Adelard s Questions and Ockham s Razor: Connections between Medieval Philosophy and Modern Science By Carolyn Scearce

Transcription

1 Discovery Guides Adelard s Questions and Ockham s Razor: Connections between Medieval Philosophy and Modern Science By Carolyn Scearce Introduction Science, as a word in the medieval vocabulary, seems alien as read from a strictly modern context. For the Medieval mind, science served as any body of knowledge that could be systematized. Subjects we would not consider science today fell under its auspices, including, most notably, theology. Theology interwove itself through medieval culture and learning, and was not perceived as a truly separate discipline from philosophy or the study of natural phenomena. The field of learning that most nearly resembled modern science was natural philosophy. Natural philosophers sought explanations and causation for substances and actions occurring in the natural world. However, it would be wrong to look for direct synonymy between medieval natural philosophy and modern science. Hienrich Khunrath, Amphitheater of Eternal Wisdom, depiction of a medieval alchemist s lab Medieval natural philosophers did not engage in the sort of systematic programs of research in which modern scientists participate. They addressed whatever large ranging philosophical questions or trivial pursuits happened to engage their individual attentions. They focused their attention on a range of subjects that do not always directly correspond to modern scientific disciplines. Their interests in astronomy, physics, botany, agriculture, medicine, and mathematics may be roughly comparable to modern subjects, but subjects such as astrology and alchemy evoke a greater sense of dissidence. Astrology is a subject now entirely outside of the realm of accepted modern science. After the middle ages, alchemy engendered and was eventually replaced by chemistry as a scientific discipline. The seemingly haphazard approach, the apparently eccentric interests of the Middle Ages, can conceal the avaricious intellectual curiosity and keen analytical approach exhibited by medieval scholarship, particularly in the high Middle Ages. Though the age started in the decline of an empire, and ended in the wake of a devastating plague, the Middle Ages was no fallow time in the development of human thought ProQuest Released November

2 The natural philosophy, theology, and culture of the middle ages contributed to the formation of the modern sciences. However, it is not always a direct contribution. Throughout the passage of history, ideas may experience radical transformations. This does not negate their place in the history of knowledge. Few intellectual revolutions are so radical that they truly deconstruct all the pieces of the material on which the preceding paradigms were formed. Other ideas wane in one generation only to be reborn in an altered but still recognizable form in another generation. The most substantial contribution that medieval philosophy made to modern science is not the legacy of individual ideas, or even the introduction of new disciplines. Instead, medieval philosophers laid down much of the intellectual foundation, and articulated important assumptions on which the edifice of modern science is built. Arab astronomers at work, as depicted in a medieval manuscript. 0today/CHAISSON/AT302/HTML/AT30201.HTM Before approaching the intellectual contribution of the Middle Ages, it is necessary to provide some overview of the historical context in which these ideas were formed. For this reason, the essay that follows will briefly outline the history of the Middle Ages and highlight a few important historical figures; it will look at some intellectual trends and conclude by examining some of the connections that exist between medieval philosophy and modern science. The Early Middle Ages During the transition between Late Antiquity and the Middle Ages a number of pivotal events and people exerted a long lasting influence that helped to shape the intellectual character of the medieval period. Constantine, a fourth century Roman emperor, reshaped both the map and the religious direction of the age to follow. Prior to Constantine s rule, Rome viewed Christianity with suspicion and distaste. During his lifetime, however, Constantine sanctioned and on his death bed converted to Christianity. By this change, Christianity went from being a persecuted sect to being allied with temporal authority. Additionally, Constantine moved the capitol of the empire to Constantinople. This move led to the division of the empire into two parts, the Greek speaking east and the Latin 2

3 speaking west. While the eastern empire survived for another thousand years, social and political instability eroded the western empire to a shadow of its former authority. Germanic Migration. The western Roman Empire is in orange, the eastern in blue. Maps.com World History Maps The intellectual heritage on which Western Culture, and consequently modern science, is founded rests not on the empire that survived, but on the empire that fell. From the fragments of this disintegrating empire, new cultures were formed. In the fifth century Vandals sacked Rome, and in the centuries that followed Rome was periodically invaded by various barbarian groups. Barbarians may have conquered Rome in a physical sense, but Rome returned the favor in a cultural and moral sense. Even in decline Roman culture still had much to offer in the form of language, literature, laws, education, the new state religion of Christianity, and material artifacts. The physical conquest of Western Europe by Rome may have come to an end around the fifth century, but its cultural influence lasts to modern times. To the varied tribes and kingdoms of the west, Latin became the second language of the literate classes. This shared language allowed the various Western European kingdoms to create a single intellectual community. The Latin west did not rebuild its civilization in isolation. The Medieval period is really a story of three faiths and the interactions of their three cultures: the Christianity of the Byzantine East and the Catholic West, the Islamic Middle East, and a scattered Jewish Vandals sacking Rome 3

