edition complete with his own introduction and notes and his writings of the s and s 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. 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.
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. Passages in the Overview and the Greek grammar have been taken as an early exposition of a universal grammar underlying all human languages. 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.
The Mirror of Alchimy Speculum Alchemiae , a short treatise on the origin and composition of metals, is traditionally credited to Bacon. 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. Bacon was largely ignored by his contemporaries in favor 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.
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 , [n 10] 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 , 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.
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. As early as the 16th century, natural philosophers like 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 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 ". However, in the course of the 20th century, Husserl , Heidegger , and others emphasized the importance to 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.
Research also established that Bacon was not as isolated—and probably not as persecuted—as was once thought. Many medieval sources of and influences on Bacon's scientific activity have been identified. 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.
He was clearly not an isolated genius. As a result, the picture of Bacon has changed.
A form of gunpowder had been known in China since before AD , and as mentioned earlier Taylor, Mary K. Hermetism and Magic in Giordano Bruno. Overtaking Nature? Edelstein Fellow Reinhardt, C. 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. Eamon, "How to read a book of secrets", in Elaine Leong and Alisha Rankin eds , Secrets and knowledge in medicine and science, , pp.
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. 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 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 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. In Oxford lore, Bacon is credited as the namesake of Folly Bridge for having gotten himself placed under house arrest nearby.
To commemorate the th anniversary of Bacon's approximate year of birth, Prof. Erskine wrote the biographical play A Pageant of the Thirteenth Century , which was performed and published by Columbia University in Log in to post an annotation. If you don't have an account, then register here. Categories Map Family tree. Log in Register Search. Roger Bacon. Order of Friars Minor. Experientia designates the simple perception of singulars.
Only in a very loose sense can it be used of scientific knowledge. Sometimes, however, these two terms about experience are used interchangeably. In this account, Bacon has not yet come to his later notion of a scientia experimentalis , and the experimental verification certificatio of the conclusions of demonstrative knowledge ca.
He is dealing only with experience as the source of the principles of our knowledge of art and science. In other words, at this stage, Bacon is mainly concerned with Aristotle's definition of experience in the Metaphysics and Posterior Analytics , although one already notices that he relates the Aristotelian subject matter to the discussion in Alhacen's Perspectiva.
Nevertheless, it is also important to note that these Aristotelian concerns with Experimentum are repeated in at the beginning of Opus majus , Part Six on exprimental science, and thus, Aristotle's Metaphysics , Posterior Analytics and Meteorology together with the Optics of Ibn al-Haytham will form the necessary philosophical background for Bacon's later c. In the later post Communia naturalium , Bacon gives six meanings for the concept of matter.
Form has a certain priority to matter as the end of generation and as the perfection of the material principle. It is the principle of action and of knowledge. In general, for Bacon, matter is not a mere potency. It is an incomplete something substance and so for him matter and form are two incomplete substances that integrate to make one individual substance. In this one notices a notion of matter as in some sense a positive thing.
It is not a nullity. In both early and later works, Bacon objects to the idea that matter is one in number in all things. The background to this issue arises from Franciscan discussions at Paris on the nature of the unity of matter. Bacon holds that matter "is not numerically one, but in itself and from itself it is numerically distinct in numerically different beings. For example, matter as potentiality is the original source of the being of contingent things.
This is the non-being of the creature in contrast with the being of the Creator. Thus, Bacon will speak of the matter of both corporeal and spiritual beings, and hence of "spiritual matter," a concept that Aquinas found to be contradictory. In his later works, and specifically in his works on natural philosophy, Bacon presents nature as an active agent. The form or the species is the first effect of any natural agent.
The power of the species educes the emergence of the thing from the potency of matter. Matter has an active potency , and this is actualized due to the action of the natural external agent. Bacon has two distinct treatments of universals and individuation: his early works s and later in the Communia naturalium ss. In the works from the s, Bacon distinguishes the real universal from the mental universal.
Hence, the universal as the ultimate basis of predication is not the species as mental intention. Universals in the primary sense as the basis of scientific objectivity are extra-mental.
Bacon's presentation of this issue is complex. Certainly, he is not a complete Platonist in regard to universals.
To the objection that since form is individuated through its matter and whatever exists in things must exist in matter as individuated, but the universal is not such a thing, he replies that a universal is either in the mind or in things; if it is not in the former, it has to be in the latter. Hence, one cannot split apart the common matter from the particular matter or the common form from the particular form of a particular individual. In one question, Bacon rejects the view that universals are constituted only by the mind.
This sounds Platonic, but in fact for Bacon there are no Platonic universals in a separate world; rather, real universals do exist, but they are found only in and with individual things. There is a mutual interpenetration of common form and matter and proper form and matter such that there is just one individual, and so the common nature is realized in this or that individual. Bacon's answer to the possibility of a universal being present in a singular is stated as follows:.
