Lesson 5: The Thirteenth Century
The rise of the university -- When we read John of Salisbury's description of 12th-century Paris we are given a picture of a very lively and various intellectual scene. On the left bank of the Seine any number of masters and students were clustered in different institutions. This was called the Latin Quarter because that was the language of scholarship, and the international body of masters and students communicated in it as well. There were schools situated at the monastery of St. Victor and on Mont Ste.-Genevieve. There was as well the cathedral school of Notre Dame located on the Ile de la Cité. At the beginning of the 13th century, for a number of reasons, many of them entirely non-academic, the masters and students of Paris formed into a legal entity called universitas magistrorum et scholarum.
The university thus was a natural outgrowth of the liberal arts schools and the theology schools already in existence. By unifying, the masters came under the chancellor of the diocese, and they initiated a graded apprenticeship whereby students could become full members of the guild: the courses to be taken, the writing to be done, the public manifestation of one's competence -- features that have descended to present day institutions had their rise in Paris.
There were several faculties making up the university. The Faculty of Arts was entered by boys in their early teens and led after some eight or nine years to their recognition as having mastered the arts -- Magister artium. This degree equipped them for possible entry into other faculties -- theology, law, medicine. If a Master of Arts began the study of theology in his early twenties, he could expect to finish the course in his early thirties.
Aristotle's second coming -- We have seen that some logical works of Aristotle had figured in the arts curriculum from the beginning, thanks to the translations by Boethius. Late in the 12th century, a translation of Aristotle's Nicomachean Ethics appeared in Latin. And then the flood began. At such centers as Toledo -- remember that Peter the Venerable had visited there to commission a translation of the Koran into Latin -- Christian, Muslim and Jewish scholars got together and began to put texts of Aristotle into Latin. Aristotle's text had mysteriously disappeared, been resurrected and edited, and then, thanks to translations into Syrian and then into Arabic, exercised an influence in the Muslim world. Spain was where Islam, having been driven back from France, now coexisted in uneasy truce with Christendom. However unstable the political conditions, scholars came into contact with one another, the vast treasury house of Greek learning that existed in Arabic excited interest, and the translations began, often under the patronage of the bishop, as at Toledo. Within a relatively short time, a quarter century, the traditional notion that the seven liberal arts adequately summed up secular learning was, as they say, blown out of the water. These texts arrived in Paris just as the educational system was being reorganized, and of course they influenced the new organization.
In the Faculty of Arts -- whose title indicates its continuity with the earlier situation -- philosophy would soon include such works as Aristotle's Ethics, Physics, Metaphysics, On the Soul, and many, many more. Moreover, these translations were accompanied by translations of Islamic scholars who had pored over them, figures whose names would be latinized to Avicenna and Averroes. What this meant was that the tradition of complementarity between secular and sacred learning had to be rethought. And for some, the arrival of Aristotle threatened not only the traditional curriculum, but the faith as well. If Aristotle taught things in conflict with the faith, he could hardly be thought of as complementary to it.
The mendicant orders -- When St. Francis of Assisi founded his order and St. Dominic founded his, they were at once a rebuke to the clergy of the time and men with a special mission. The Franciscans set out to live the vows of religion unequivocally -- poverty, chastity, obedience -- but it was poverty that most characterized their lives. They were mendicants, beggars, who depended on the charity of others for their survival. Quarrels over how literally owning nothing was to be taken finally brought, under Bonaventure, an interpretation that ensured the continuance of the Franciscans. Domingo Guzman, appalled by heretical distortions of the faith, formed a band of preachers to counter them. This required an educated group, and early on Dominicans were a feature in Paris through their convent of Saint Jacques on the left bank. When some masters joined the Franciscan order, there were Franciscan masters as well.