4 population (Durant, 1950). Though this Discovery Guide focuses most directly on the Latin West, the importance of the interaction between Arabic and western culture cannot be overlooked in developing a coherent narrative relating the intellectual development of medieval European culture. Cultural borrowing plays an important role in the story of the intellectual development of the Middle Ages. Medieval culture borrowed from Roman culture, which had previously borrowed from Greek culture. Medieval society developed its social structure on Roman conventions, but Greek philosophy played an important role in the development of medieval philosophy. The works of Plato and his student Aristotle defined much of the philosophical debate of the Middle Ages. The two philosophers held very different views on the nature of reality. Plato privileged conceptual reality over physical reality. He doubted the ability of sensory information to provide a reliable picture of ultimate reality. Since human experience is mediated through sensory interaction, Plato did not offer much hope for humans to genuinely comprehend ultimate reality. Aristotle, on the other hand, believed that physical reality was ultimate reality. He believed the physical world was causal and intelligible. Sensory information was usually reliable, and with the aid of reason and sensory input, humans could gain a reliable understanding of the universe. The differing views of Plato and Aristotle became an important point of contention in the Middle Ages. In the early Middle Ages, however, Platonic philosophy held sway, as can be seen in the contribution of two very important intellectuals of the time, Augustine and Boethius. Saint Augustine, A.D. ns/augustine.html Augustine, the most influential theologian of the early Middle Ages, initially resisted, but was eventually converted to the Christian faith of his mother. He lived during the fifth century. Though he resided in North Africa during the sack of Rome, news of its capture troubled him and profoundly influenced his latter work; he dedicated 14 years to his response in The City of God. Augustine s intellectual leanings attracted him to Platonic philosophy. He shaped his theology around Platonic thought, taking what aspects he could readily reconcile with his faith and discarding the rest. He advocated co-opting any useful knowledge from paganism, and felt that with the use of reason, Christians could beat pagans at their own game. Augustine believed that knowledge could only be obtained through direct sensory experience. Since history and even language were not accessible to direct experience, he felt it necessary to accept authority in the process of seeking truth 4

5 (Williams, 2007). Faith and authority served as the truth seekers starting point, and then reason could be used to test faith and authority to confirm truth. Boethius, a sixth century philosopher and statesman, served as consol under Goth occupied Rome. Son of a prominent senatorial family, in his youth he received 18 years of education in Athens. Prompted by concern over the decline in Greek literacy, Boethius embarked on an ambitious translation project. He intended to translate all of Aristotle s philosophical and ethical works as well as the complete dialogues of Plato from Greek into Latin (Luscombe, 1997). Boethius succeeded in translating Aristotle s works on logic, and also contributed educational texts on mathematics and music. An accusation of treason interrupted Boethius translation efforts; he was thrown into prison where he wrote The Consolation of Philosophy. Though generally Boethius was more comfortable with Aristotle than Augustine was, in this most influential of his original works, he held a Platonic rather than Aristotelian outlook. Soon after finishing this work he was executed. Though Augustine expressed some interest in natural philosophy, he felt the highest purpose of mankind was to turn their thoughts to God. The best case he made for the study of natural philosophy was that Christians should not make themselves appear ridiculous in their description of natural phenomena by advocating views that better educated people knew to be untrue (Williams, 2007). Augustine s theology dominated Medieval thought for over half a millennia and through it a second hand Platonism. The only actual Platonic text that was passed down to the early Middle Ages was a partial rendition of the Timaeus. Boethius original and translated works served as a major part of the early medieval educational curriculum. A number of Boethius Aristotelian translations were lost, at least temporarily, before they could be transmitted to his immediate successors. Platonic philosophy is not as conducive to the study of natural philosophy as are Aristotelian views. After Boethius, early medieval thinkers had no access to Aristotle s metaphysical thought or his study of natural philosophy. Times were marked by political and civil instability, and the leisure required for intellectual pursuit was frequently lacking. Consequently, it is hardly surprising that the early Middle Ages did not contribute much to the pursuit of natural philosophy. Arabic Scholarship in the 8 th to 11 th centuries While natural philosophy languished in the Latin west, events in the Middle East lead The spread of Islam in the 7 th & 8 th centuries Source: Maps.com World History Maps 5