Only three kinds of being are imaginable: either [being] in and of itself, [being] in the mind, or [being] in things, but a universal is not something that has being in and of itself and stands on its own, because then it would be a Platonic idea; neither [does it have being] in the mind, as we have seen… Again, a universal is a common nature in which particulars agree; but Socrates and Plato and [others] of this sort cannot agree in a common nature which is in them unless the nature [be] in some way duplicated in them, because a universal is nothing other than a common nature extended into particulars and existing in them as duplicated, in which all things truly exist.
And thus, without them [the particulars] there can be no universals…. For Bacon, there are two kinds of particular, the determinate here and now particular and the indeterminate particular. Bacon treats the problem of individuation both in the early Parisian lectures and the later Communia naturalium. This has given rise to the issue of Bacon's realism or his proto-nominalism. It is addressed in the next section. Here, I will briefly review his account of individuation in the Parisian lectures.
Some hold that accidents are the cause of individuation. The examples are taken from Boethius and from Al-Ghazali. Bacon raises objections and states that matter and form constitute the thing and are the causes of individuation. For Bacon, an individual is both a substance and an individual. As a substance, accident could not be the cause of individuation. First, from the formal cause, accident could be the cause of individuation, but from the efficient cause the principles of substance matter and form are the efficient causes of the one substance.
He devotes much space to whether matter alone or form alone or both are causes of individuation. He outlines the reasons why matter alone can be taken as the cause of individuation. He holds that matter is a cause of individuation and that form is a co-cause of individuation. The latter, however, is not the principal cause; it is an instrumental or formal cause. In the light of the foregoing, a key issue arises in his early works: even if Bacon disclaims being a Platonist with regard to universals, he is clearly a strong external realist.
This realism is continued in the Communia naturalium [OHI, 2—4] but with certain important qualifications. This polemical account of the discussion of Aristotle in the s is understood by Bacon as an aid for the study of theology. And now, it is clear that for Bacon, in the intention and execution of nature, the individual has definite ontological priority over genera and species.
His account becomes an attack on contemporary positions influenced by Albertus Magnus that would subordinate the individual to the universal. Species and genera are there for the sake of the production of the individual. He states, "In no other field are the authorities in such disagreement. Bacon finds a correct answer in the Metaphysics of Avicenna:. There are two kinds of nature, universal and particular, Avicenna teaches in the sixth book of [his] Metaphysics.
This universal nature is the corporeal nature that is designated in the second genus, which is [that of] body, and this nature excludes all incompatible things which are abhorrent to the whole universe, such as a vacuum. We see then that Bacon understands universal nature as supervening on a world of distinct individual natures such that corporeal action is contiguous and that a vacuum is excluded.
The "particular nature" is the directing power of the species with its individuals, and is divisible into the directive power of the species and of the individual. The example he gives is from embryology: there is the directing power of the species intending the production of the human in general; it intends the production of the individual accidentally.
And there is the directing power of the individual, which aims at the determinate individual human as such and mankind in general. He then states the ontological priority of the individual over universals as follows:. But if we would speak about the universal nature that is the directing power of the universe, [we should say that] it intends and brings about an individual first and principally , about which there is mention in the Book of the Six Principles.
Nature operates in a hidden manner in things: once a determinate man is generated, man as such is generated. And the cause of this is that one individual excels all universals in the world, for a universal is nothing but the agreement of many individuals. He distinguishes the absolute nature of an individual as something absolute, that is, "that which constitutes it and enters its essence.
One can notice that Bacon is now writing as a person with a theological interest: "And because all the things which I am treating are for the sake of theology, it is clear through theological reasons that a universal is not [favorably] compared to singulars. This account has given rise to opposing interpretations. Theodore Crowley saw in these passages the beginnings of late medieval nominalism that would find its expression in William of Ockham. Maloney challenged this reading and argued that the later Roger Bacon, like the earlier Bacon, was not a nominalist but a moderate realist.
Perhaps we should hold that there are elements of proto-nominalism in this account in the Communia naturalium. In his important essay on individuation in the fourteenth century, Jorge J. Gracia argues for seeing this text and others as the beginning of the strict tradition of late medieval nominalism. Bacon understands the soul to be a spiritual substance in union with the Body. At this early stage, he does not hold the Avicennian notion of a separate agent intellect.
In union with the body, the soul has two intellects, potential and agent. The former is directly connected with the sensitive powers and the object of this intellect is the singular material thing. The agent intellect is directed upward and knows spiritual beings in its own essence. For Bacon, there is a kind of confused innate knowledge in the soul. This is not a Platonic idea. It is more like a disposition that inclines the soul towards knowledge of the truth.
Still, it is in some sense an innate knowledge of the first principles of knowledge. The agent intellect illuminates the images and frees them from specific material conditions. The universals are then impressed on the potential intellect. In his second set of Questiones on Aristotle, Bacon identifies the potential intellect with the intellective soul, and it is now both a spiritual substance and a form of the body. As a spiritual substance, it has confused innate knowledge of spiritual substances.
As united with the body, it has become an empty slate open to knowledge. It is helped towards new knowledge by means of impressed intelligible species given by the agent intellect, and this enables the potential intellect to proceed to new knowledge.