The presence of mendicant masters did not sit well with the diocesan priests, or non-mendicant religious, masters. There were theological attacks on the very concept of the new orders and concerted efforts to keep them from becoming masters. These efforts failed, and brought little credit on those who fought the mendicants. In the end, the most famous masters of thirteenth century Paris were either Dominicans or Franciscans.
We have concentrated on Paris as the proto-university. Soon universities were scattered across the map of Europe; masters had gone from Paris to England, and Cambridge and Oxford were founded. The phenomenon continued into Scotland where St. Andrews was founded in 1412.
William of Auvergne (c. 1180-1249) -- A master of theology who eventually became bishop of Paris, William was a member of the papal commission appointed to study the works of Aristotle to see if they could become the basis for university teaching. How does William regard Aristotle? He seems to blend Aristotle with the Islamic interpreters whose commentaries accompanied the text into Latin. Thus, he criticizes the Neoplatonic emanationist theory of creation as if it were Aristotle's. Gerard of Cremona translated the so-called Liber de causis and called it a work of Aristotle's when it is actually comments on selected propositions of Proclus. William took it to be Aristotelian. This is not to say that all William's criticisms of Aristotle miss the mark.
Here is his procedure.  Is a doctrine in conflict with the faith? If it is it is false.  But he then goes on to argue that the philosophical doctrine is false or ill-founded. In the case of the teaching that there is only one human soul -- Avicenna's and Averroes' misreading of Aristotle -- William thought that steel and torment should also be used to counter it. William also takes up the question of the eternity of the world, something Aristotle did hold. His treatment of this is subtle and impressive. Indeed, William is a master of great talent and accomplishment whose discussions of Aristotle and Aristotle's errors give a good sense of the difficulties confronting any easy assimilation of the "new" philosophical writings.
Alexander of Hales (c. 1185-1245) -- An Englishman who became a master of arts at Paris and then master of theology, perhaps around 1220, he spent some time in his native land but returned to Paris in 1232 and joined the Franciscans in 1236. He is noteworthy as being the first master to employ the text of Peter Lombard's Sentences as the basis of his teaching. In explaining the text, Alexander uses Scripture and Augustine, but also Aristotle, and he is often seen as the first to pursue speculative theology with reference to Aristotle. And while tentative, he is sympathetic. Among his fateful interpretations was to apply the Aristotelian teaching on hylomorphism to the soul itself as if it had a matter and a form.
Robert Grosseteste (1175-1253) -- Robert gives us a sense of the reaction to Aristotle at Oxford. The eventual bishop of Lincoln is well versed in the writings of Aristotle, and drew nothing but praise from Roger Bacon, who held Parisian masters in contempt. Robert's works are noteworthy for the number of mathematical and scientific writings, and he developed what might be called a metaphysics of light as the first body out of which emerges everything else. He wrote treatises on the relation of God to creatures, asking if God is the form of all things, and on creation. There is a good deal of Augustine in Robert, and perhaps a tension between the Augustinian tradition and the emerging influence of Aristotle.
Albert the Great (1206-1280) -- A Bavarian by birth, Albert's career covers the most exciting and controversial years of the thirteenth century. After some study in Italy he joined the Dominicans in 1223 and was sent to the convent in Cologne. From 1228 to 1240 he taught in various German Dominican houses, but in 1140 he was sent to Paris where he studied for two years and then, from 1242 to 1248, occupied one of the two Dominican chairs. Then he was sent to Cologne to set up a Dominican studium generale, the equivalent of a university. He was provincial of his order in Germany for three years, taught again, and then was made bishop of Ratisbon in 1260, a post he resigned after two years and returned to teaching and writing, carrying on until his death in 1280.