6 Illustration of a 13 th century Persian astrolabe olabe to a surprising resurgence of scholarship. The development of Islam among the nomadic tribes of Arabia helped to unify an otherwise divided culture. In just the matter of centuries these warring tribes recreated themselves into the most militarily and intellectually formidable culture of the central Middle Ages. From the 8 th to the 11 th century Arabic culture experienced a period of intellectual efflorescence (Durant, 1950). An important stimulus to this time of intellectual expansion was the translation of Greek and Syrian texts into Arabic. Among the translated materials were much of the extant texts on Greek medicine, natural philosophy, and mathematics (Lindberg, 1992). Works of Plato and Aristotle, then lost to the West, were contained in Arabic libraries. Islamic scholars not only translated, but wrote extensive commentaries on Greek works, made corrections, and expanded on knowledge where they were able. By the time Arabic scholarship reached its climax in the 11 th century, it had surpassed Greek learning in a number of fields and created new branches of Mathematics and Natural Philosophy. Arabic astronomers provided improved observations and invented the astrolabe. Commentators such as Avicenna and Averroes wrote extensive texts explaining the metaphysics and natural philosophy of Aristotle. Arabic alchemists preformed extensive chemical experiments in attempting to determine the nature of matter and in the process invented the method for distillation. From Greek mathematics, Arabic scholars developed Algebra, and went on to invent Trigonometry. Further improvements were added to fields such as medicine, botany, and zoology (Durant, 1950). As the century progressed, religious and political forces began to curb this period of intellectual expansion. Even in decline, Arabic libraries contained a wealth of knowledge that would contribute to a further period of intellectual outpouring. Medieval Education and the Rise of Universities Meanwhile, back in Europe, the early Middle Ages saw a decline of not only Greek literacy but Latin as well. In the face of successive barbarian invasions, the The Coronation of Charlemagne (AD 800). htm 6

7 Roman aristocracy abandoned the city for rural estates. Rome s population decreased and few schools remained open. Some learning was preserved and transmitted in private households and monasteries. Medieval education was modeled on the Roman curriculum of the trivium, consisting of grammar, rhetoric, and logic, and the quadrivium consisting of arithmetic, geometry, astronomy, and music (Durant, 1950). The reign of Charlemagne ( ) heralded a brief interlude of cultural expansion. Charlemagne himself was only marginally literate; he could read but was never able to learn to write. Still, he patronized the arts and enthusiastically embraced learning. Charlemagne exhorted every cathedral and monastery to establish schools (Luscombe, 1997). The Carolingian renaissance did not long outlast Charlemagne s life time. The establishment of monastery and cathedral schools, however, led to an increasing literacy rate even after the Carolingian dynasty went into decline. A university class, (1350s). The 12 th and 13 th centuries saw the establishment of the earliest medieval universities. Informal schools were established in various regions of Europe, when teachers began to collect students. Universities initially emerged not as physical edifices, but as associations of students who contracted lecturers to teach them. Universities were formalized when they were granted charters. The University of Bologna can trace its origins back to the late 11 th century and received its charter in the 12 th century. Other early universities established in Europe include the University of Paris in France and Oxford in England. They modeled the structure of schooling after the trade guilds. After five years of study at a university a student might obtain a bachelors degree after passing private and public examination. After three more years of additional study and further public examination, a student might obtain a masters degree. The masters degree entitled a scholar to teach anywhere in Christendom (Durant, 1950). The development of universities during the Middle Ages provided and still provides an important center for scholarship and intellectual exchange. At universities scholars from all over Europe would come together as a single student body. Aided by a common tongue, the universities help forge a single intellectual community over the face of the greater part of a continent. Since the Middle Ages, the university has become such an entrenched institution in intellectual development, it is hard to picture the face of scholarship outside of its context. The modern disciplines of the sciences are particularly deeply rooted within this academic hierarchy that was initially developed in the Middle Ages. 7