In his Communia naturalium , Bacon explains that he wrote his account of sensation, the sensitive soul, and perception in the Perspectiva as a criticism of the common teaching of the Aristotelian teachers in the schools. Further, he comes to the conclusion in the Opus maius that the greater philosophers in the Greek, Islamic, and Christian traditions maintained that the Agent Intellect is God, the source and agent of illumination.
He now makes this position his own, and attacks those teachers who hold that the agent and the potential intellects are parts of the soul. Bacon's short treatise on the soul in CN is titled Distinctio tertia de anima. It provides an interesting window on contemporary debates c. It belongs with Aquinas's masterful polemic, De unitate intellectus contra averroistas , Siger of Brabant on Aristotle's De anima , and Richard Rufus's treatise Contra averroistas Hackett, b in the debates on Averroism. The first chapter reviews the common teaching since Having noted that before , all philosophers and theologians held that the vegetative and sensitive souls came to be by way of natural generation and that the intellectual soul came from the outside, Bacon says, "And still to this day c.
He argues that those opposed to this position rely on the Pseudo-Augustine, De spiritu et anima , and on the De ecclesiasticis dogmatibus by Gennadius. Those who follow these sources, he states, hold that "the vegetative and sensitive souls are co-created with the intellectual soul…" He describes this as a kind of 'folk-psychology'. For Bacon and "all philosophers," embryology shows that the embryo is nourished and grows prior to the infusion of the intellectual soul. Bacon states the problem as follows:. But if the vegetative and sensitive souls were co-created with the intellective soul, as many moderns teach publicly, then, they would not precede the intellective soul in being.
And so these people are forced to claim that one needs a double vegetative and sensitive soul, one that is produced from the potency of matter through the power of nature; the other is created with the intellective soul…But no authorities hold this position, and experts in philosophy, therefore, dismiss it as nonsense. In the second chapter, Bacon attacks some of the leading philosophers at Paris: "But the leaders of the common philosophers at Paris fall into other deadly errors, which the theologians contradict" [OHI, IV], For about ten years, the leader of the philosophers, "an erroneous and famous man," held that "prior to the existence of the rational soul, one must presuppose a specific substantial difference educed from the potency of matter which places man in the species of animal, such that the intellective soul does not do so…This is contrary to the philosophy of Aristotle and to all authors" [OHI, IV], — A study of the Questiones on De anima indicates the earlier Parisian tradition out of which Bacon is working Bernardini, In the third chapter, Bacon makes explicit the object of his polemic.
Bacon states: "We are concerned with this second proposition on the unity and plurality of the intellective soul. Therefore, they [the Latin Averroists] argue that the intellective soul anima intellectiva is one in number among all human beings. Therefore, they cover their error when they are compelled [to respond] stating that 'through philosophy it is not possible to hold anything else, nor is it possible to have any other position through reason alone, but only through faith alone '" [OHI, IV], — It is also closely related to the celebrated doctrine of double truth imputed to the Latin Averroists by their Franciscan opponents.
Bacon's arguments, like those of Aquinas, deal specifically with philosophical reasons for the mistaken positions of the Averroists. The first two arguments are moral arguments: if there were one identical intellect in all humans, the same person would be both virtuous and vicious. The denial that 'this individual human thinks' is contrary to both philosophy and faith. This is contrary to the Nicomachean Ethics and would lead to a destruction of moral philosophy. The remaining arguments hold that the doctrine destroys "the laws of nature," that is, of natural philosophy and psychology.
First, he presents Aristotle's arguments against the transmigration of souls. Second, he argues that this intellect would be infinitized and in power equal to God. Third, he addresses the important issue of the connection between diverse imaginations and the intellective soul. This could lead to the same person being learned and ignorant at the same time in respect of the same things.
Again, injury to the sensory organs can lead to a person becoming insane. If the sensory organs work, the existence of diverse imaginations will not differentiate the intellect in different persons. Fourth, there will be no unified object of knowledge. Bacon distinguishes between the single object of the intellect and the " intelligible species " by means of which we know that object:. For when it will be argued that the species will be multiplied in diverse persons, I concede that the diverse representations of the same thing can be present to diverse persons because the thing itself produces its species according to every diameter, as was proved in De multiplicatione specierum.
And so, just as in the diverse parts of the air the species of the same thing are diverse, and come to the eyes of different perceivers, so it is the case with the intellects of different persons. Thus, he makes a basic distinction between the thing which is the object of knowledge and the representations intelligible species by which one knows them.
Fifth, Bacon holds that the Averroists leave no room for new knowledge. Sixth, against the Averroist position that all logicians and grammarians must have the one same knowledge, Bacon holds that one must distinguish between the cognitive habit by which the soul knows anything knowable and the object of knowledge in the sense of "the object of knowledge," which is a unity. And so in a real sense, there is distinct and different knowledge in different human beings. Chapters four to seven on the parts of the soul place Bacon in the context of the Franciscan and Dominican arguments on the parts of the soul.