Theologian as well as philosopher, Albert showed an experimental bit, often adding to an account of some physical claim "I have tested this" or "I have not tested this." His first writings were theological (On the nature of the good, Summa on Creatures, Exposition of Sentences of Peter Lombard). He went on to comment on the works of (pseudo-)Denis the Areopagite. His so-called Aristotelian period extends from 1254 to 1270. He produced paraphrases on the Aristotelian corpus as well as on Boethius. In narrating these works, Albert draws on other commentators, so 'paraphrase' seems inadequate to describe them. He does insist that what he is writing is not his own opinion, a demur that some have mistakenly taken to be true of all medieval commentaries. In the last decade of his life, Albert composed a Summa theologiae.
In his Summa, as in his commentary on Peter Lombard, Albert applies to theology as a science the methodology of Aristotle. For example, What kind of science is it? What is its subject matter? Is it wisdom as well as science? The subject of theology can be understood in various ways, he tells us. God is the subject of metaphysics as that about which knowledge is chiefly sought, but being is the subject in the sense of that whose properties and causes are sought. So too God is the subject of theology because knowledge of God is what is principally sought, but Christ and the Church, or the Incarnate Word and all the sacraments with which he perfects the Church, are its subject in the sense of that whose properties and causes are sought. That is, he says, the subject of theology is the work of reparation. But how do metaphysics and theology differ? Metaphysics is concerned with God insofar as he has the properties of the first being, insofar as he is the first being; God is the subject of theology insofar as he has the attributes which are attributed to him by faith. In metaphysics, God is known in terms of being and its properties because he is the first being, whereas in theology he is known as the subject of properties that have been revealed.
Albert's lengthy attention to the works of Aristotle did not prevent him from acquiring a predilection for aspects of Neoplatonism. He seems to have picked this up from the Arabic commentators he favored in his so-called paraphrases of Aristotle.
Roger Bacon (1219-1292) -- An Englishman who began his teaching career in the faculty of arts at Paris, he took pride in the number of times he commented on the works of Aristotle. In 1247 he returned to England, where, at Oxford, he came into contact with Robert Grosseteste and decided to devote himself to scientific studies. This involved a large dose of magic and astrology. He became a great critic of the academic world, particularly of theologians who knew no philosophy. In 1257 he joined the Franciscan Order. There followed a period of silence, but then Roger wrote the pope to ask for his patronage while he wrote a work on how education must be reformed. The result was the Opus majus, which was followed by the Opus minus and the Opus tertium. The pope received these in 1267, the year before he died. This venture put Roger under a cloud, and the Franciscans imprisoned him, for how long is unknown. In 1292 he wrote a Compendium of Theological Studies. He died that same year.
For all his quirky and cantankerous nature, Roger's critique of a bookish academe has merit. It may have been his personality rather than his ideas that led others to ignore him. The Opus majus was written swiftly but when Roger was at the height of his powers. It is a program for reform rather than a finished work. It begins with a discussion of the causes of human ignorance. They are four: subjection to unworthy authority; influence of habit; popular prejudice; and the false conceit of wisdom. A champion of Aristotle, Roger observes that on some points Aristotle can lead us astray. The greatest of the four, that from which Roger clearly thought he himself had suffered most, was popular prejudice. The great of yesterday have flaws that are clear to a youngster today; what is known is as nothing to what has yet to be learned. He tells the pope that it is not so much that what is being taught is false as that it is assumed that everything is already known. The search for truth has three paths: Scripture, canon law, and philosophy. But wisdom is one. Canon law and philosophy are articulations of what is contained in Scripture. This seems to mean that no truth can be incompatible with Scripture. He sides with Avicenna in taking Aristotle's agent intellect to be, not a faculty of the soul, but something divine and apart. Philosophers, like the prophets, were recipients of revelation. What then is the distinction between philosophy and theology? They are parts of a whole, and philosophy is meant to lead us to theology, but philosophy is not to be gotten through hastily. Bacon's conception of theology owes little to Aristotelian methodology: all human knowledge serves to illustrate the truths God has revealed in Scripture. Bacon's comparison of philosophy and theology is indistinct and blurred. This great sprawling work gives us a sense of Bacon's enthusiasms, not least of which is knowledge of languages, Greek and Hebrew. He then goes on to treat of mathematics, optics, and experimental science. Mathematics is the key to the other sciences. In order to understand Scripture, the spiritual meaning is gotten through the literal meaning, and mathematics is necessary to grasp the literal meaning of the text. The Opus majus culminates in a discussion of moral philosophy which has a threefold task: duties to God, duties to neighbor, duties to ourselves. This section most shows the influence of Aristotle, and it ends with a discussion of the sacraments, the Mass, and the Eucharist.