8 The Rediscovery of Aristotle Aristotle and Plato in Raphael s School of Athens. Aristotle's hand symbolizes his realistim, Plato's his mysticism view. lectures/lec03.html Arabic learning reached its climax, just as the simultaneous revival of learning in the west created a receptive audience for the fruits of Arabic scholarship. In the latter part of the 11 th century Christian scholars got the first real taste for the intellectual wealth housed in Arabic libraries as the Christian reconquest of Spain opened the doors to libraries housed in Spanish cities such as Toledo (Rubenstein, 2003). A second translation effort commenced as Arabic texts were translated into Latin. As more texts became available, scholars attempted to absorb the material into the university curriculum. It fell to the 13 th century scholars to try to assimilate the new learning. Among the texts rediscovered during the 12 th and 13 th centuries were many by Aristotle. The depth and breath of Aristotle s works left his new audience breathless. In a phrase coined by Dante in the 14 th century, Aristotle was the master of those who know. To others he was simply known as The Philosopher (Rubenstein, 2003). The study of Aristotle s logic that had remained continuous throughout the Middle Ages had to a certain extent prepared scholars for his work. The intellectual trend towards an Aristotelian reasoning could already be seen in the work of philosophers and theologians such as Peter Abelard. Working from just the logical texts, Abelard had attracted quite an enthusiastic audience to his lectures regarding the application of logic to the authoritative texts of the Christian fathers (Williams, 2007). The expansion of the Aristotelian corpus both stimulated and troubled Christian scholars. The focus on reason attracted intellectuals. However, propositions of Aristotle, such as the eternity of the universe, conflicted with accepted Christian theology. Scholars who attempted to incorporate Aristotelian ideas into contemporary philosophy sometimes found themselves in opposition to the Catholic Church. In 1277 the Bishop of Paris issued a condemnation of 219 propositions regarding the Faculty of Arts at the University of Paris. Primarily, theologians resented the Faculty of Arts teaching aspects of Aristotle s philosophy without any regard to how it might conflict with the accepted theology (Luscombe, 1997). For some time after the condemnation, intellectuals had to be circumspect about their use of Aristotelian philosophy. Nonetheless, the rediscovery of Aristotle s works left a lasting impression on philosophy, as it revolutionized the natural philosophy and theology of the middle ages. 8

9 Naturalism in Medieval Natural Philosophy The 12 th century development of naturalism in medieval natural philosophy came on the cusp of change. Just as Arabic scholarship and the revival of ancient Greek texts were beginning to filter into European scholarship, intellectuals began to reclaim the domain of reason implied in the logical works of Aristotle that had survived in the literature of the early Middle Ages. Medieval natural philosophy assumed the existence of God and that the universe was formed through an act of divine creation. Medieval naturalism did not challenge this assumption, but relegated God to the source of creation, not an active participant in it. The scholar Thierry of Chartes, in describing the creation story, limits God s role to just the first instant of creation. In that initial instant God created the four elements, earth, air, fire, and water. Everything else from that moment onwards just occurs through unfolding causation (Lindberg, 1992). Naturalism recognizes the existence of natural order, and philosophers espousing this belief looked for natural explanations for observed physical phenomena. Adam and Eve Lucas Cranach, _Cranach_d._%C3%84._001.jpg The 12 th century English scholar Adelard of Bath is notable both for his contribution to natural philosophy and as an Arabic translator. He contributed the first full Latin translation of Euclid s Elements and introduced trigonometry to Europe as transmitted through Arabic astronomical tables. In the preface of Questions Naturales Adelard refers to his travels to Antioch and attributes his ideas to Arabic learning (Burnett, 1998). The text is written in the form of a dialogue between Adelard and his nephew. His nephew puts forward a series of 76 questions regarding subjects in natural philosophy. The Questions Naturales covers subjects such as plants and animals, the four elements, the hydrological cycle, weather, and astronomy. The answers Adelard provides offer an intriguing insight into the state of knowledge at his time. What is particularly interesting about the work is its focus on reason, even to the exclusion of authority unless it is seen to be firmly based on reason. Early in the dialogue, when Adelard s nephew makes reference to God, Adelard replies, 9

10 I am not slighting God s role. For whatever exists is from him and through him. Nevertheless, that dependence [on God] is not [to be taken] in blanket fashion, without distinction. One should attend to this distinction, as far as human knowledge can go.... (Burnett, 1998) Throughout the rest of the work Adelard makes repeated reference to the use of reason. At then end of the dialogue Adelard s nephew brings up the role of God again, referring to God as an efficient cause. Adelard dismisses this as a discussion for another day. By this device, Adelard places supernatural explanations outside the realm of natural philosophy. Reason, not divine intervention, should be used to explain the material universe. Adelard s contemporary, William of Conches, wrote the Dramaticon Philosophy in a similar vein to Questions Naturales. This work takes the form of a dialogue between the Duke of Normandy and an unnamed philosopher. In a prior work, Philosophia, William offered some views that were challenged by the religious community. In the opening of Dramaticon Philosophy, William attempts to assure his audience of his Catholic orthodoxy. Still, he focuses on giving natural explanations. When the duke questions this approach, the philosopher s response is, What is more foolish than to assume that something exists simply because the Creator is able to make it? Does He make whatever he can? Therefore, whoever says that God makes anything contrary to nature should either see that it is so with his own eyes, or show the reason for its being so, or demonstrate the advantage of its being so (Ranca et al., 1997). The natural philosopher concedes God has the power to interfere with the natural order of things. But natural philosophy postulates a rational creator that does not intervene. In the tension that existed between reason, theology, and authority, medieval philosophers made explicit an assumption that had existed implicitly in natural philosophy; namely, that the universe is rational and intelligible to the human mind. This assumption, important for natural philosophy, is for science essential and foundational. Science is confined to commenting on the potentially explicable world, and relies on a continuity of causes and effects. If the world is inexplicable and continuity does not exist, science has little to offer in explanatory power. Natural Theology Church authorities were uneasy about some of Aristotle s works and suggested censoring passages of his text that conflicted with Christian theology. They were also uneasy with Arabic commentaries of Aristotle, such as those presented by Averroes, because they made no attempt to adapt the philosopher s ideas to Christianity. Despite the skepticism of some medieval thinkers that Aristotle could be reconciled to Christianity, natural theology sought to embrace Aristotelian philosophy. Thomas Aquinas, the foremost natural theologian, endeavored to compose a synthesis of Christian and Aristotelian philosophy in the mid 13 th century. Aquinas and John Duns Scotus, a Franciscan monk from the later part of the century, shared the belief that reason was sufficient to obtain at least a partial 10