These chapters show that Bacon was very active in the early debates at Paris in which the unity of substantial form in Aquinas was strongly criticized by the Franciscan School. Bacon is so critical of Aquinas's position that he deems it heretical. He defends the notion of plurality of forms while strongly arguing for the essential substantial unity of the human being. Bacon also uses his remarks to let the reader know that his study of Perspectiva was undertaken to criticize the common teaching on natural philosophy including psychology and medicine at the University of Paris.
This short treatise has the advantage of contextualizing Bacon's works in the s in terms of the debates on Latin Averroism. It would appear that Bacon, like Bonaventure and Pecham, was an explicit opponent of the young teachers of the Arts at Paris, especially Siger of Brabant. That Pecham and Bacon shared a common philosophical position has recently been disputed Hackett, forthcoming. And it would appear that Bacon's treatises such as the Perspectiva were written with this context in mind. Since, as we have noted above, Bacon provided a philosophical critique of the issues concerning Latin Averroism already as a teacher at Paris in the s, we should see his intervention in the debates of —72 as the criticism of an emeritus Professor of Philosophy, now engaged with the theological arguments of the schools at Paris.
At the beginning of the Opus maius and related works, Bacon offers a structural critique of scholastic practice in the universities. He favors both language study and science over the "Sentence-Method" as a way of interpreting the texts of Scripture. And he advocates training in mathematics and the sciences as requirements for students in theology. Second, Bacon's later works on language and science are written in the specific historical and political context of the Mongol invasion of Europe, the sack of Baghdad in by the Mongols, and the geo-political situation of a Europe hemmed in by both the Mongols and Islam.
The wider historical context for Bacon's concerns has recently been outlined by Amanda Power Power, The general context is theological and Franciscan: the arts and sciences leading to human well being in this world and the next. It is also clear that Bacon is constructing a "new model" for medieval philosophy, one in which Aristotelian concerns are taken up and transcended in a Neo-Platonism adapted to moral philosophy and Christian theology. Metaphysics is taken up and completed in Moral Philosophy.
The latter becomes the end of linguistic and scientific study. Logic is reduced to mathematics, and the applications of mathematics become central to an understanding of the sciences Perler, The applications of mathematics can in turn be used in religion and theology. Therefore, in his later works, especially in the Perspectiva and Scientia experimentalis , Bacon will define experientia-experimentum in a distinctly new manner, one that takes up and also goes beyond the use of this term in Aristotle and in Bacon's own Questiones from the s.
Peter King has recently claimed that Ockham was the first to create this new definition of experientia-experimentum He is correct that this definition is found in Ockham, but not in claiming that this concept began with Ockham. The concept is formulated in the scientific works of Roger Bacon and is found in a number of Franciscan writers including John Pecham well before the age of Ockham Hackett, Part one examines "the causes of error" in education and is critical of some theological limits on science.
These causes are: belief in unworthy authority; long custom; uncritical popular opinion; concealment of academic ignorance in a display of rhetorical wisdom. Part two contains the pre-Cartesian view of truth and wisdom as a result of a universal revelation to the Hebrews that was transmitted through the Greeks, Romans, and Islam to medieval Christianity.
This view would be influential in Philosophy up to the age of Francis Bacon and Descartes. Roger Bacon links it to a doctrine of illumination taken from Augustine, Avicenna, and the commentary on the Pseudo-Ptolemy: Centiloquium.
He contrasts the tradition of the great philosophers such as Plato and Aristotle with the mythical traditions from ancient times. Part three deals with language study, grammar, semantics, and semiotics, and contains Bacon's general theory of signs. The discovery by the late Jan Pinborg and his colleagues of De Signis , a missing section of part three, led to intense study of Bacon's semiotics and the philosophy of language in his later works.
Bacon's proposals are radical. Bacon's concerns with language in his later works transgress the disciplinary boundaries of the medieval university. First, he demands that the universities study the Wisdom languages, i. Bacon takes Latin as a model for a natural language, the "mother language" of the West. For Bacon, this language is dependent on Greek and Hebrew.
He distinguishes the "vulgar language" or "language of the laity" from the "language of learning" of the clergy. For him, vulgar language cannot be used in learning; it does not have an adequate technical vocabulary. Bacon's relative originality consists in the fact that he brings together the semantic and semiotic concerns of both Arts and Theology or, as one might say, Aristotle and Augustine. From these concerns, he develops his own novel theory of the sign.
Indeed, Bacon uses the words signification and its cognates in a manner quite different from the traditional position. The commonly used medieval definition of a sign was substitutional or representational: "A sign is that which shows itself to the senses and presents something else to the intellect. The expressions in language stand for the thoughts of the speaker and represent them to the hearer. In De signis , Bacon provides the following definition: "For the sign is that which, offered to the senses or to the intellect , represents itself to that intellect, since not every sign is offered to the senses as the common definition of sign supposes.
However, on the testimony of Aristotle, another kind is offered only to the intellect. Some interpreters claim that Bacon's definition of sign is close to that of to that of Augustine in De doctrina Christiana : "For a sign is something that apart from the impression it gives to the senses, also causes something else from itself to be present to the mind. One can see that Bacon in a manner uncommon for his times relates Augustine's definition of sign to the inferential notion of sign in the works of Aristotle.
And so one can also see how Bacon, influenced by Kilwardby and Fischacre, unites the different concerns of the philosopher and the theologian. Bacon continues and states: "The sign is in the predicament of relation. The theologians were aware of a twofold relation: that of sign to thing signified and sign to the perceiver of the sign. For the majority of theologians, the first relation is an essential and permanent relation; the latter is accidental and non-permanent. Bacon reverses this. He remarks,.
The sign is in the predicament of relation and is spoken of essentially in reference to the one for whom it signifies. For it posits that thing in act when the sign itself is in act and in potency when the sign itself is in potency.
But unless some were able to conceive by means of this sign, it would be void and vain. Indeed, it would not be a sign, but would have remained a sign only according to the substance of a sign. But it would not be a definition of the sign, just as the substance of the father remains when the son is dead, but the relation of paternity is lost.
And so it is not sufficient that a sign have reference to what it signifies accusative in order to be a sign; it is also required that it have an interpreter dative for whom it signifies. In medieval theology, the thing signified accusative has priority, and was true even if there were no interpreters. The notion of this two-way relation is found in Bonaventure, Rufus, and Fishacre among others, and the thing signified holds ontological priority over the relationship of sign to perceiver.
The forthcoming edition of Fishacre on signs will enable scholars to gain a better view of the issues at stake in this debate. For Bacon, the communicative relation to a hearer is basic, and the relation to the thing signified is important but secondary in the whole context of communication. The common theological teaching held that the relation of sign to thing signified is primary and fundamental.
Once a name has been instituted, it does not change. Against Rufus and Bonaventure, Bacon held that this introduced ambiguity into language. Even in the case of ordinary signs such as that of a tavern, they remain a sign only potentially if there are no customers or staff. Bacon's own classification of signs introduces distinctions that reflect an integration of Augustine and Aristotle:.
The distinction between 1 and 2 is taken from Augustine's De doctrina Christiana. Bacon himself claims that he worked out the typology himself prior to finding it in Augustine's great work on interpretation. Modern scholars, however, believe that he must in some way have borrowed it from Augustine. Type 1 signs occur naturally as part of the agency of nature. Type 2 are signs only because they have been willfully created as such by deliberation; included here are linguistic and non-linguistic signs.
However, Type 2. These sounds and groans are products of nature and happen instinctively but in an "animate" action. Interjections are a problem. They are parts of language, conventional signs, and so conceptual, yet they are emitted suddenly and often due to pain. They are similar in a way to the groans of animals Type 2. This discussion is common to writers on grammar and logic from the s, especially in the works of Richard Kilwardby and similar authors.
The signs in 1. Maloney has argued that Aristotle's De anima plays an important role in Bacon's distinction between signs by nature and signs by intention. And so the relation of sign to thing is indirect. In this way, Bacon substitutes an extensional relation for an intensional relation. Words can directly refer to individual things, be they single objects in the world, mental objects, or philosophical concepts. Primarily, then, words refer strictly to the present object. Reference to past or future objects will require the extension of univocal terms by means of analogy or metaphor.
Simply because a sign exists, it will not follow from that alone that the object of the sign exists. As we saw above, without the interpreter of the sign, a sign is a sign in name only or potentially. As Umberto Eco puts it, "Bacon definitely destroys the semiotic triangle that was formulated since Plato, by which the relationship between words and referents is mediated by the idea, or by the concept, or by the definition.
Here one can see the preparation of the ground for the semiotics of William of Ockham and late medieval nominalism.
Parts four, five, and six of the Opus maius present the main themes of Bacon's contribution to scientific education. It is important to see his main contribution to science as one who advocated "scientific education" in an Arts Faculty that was predominantly dedicated to linguistic arts.
Bacon had a very wide reading knowledge of most of the newly translated work from Greek, Jewish, and Islamic Philosophy and Science. His major claim to fame in science is that he is the first Latin Western thinker to comprehend and write on most of the ancient sources of optics. This tradition would be formulated as teaching text by his contemporaries Pecham and Witelo, and then taken up by the tradition leading to Kepler and Descartes.
In his Perspectiva and De scientia experimentali , Bacon outlines a sketch for a scientific method, one that takes optics as the model for an experimental science. In fact, he succeeded in his endeavor in that Perspectiva was added to the four traditional university subjects of the quadrivium : arithmetic, geometry, astronomy, music. Opus maius , Part four, deals with mathematics and the applications of mathematics.
Bacon presents reasons for a reduction of logic to mathematics a kind of reversal of modern logicism and sees mathematics as the key to an understanding of nature Perler, Clearly, he is proclaiming the "usefulness" of mathematics for knowledge; he is not doing mathematical theory. It used to be thought that Bacon was a Platonist in his view of the absolute priority of mathematics. More recently, that view has been seriously qualified. He does not reduce physics to mathematics. Indeed, his explicit work on mathematics, the Communia mathematica , is not an exercise in mathematics, but a presentation of the "common notions" that are important for a variety of mathematical practices.