11 knowledge of God by studying creation (Hall, 2007). As natural theologians Aquinas and Duns Scotus participated in a project set out by Anselm in the 11 th century of faith seeking reason. In Medieval scholastic philosophy one finds an earnest and diligent endeavor to explore and later to test the limits of reason. Subtleties and semantics of the medieval conversation may seem antiquated to a modern audience. Still, this exploration did much to shape our understanding of logic, philosophy, and reason to the present day (Rubenstein, 2003). Saint Thomas Aquinas, the most famous classical proponent of natural theology Thomas Aquinas s work made use of Aristotelian syllogism as a scientific method (in the medieval sense) for obtaining knowledge. Syllogism is a form of deductive reasoning composed of a general statement, a second more precise statement, and a third necessary conclusion to be drawn from the proceeding statements. A syllogism takes the following oft cited form: All men are mortal. Socrates is a man. Socrates is mortal. Aquinas sought to scientifically demonstrate the existence of God by reasoning through 5 ways. The 5 ways were built on observations regarding: motion, efficient causes of motion, the existence of entities, varying degrees of perfection, and the activity of unintelligent entities (Hall, 2007). The importance of Aquinas s work does not lie in building an argument that would be satisfying to modern scientific sensibilities. What matters is the approach Aquinas took and how the work of subsequent philosophers built on it or worked to refute his reasoning. Aquinas used a form of medieval argument known as scholasticism. The scholastic approach involves first stating the arguments against, then for, the side a person wishes to defend. It is not enough just to point out the strength of the arguments for a given opinion, but to also point out the weaknesses for the other side (Williams, 2007). Aquinas integrated this approach to the examination of Aristotelian ideas. Through the work of Aquinas and his successors, scholasticism became synomous with Aristotelian philosophy. It was through the scholastic philosophers that Aristotelian ideas became reincorporated in the western intellectual tradition. In Aquinas s lifetime, he was just one voice trying to define how Aristotle s ideas should be approached. Conservative thinkers were hostile to Aristotle s work and wished to suppress it. More radical thinkers, such as members of the Faculty of Arts from the University of Paris, enthusiastically embraced Aristotle, and taught his ideas without critique or 11

12 regard to their impact on theological ideas (Rubenstein, 2003). Aquinas sought to marry Aristotelian ideas to Christian theology. He started from a similar position to those stated by naturalism the century before, that God did not violate natural law. He accepted Aristotle s view that human knowledge is acquired through sensory experience. While he believed that some aspects of reality are not accessible to rational thought, overall, he exhibited considerable confidence in the ability of reason to describe natural events and even come to an understanding of God. In his own time Aquinas was censured by the conservatives and ridiculed by the radicals. A few years after Aquinas s death, when the Bishop of Paris issued the Condemnation of 1277 against Paris s Faculty of Arts, some of Aquinas s own ideas were included in the 219 condemned propositions (Luscombe, 1997). However, Aquinas s ideas had an enduring quality. Much of the scholastic philosophy that came after Aquinas either attempted to refine his ideas or tried to refute them. One of the philosophers who would attempt to refine Aquinas s work was John Duns Scotus. Scotus came to maturity after the Condemnation of 1277, and so encountered a more theologically conservative environment than Aquinas. This perhaps diminished his confidence in the capacity of experience to obtain scientific certainty. Scotus also felt that Aquinas had potentially limited God s role too much by claiming that God didn t interfere with the rules of nature. He argued that God could do, and might well do, anything short of behaving in a logically impossible way. Still, Scotus rejected Henry of Ghent s theory that only divine illumination could lead to certainty (Hall, 2007). It may seem counterintuitive that the philosophy of science could be advanced by an argument that asserted God s omnipotence. But Duns Scotus s logic led him in a direction that did just that. As a result of his assertion, he came to the conclusion that the laws of nature were only probable, not certain (Rubenstein, 2003). Additionally, he introduced the idea of falsification in his theology by arguing that some ideas about God could not be proved, but that they also could not be falsified (Hall, 2007). Furthermore, Duns Scotus argued for ontological parsimony. This idea, often identified as Ockham s Razor, looked to create explanations that involved the least number of steps possible. Although the idea of parsimony is currently associated with William of Ockham, it surfaced in the writings of a number of medieval thinkers before Ockham s time (Thornburn, 1918). Whatever the specific origins, it is an idea that flourished in the Middle Ages. 12