Bacon himself acknowledges those who were better mathematicians, namely, John of London, Pierre de Maricourt, and Campanus of Novara Molland in Hackett, a. In general, Bacon is more interested in how mathematics can contribute to knowledge of the world as an aid to missionary activity. He sent a map of the world to the Pope. Federici Vescovini has now provided the essential context and linkage between medieval magic and philosophy, enabling scholars to grasp the dimensions of fate and freedom as understood by medieval philosophers and theologians.
And since he held to a doctrine of universal radiation in nature, he had to account for the influence of the heavens on the human body and hence indirectly on the human mind. Much of the polemic in his later works consists of a justification of this interest in an astrologically necessitated universe in the face of traditional theological objections. These works play a big role as background for his natural philosophy in De multiplicatione specierum. He was also interested in alchemy. It was his determined interest in some of these areas of study that led to disagreement with his superiors in the Franciscan Order, specifically, Bonaventure.
Bacon's treatise De multiplicatione specierum , his major later work on physics, written before , is closely related to the study of light, vision, and perception in the Perspectiva. David C. Lindberg DMP, Introduction has noted that Bacon takes Grosseteste's physics of light, a development of Al-Kindi's universal radiation of force, out of its metaphysical background and develops a universal doctrine of physical causation.
Lindberg had already traced the history of the emanation theory of light from Plotinus to Bacon. What Bacon achieves is a comprehensive theory of physical force divorced from psychological, moral, and religious interpretation. As Lindberg puts it DMP, Introduction Bacon does not deal in this work with the divine illumination of the intellect, universal hylomorphism, the plurality of forms properly qualified , and the separability of soul. He presents a full theory of the physics of light.
Species is the first effect of any natural agent. As Lindberg puts it DMP, Introduction , "This is a complete physical and mathematical analysis of the radiation of force--and, thus, of natural causation. The use of 'species' in this account is not that of Porphyry's logic or the perceptual notion of likeness. It is "the force or power by which any object acts on its surroundings. This is a universal theory of natural causation as the background for his philosophy of vision and perception.
Most importantly, species is a univocal product of the agent. The first immediate effect of any natural action is definite, specific, and uniform. This production is not the imparting or imposition of an external form. The effect of the species is to bring forth the form out of the active potency of the recipient matter.
DMS, 6—7. This is also the first attempt in the Latin world to provide separate domains for material and spiritual being. Bacon is adamant on this point: spiritual and material being are entirely separate. Natural causation occurs "naturally," according to regular processes or laws of nature. There is no "spiritual being" in the material medium as was commonly taught by other scholastic philosophers. That is, Bacon objected to the use of the term 'spiritual being in the medium'.
No, for Bacon, universal causation is corporeal and material, and matter itself is not just pure potentiality but is rather something positive in itself. Hence, the general philosophy of nature prepares the theoretical ground for the specific application of mathematics to matters of vision and perception. It also allows for and requires a metaphorical extension of these terms to moral and religious domains. Recent scholarship on Bacon's philosophy of nature, especially that of Yael Raizman-Kedar Raizman-Kedar, ; Raizman-Kedar, dissertation, University of Haifa, places great emphasis on the importance of the concept of species for Bacon's account of perception and mind.
She is correct to note that Bacon places a kind of natural activity in the mind via species. This leads in her view to natural species having a direct role in intellectual activity as such. One could speak of the direct presence of material, corporeal species in the intellect itself see section 5. Here, and also in the Perspectiva , we can see the importance of the cogitative sense, as it takes on an administrative role in animals analogous to reason in human beings. But in this life, for Bacon, human beings cannot know things in the world without the presence of species in the mind. Species as the expression of universal agency act naturally in nature and in the mind in a certain limited sense.
Yet, Raizman-Kedar claims, "the very same species issued by physical objects operate qua material species within the intellect as well. In this way, Bacon sets the intellect as separate from the natural world not in an essential way, but rather in degree my italics , thus supplying a theoretical justification for the ability to access and know nature. Raizman-Kedar, , Further, she carefully distinguishes between the role of hearing and sight in the knowledge process.
A forthcoming paper by Jeremiah Hackett raises questions about this conclusion. He points to a significant problem with the translation of a central passage in Perspectiva in support of this position. Yes, the material species are a necessary but not a sufficient element in the acquisition of pure intellectual knowledge. Without the illuminative process within from above, pure intellectual vision is blocked.
It is not at all clear that one can claim that Bacon is a material monist. Bacon's separation of the account of physical species in the DMP could lead one to think he has to be a material monist, even with regard to species in the medium, sense, and reason. And there is one sense in which this is true. Hence, at a deep level, Bacon is a substance dualist medieval version. In his Perspectiva and related works, Bacon presents his model for a careful and detailed application of mathematics to the study of nature and mind.
In imitation of the De aspectibus of Alhacen Ibn al-Haytham , he provided an application of geometry to vision that within the terms of reference of his times was successful. But he is critical of both Alhacen and Ptolemy. He sees himself as answering some of the optical problems not solved by either author. Bacon's approach to vision and perception, however, is not an exercise in modern mathematical optics. It should be seen as the sketch of a physics of light as the basis for a philosophy of perception and mind.