13 Roger Bacon and 13 th Century Natural Philosophy Statue of Roger Bacon in the Oxford University Museum Natural philosophy flourished during the 13 th century. The work of scholars such Albertus Magnus, Robert Grosseteste, and Roger Bacon exemplify what the century had to offer. As knowledge of Arabic natural philosophy increased, it encouraged advances in European scholarship in areas such as mathematics, astronomy, and chemistry in the form of alchemy. Natural philosophy continued in the vein of naturalism, looking for rational explanations for natural phenomena and challenging authoritative texts. Natural philosophers began the process of integrating mathematics into the study of nature. They relied less on deductive reasoning alone, looking to experience (personal observation or accounts of personal observation) and even conducting limited experimentation to verify results of reasoning. Inventions such as eyeglasses and gunpowder occurred some time around the 13 th century. The English Bishop Robert Grosseteste made wide ranging contributions to 13 th century intellectual life. He wrote works on theology, philosophy, nature, and translated and commentated on Greek texts. In Grosseteste s works one can find the medieval preoccupation with light. (Light was interpreted as a very literal metaphor for truth. Few scholars who studied natural philosophy of the time could resist putting forward ideas concerning optics and vision.) Grosseteste believed light played an important role in the creation of the universe and heavenly motions, and aided in understanding God. Aside from his preoccupation with light, Grosseteste advocated the value of observation, and at least in one case, experimentation. He argued for a form of parsimony in natural events: every operation of nature occurs in the most finite, ordered, shortest and best way possible for it (SEP, 2007). And he applied geometry to the understanding of natural philosophy. Albertus Magnus, another bishop with broadly ranging interests, also worked as a commentator on Greek philosophy, a theologian, a philosopher, and a naturalist. He is best known as the teacher of Thomas Aquinas. Albertus dabbled in alchemy, astrology, and botany. Most of his writings concentrated on the commentary of Aristotle, but within these commentaries he inserted sections regarding his travels and observations of natural philosophy. In his book De vegetabilibus he works carefully on the classification and description of plants (Durant, 1950). Medieval natural philosophy reached its apex in the work of Roger Bacon. He was a student of Grosseteste and an admirer of Albertus Magnus. Some enthusiasts go so far as 13

14 identifying Bacon as the first scientist in the modern sense of the term. Bacon acquired knowledge where ever he could find it. His linguistic expertise encompassed Hebrew, Greek, Arabic as well as Latin. He argued that knowledge of all of these languages was important for the study of theology and natural philosophy. The best known work associated with Roger Bacon is the Opus Majus. Bacon wrote the Opus Majus in response to a request from the pope for a copy of his work. Bacon composed the Opus Majus in a year, an impressive feat considering the text was over 800 pages long. Roger Bacon only intended this work as a summary. He hoped to obtain papal support for a program of research to produce a larger work in natural philosophy. The pope died not long after Bacon sent the work, and there is no indication that he ever read it before his death. Bacon never received a response to his effort. The Opus Majus contains seven treatises: on ignorance of error, the relations between philosophy and theology, the studies of foreign languages, the usefulness of mathematics, perspective and optics, experimental science, and moral philosophy. As supplements and summary to the Opus Majus Bacon also wrote two additional manuscripts, the Opus minus and the Opus tertium. In a biography of Roger Bacon, Brian Clegg (2003) claims that Bacon s work demonstrates, a basis of mathematics, an openness of mind, the desire to communicate, and the fundamental contribution of experiment. On this basis Clegg argues that Bacon was the first scientist. However, while Bacon advocated and even performed experiments, his focus was philosophical in nature. Moreover, individual scientists may make profound, unique contributions to theory and practice, but science thrives in a community environment. Functionally, it is hard to assign Bacon the role of scientist with no scientific community with which to interact. It may be more accurate to identify Bacon in the role of visionary. But by the 13 th century, particularly in the works of Roger Bacon, the philosophical underpinnings of science appear to have coalesced. William of Ockham Through the majority of the Middle Ages theologians and other intellectuals generally took for granted the idea that theology and philosophy were inherently compatible pursuits. Not until William of Ockham was that assumption to be seriously challenged. Though a deeply convicted theist, and an acute philosopher, Ockham held reservations on the capacity of philosophy to address the needs of theology. 14

15 William of Ockham was a student of Duns Scotus s philosophy. However, Ockham was skeptical about the efficacy of natural theology, and came to the conclusion that its arguments failed to prove what they claimed (Williams, 2007). He dismissed assumptions made by natural theologians such as the idea of an unmoved mover. Ockham challenged the idea that theology could be a science, since its first principles were not self evident. Consequently, theology and philosophy were not even the same kind of knowledge. Ockham believed that reason had limits; a person could reason from the best possible information available and still come to the wrong conclusions. Because reason and theology functioned differently, it was not necessary to try to reconcile them (Rubenstein, 2003). This position reiterates Dun Scotus s view that our William of Ockham ssor.com/philosophers/willi am-of-ockham.php understanding of the physical world is only probable, not certain. Like Scotus, Ockham also advocated ontological parsimony. The way that Ockham and Scotus used parsimony was more semantic and metaphysical than the way modern scientists use it. Ockham set out to reduce metaphysics to the least number of entities possible. Where Aristotle saw ten categories of being, Ockham identified only two, substance and quality. According to Ockham s philosophy, it was possible that there were more entities than were logically necessary, but human reason could only defend the necessary, not the possible. While most medieval philosophers believed in universals, Ockham held a nominalistic position. He argued that reality consisted of particular experience, and from particular experience we can make generalizations. Opponents of Ockham s nominalism objected on the grounds that without universals, there was no objective reality, and the world is potentially unintelligible (Williams, 2007). Though Ockham was less confident in the ability of reason to lead to knowledge of God, he believed that there was a place for both faith and reason within the human experience. By separating theology and philosophy, Ockham freed up natural philosophy from the need to conform to accepted religious beliefs. The parsimony espoused by Ockham and other medieval thinkers lead to an important methodological approach currently used in many scientific disciplines. The work of the scholastic philosophers helped integrate Aristotelian thinking into western thought. It is through the mediation of medieval philosophy and interpretation that modern thinkers view Aristotelian ideas. Though many aspects of medieval and Aristotelian thinking were eventually rejected by later thinkers, the legacy of the Middle Ages offered many useful tools for the engagement of modern science. 15

16 The Medieval Inheritance of Modern Science The medieval mind focused on questions that only sometimes resemble modern questions. Some of the abandoned questions seem trivial, based on misconception, or for some other reason no longer relevant to present culture. In other instances, the questions and answers are already imbedded in current culture and thought and grow increasingly invisible. (For instance, modern scientists frequently privilege an experimental approach to testing the ideas of scientific hypothesis. However, if the approach should violate the rules of basic Aristotelian reasoning, it s unlikely that a resulting paper would pass peer review.) The more profoundly ingrained a concept, the less consciously a culture acknowledges its meaning and consequence. With over half a millennia to absorb or reject the intellectual contribution of the Middle Ages, it is hardly surprising that the nature of this contribution has become obscured over time. The path between medieval philosophy and modern science is further convoluted because of the medieval lack of philosophical and disciplinary boundaries by which we now define the sciences. In order to obtain a just understanding of the medieval contribution, one must transgress the modern boundaries, even to the realm of theology. Science is ultimately a historical and cultural endeavor. The questions scientists choose to pursue are grounded in values and assumptions of the culture in which a scientist participates. We may take for granted the scientific focus of our own time, but the study of science in historical context emphasizes how cultural mores can influence the pursuit of knowledge. For instance, in the Middle Ages light served as an important theological metaphor. Consequently, natural philosophers exhibited a profound interest in optics and vision. As a result, some of the most modernly coherent medieval natural philosophy focuses on optics (Durant, 1950). Science may advance even under the influence of false assumptions. In The Structure of Scientific Revolutions Thomas Kuhn (1996) used the Ptolemaic system as an example of a now discarded scientific paradigm. Kuhn argued that paradigms last as long as they remain sufficiently functional for the cultures that use them. In Ptolemy s cosmology the sun, moon, planets, and fixed stars rotated around an unmoving earth. This theory was put forward in the second century BC. Not until Copernicus in the 15 th did the first serious challenge arise against the Ptolemaic paradigm. This was not because no one ever offered alternative opinions to Ptolemy, however. The century before Ptolemy, Aristarchus proposed a heliocentric cosmology. During the Middle Ages two Arabic astronomers raised issues concerning the Ptolemaic system. Abu Ishaq al-bitruji criticized the epicycles and eccentrics required to explain the movement of the stars. Abu al-rayhan Muhammad ibn Ahmad al-biruni suggested that astronomic data could be explained by a daily rotation of the earth on its axis and an annual rotation around the sun (Durant, 1950). Still, Ptolemaic astronomy was sufficient for the needs of the time. Astronomy did not stagnate for the 16 intervening centauries. Arabic scholars improved on the astronomy that they borrowed from the Greeks. When Arabic astronomy was transmitted to 16