The account of visual perception in terms of natural philosophy, medicine, and philosophy of mind is found in Part one and a section of Part two. The account of Perspectiva sets out a consideration of direct, reflected, and refracted rays, and ends with the application of geometrical models for moral and religious considerations. Part one and also distinctiones one and two of Part two deal with the structure of the eye, problems of vision, and visual errors.
The theory of the eye is taken from the Galenic tradition handed down in Constantine the African's translation of Hunyan Ibn Isaq and from Avicenna and Alhacen. For this tradition, vision occurs when the crystalline humor is altered by the intromission of visual species from the object. Vision is completed when the species proceeds through the vitreous humor to the optic nerve and through this to the common nerve. It is here that a common visual judgment is made. Throughout the text, Bacon makes reference to the kind of visual knowledge possessed by animals, especially in the context of a discussion of the cogitative sense Hackett, a.
Bacon follows Ibn al-Haytham and imposes a geometrical model on the eye, enabling him to give a geometrical account of radiation through the eye. How then does one avoid confusion in vision and gain verifiable clarity? For Bacon, the perpendicular ray is primary; the other rays are treated as cases of indirect vision, refracted in the rear surface of the crystalline humor.
Bacon is next concerned with optical illusions, inverted images, magnification, vision of distant objects, the moon illusion, and such matters. He seeks in a rational and experimental manner to solve the puzzles found in Ptolemy, Alhacen, and others. Still, he is a child of his sources, which do not provide him with the more advanced data and mathematical method that arose only later, in the seventeenth century.
But they do provide him with a functional qualitative geometry of the eye and vision based on the best Greek and Islamic science. Bacon is committed to an intromission theory of vision, though he combines it with an extramissionist theory that avoids the anthropomorphisms of earlier extramissionist theories. He uses the latter theory mainly to emphasize the active role of the eye in vision. In Parts two and three, he is to some extent successful in applying geometry to problems of direct, reflected, and refracted vision.
He moved the study of these matters to a new level. The geometrical arguments are worked out with careful diagrams and various appeals are made to "experimental" conditions. What are these conditions? Some of them are simple thought-experiments or even reports of actual experiments from earlier writers. It seems clear, however, that Bacon himself did experimental work with pinhole images, lenses, and discrete observations.
This does not lead to a pure geometrization of nature, however, and he inevitably falls back on physical, perceptual, and metaphysical arguments. One might argue that he lacks the notion of infinity that is present in modern geometry. Bacon introduces another important item for science.
He refers to the "laws of reflection and refraction" as leges communes nature. In his account of nature in Communia naturalium and the later works in general, Bacon's view is that a general law of nature governs universal force. This universal law of nature is imposed on a world of Aristotelian natures. This notion would have a significant future in experimental science. Bacon ends Part three with an account of how a better understanding of natural phenomena could lead to a more accurate knowledge of the natural phenomena mentioned in Scripture.
He finds in visual phenomena significant metaphors and analogies for use in moral and religious teaching. A solution to David C. Lindberg's queries about Bacon's attempt to combine elements of the intromissionist and extramissionist theories of vision is addressed here. At one level, it seems to be an akward combination of two conflicting theories of vision.
This combination can be understood when one notes that Bacon is making use of the important issue of grace and free will issue as the moral-religious background for his discussion of vision see Hackett, In other words, genuine theological concerns influence the manner in which Bacon constructs his analysis of vision in the Perspectiva. Thus, the analyses of Ptolemy and Alhacen had to be synthesized within a definite theological framework.
Direct evidence of Bacon's influence here in making science available for an educated public is seen in the use of his work by Pierre de Limoges in his influential text, De oculo morali On the Moral Eye , written at Paris between and All of this suggests Pierre de Limoges, magnus theologus et astronomus as a very early reader of Bacon's works Newhauser, Both are genuinely committed to the improvement of the task of the preacher.
Here, we see the priority for Bacon of preaching over theology, or rather, the latter is in service to the former Johnson, Presupposing the Perspectiva , in De scientia experimentali and in related works on the halo and on burning mirrors Bacon situates this new scientific practice as a desired area of study in the medieval university. It is consequent on the study of Perspectiva. Starting from Aristotle's account of empeiria experience , Bacon argues that logical argument alone, even when it originates from experience, is not sufficient for the "verification of things".
Even arguments that have their origins in experience will need to be verified by means of an intuition of the things in the world. He distinguishes scientific argument from moral and religious mystical intuition, although he does allow for the notion of a revealed intuition in science. It is this element that clearly separates Bacon's practice from that of modern science. Just as in his concern with the certification of language to gain individual reference, so too in science, Bacon clearly wishes to have a way of certification for knowledge of the individual.
His aim is to provide a method for science , one that is analogous to the use of logic to test validity in arguments. This new practical method consists of a combination of mathematics and detailed experiential descriptions of discrete phenomena in nature. It would be distinguished from the conjurations of magic and from moral and religious belief.
It would also be different from philosophy of nature and from broad optical knowledge. These two areas are important for experimental science, but they constitute general principles, so that in themselves and without experiment, they do not provide access to minute, detailed experiments. Nevertheless, for his description of the first example of an experimental science, the study of the rainbow, Bacon depends on the accounts handed on by Aristotle, Seneca, and Avicenna. He is not uncritical of these accounts. The context for Bacon's writing on topics from the Meteorology of Aristotle came from the presence in Paris of the new translation of this work from Greek into Latin.
With the recent critical edition of the Aristoteles Latinus version of the Meteorology , it is clear that Bacon is deliberately offering a criticism of William of Moerbeke's translation Hackett, Bacon contends that the translations are not adequate and that the translator did not know the required sciences, especially Perspectiva , proposing instead a more accurate mathematical analysis of the phenomenon of the rainbow. Bacon's own important contribution is to be found in his calculation of the measured value of 42 degrees for the maximum elevation of the rainbow.
This was probably done with an astrolabe, and in this, Bacon advocates the skillful mathematical use of instruments for an experimental science. That Bacon had mathematical competence in this field can be seen in his account of the halo in the Opus tertiium OQHI and in his complex arguments in De speculis comburentibus. Bacon takes up Grosseteste's theory of refraction and tries to work out the difficulties in the latter. It would appear at first glance that Bacon is rejecting the notion of refraction out of hand Lindberg , but in fact he is only demonstrating that refraction as formulated by Grosseteste did not make experimental or rational sense.
Bacon knew the rules governing the geometry of refraction. Important here is his emphasis on the role of individual drops of water for the process of reflection and refraction. A correct account of the rainbow would appear some forty years after Bacon in the De iride of Theodoric of Freiberg d. An important item here is the discovery of magnetism. It would seem that Bacon is reporting on the actual experimental work of Magister Petrus Peregrinus fl.
Bacon has been lauded down the centuries for his medical learning, but recent scholarship has limited the number of works attributed to Bacon. Still, it is important to note that he did draw on medical practice to set out rules and procedures. The very concept of the 'prolongation of life' so forcefully proposed by Bacon in his later works found very receptive readers at the Papal Curia in Viterbo. The Papal Curia had by become a center for medical and scientific study.
The conclusion to the De scientia experimentali is important. Bacon presents the ideal of the "philosophical chancellor" who will organize science and its technological products for the benefit of Res publica Christiana. Stewart C. Easton proposed that this work was the guiding vision for Bacon's reform of science. Williams has argued that Bacon completed the edition of this work after his return to Oxford ca.
Still, there is much cross reference between this work and Bacon's writings in Paris ca. Lindberg in Hackett, a has given a succinct summary of Bacon's model for an experimental science [RBS]. He sees four main aspects. First, Bacon's perspectival theories were not his own creation. He took the best available materials from Greek and Islamic scholars and produced his own synthesis. Second, there is much evidence that Bacon himself did mathematical work and experiments with visual phenomena such as pinhole images and measurement of the visual field.
Third, as seen above, Bacon correctly calculated the maximum degree of elevation for the rainbow. Fourth, the experiments in Bacon, especially in the Perspectiva served "theoretically significant functions" by supplying observational data that required explanation in terms of a given optical theory. The usual role of experiment in Bacon is to "confirm, refute, or challenge theoretical claims. One might have expected Bacon to have given equal treatment to astronomy, but in this field he was a child of his time. He discusses the pros and cons in scholastic, but does not advance the field as he did for Perspectiva.
Bacon describes the object of moral inquiry as follows: "This science is preeminently active, that is, operative, and deals with our actions in this life and the other life" [RBMP], 3. It is focused on human action. Of course, many human actions deal with issues that are the concern of the natural and linguistic sciences. Bacon notes that these sciences are active and operative but concerned "…with artificial and natural works which refer to the speculative intellect, and they are not concerned with those things which refer to the practical intellect, which is called practical because it exercises operations of good and evil " [RBMP], 3.
These works of the human being operabilia are "…more difficult to know than the objects of speculative knowledge. For Bacon, the human ability to deal with these topics is affected by a certain corruption of the human will. Moral science has two parts. The first is speculative, dealing with ultimate moral truths. The second deals with the process of moral persuasion: "The practical part is related to the first part as the curing of the sick and the conserving of health, which are treated in practical medicine, are related to that part of medicine which teaches what health is…" [RBMP], Part one deals with the object and method of morals science and with an outline of a philosophical anthropology based on Platonic, Aristotelian, and Stoic texts in which Bacon argues for an Augustinian view of the place of human beings in the world.
This includes a section on metaphysical proof for God's existence. And the ancient source texts are treated as testifying to the universal religion of Christianity. Part two is a very brief outline of the structure of social life, taken from Avicenna. Part three, the most substantial in the book, is concerned with virtue and vice. Bacon's own text for this part of the Opus maius still exists and one can see his personal editorial remarks in the margins. He did not have time to write a formal treatise, and so he presents an anthology of texts from Seneca and excerpts from Cicero with comment.