17 Europe, European scholars continued the work. It was the accumulation of this astronomic knowledge that paved the way to the Copernican revolution. The Arabic science of alchemy was based on premises that have long since been abandoned. Still, working under these premises Arabic and European scholars experimented and obtained a useful working knowledge of chemistry. It helped contribute to a knowledge base from which the modern discipline of chemistry was eventually shaped. Much of the intellectual legacy that Medieval Europe passed on to posterity was not wholly original to the time or place. The historical periods of greatest intellectual vitality, both in Arabic and European scholarship, came with exposure to literature of ancient Greece. This exposure to an alien culture brought about the absorption of new ideas and resulted in intensely creative response to the new concepts and knowledge. Both cultures reformed and synthesized the products of philosophy to fit their own needs. It is through the filter of this synthesis that later generations have come to read classical literature. Important medieval approaches to the acquisition of knowledge have done much to influence how we approach science in modern times. Naturalism passes on an essential assumption to the project of scientific inquiry. In naturalism we assume a rational, lawful universe, without which there is no purpose in the pursuit of science, because if the universe is truly arbitrary it is also unintelligible. The scholasticism of theologians such as Aquinas, Duns Scotus, and Ockham provide some of the most precise and carefully honed examples of logical and metaphysical reasoning available from history. Both logic and metaphysics form an important foundation on which scientific methodology is built. While some Greek philosophers identified mathematics as the language of natural philosophy, it was medieval natural philosophers such as Roger Bacon who first truly began to integrate mathematics into disciplines such as physics. In a further move towards creating a more mathematical science, Duns Scotus and Ockham introduced the idea of applying probability to truth claims. In addition to theory, the Middle Ages introduced an important institution to modern times in the form of the university. The practice of science is profoundly influenced by this academic institution. In both theoretical and physical ways, the history of science would be profoundly different without the contribution of the Middle Ages. Towards the end of the Middle Ages the philosophical groundwork for the development of modern science had already been laid. Additional refinements were to be added over time, but all the essential building blocks were there. Yet, it was another several centuries until a truly modern science began to emerge. It is hard to define what exactly lead to this delay. Certainly, one factor occurred in the middle of the 14 th century, when Bubonic plague broke out. In less than a decade approximately a third of the population of Europe died. Successive, though less devastating outbreaks continued over the century that followed, further reducing the population. It was a difficult, demoralizing time and not conducive to further intellectual advances. Also, it was a time of transition, as the Middle Ages gave way to the Renaissance. The intellectual climate changed, and scholars began 17

18 shifting their focus to different types of questions (Williams, 2007). Many Renaissance scholars disdained the contributions of their medieval predecessors, even as they built new theories on the works of the prior age. For a long time the contribution of medieval philosophy was downplayed or even entirely ignored. Even today, the contributions of the Renaissance and Scientific Revolution are easier to point to, as the works of Galileo, Descarte, Sir Francis Bacon, Newton, Hook and Boyle are more tangible. But without the foundation provided by medieval natural philosophy, it is doubtful that these later contributors could have offered as much as they did to future generations. References Burnett, Charles, ed. (1998) Adelard of Bath Conversations with His Nephew, Cambridge University Press, Cambridge. Clegg, Brian. (2003) The First Scientist: a Life of Roger Bacon, Carroll & Graf Publishers, New York. Durant, Will. (1950) The Age of Faith, Simon and Schuster, New York. Hall, Alexander. (2007) Thomas Aquinas and John Duns Scotus: Natural Theology in the High Middle Ages, Biddles Ltd. Kings Lynn, Norfolk. Kuhn, Thomas. (1996) The Structure of Scientific Revolutions, 3 rd Edition, The University of Chicago Press, Chicago. Lindberg, David. (1992) The Beginnings of Western Science, The University of Chicago Press, Chicago. Luscombe, David. (1997) Medieval Thought, Oxford University Press, London. Ranca, Italo and Matthew Curr eds. (1997) A Dialogue on Natural Philosophy, The University of Notre Dame Press, Notre Dame. Rubenstein, Richard. (2003) Aristotle s Children: How Christians, Muslims, and Jews Rediscovered Ancient Wisdom and Illuminated the Dark Ages, Harcourt, Orlando. Standford University. (2007) Robert Grosseteste in Standford Encyclopedia of Philosophy. Thornburn, William. (1918) The Myth of Ockham s Razor in Mind, 27, Williams, Thomas. (2007) Reason and Faith: Philosophy in the Middle Ages, The Teaching Company, Chantilly. 18