Roger Bacon is a kind of patron for the unclubbable academic, the man convinced everyone else is wasting his time and he alone pursuing the truth. But the Opus majus should not be seen as one of those mad works produced in solitude in which some wild-eyed would-be prophet offers a solution to the ills of the world. It is an authentic work of genius, a mixture of the traditional and innovative, opinionated, on the mark, off the mark, proof positive that common sources and points of reference did not end in uniformity of thought.
Saint Bonaventure (1217-1274) -- John Fidenza was born near Viterbo, studied the arts in Paris from 1236 to 1242 and in 1243 entered the Franciscan Order. He studied theology under Alexander of Hales, completed his studies in 1253, and then taught in the Franciscan house in Paris until 1257, when, along with Thomas Aquinas, he was reluctantly acknowledged as a university master. Some months later he was elected Master General of the Franciscan Order, but he continued to lecture and preach in Paris. He was named cardinal in 1273 and was attending the ecumenical council in Lyon when he died in 1274 at the age of fifty-seven.
Among his writings are his commentary on the Sentences of Peter Lombard, disputed questions on Christ's knowledge, the Trinity, and evangelical perfection. The Breviloquium has been called a resume of Bonaventure's commentary on Peter Lombard. Furthermore, he wrote On the reduction of the arts to theology and The mind's road to God. He also delivered famous series of sermons in Paris when he was head of his Order: on the ten commandments (1267), on the gifts of the Holy Spirit (1268) and on the work of the six days (1273). His misgivings about the influence of Aristotle is expressed in these sermons.
Bonaventure and Thomas Aquinas were near contemporaries, often in the same city, but they were not close friends. Nonetheless, they complement one another as the two greatest thinkers of the thirteenth century. There has been much controversy over what Bonaventure meant by philosophy as opposed to theology, and the debate is fueled by the fact that Bonaventure wrote only theological works. Is his philosophy contained in and inseparable from its theological setting, or can it be extracted and granted a separate status Bonaventure himself did not give it? Discussions of the nature of Christian Philosophy in the twentieth century often turn on that question. In his Sentences commentary, Bonaventure distinguished four kinds of knowledge: first, purely speculative knowledge founded on the principles of reason, which is the science of human philosophy; second, knowledge that is in the intellect insofar as it is inclined by appetite: when founded on faith such knowledge is the science of Sacred Scripture; third, knowledge which inclines to action, founded on the principles of natural law; fourth, knowledge founded on faith which has its source in grace: this is a gift of the Holy Spirit.
The first and third kinds would seem to be philosophy as distinct from theology, the second and fourth kinds. In both philosophy and theology, there is a distinction between theoretical and practical knowledge. Generally speaking, philosophy is based on the principles of reason and theology on principles of faith. In this same commentary, speaking of the subject of theology, Bonaventure distinguishes three senses of subject of science. That to which all else is referred as to its radical principle; that to which all else is referred as to an integral whole; that to which all else is referred as to a universal whole. Applied to grammar, these would be exemplified by the alphabet, by perfect and correct speech, and by articulated sound capable of signifying. In theology these three senses are represented by God, Christ, and by either sacrament or the credible. The comparison of philosophy and theology in Bonaventure can be summarized thus:
- Philosophy is based on principles of reason, theology on principles of faith.
- Philosophy sees things in an inborn light belonging to the nature of the rational creature; theology is dependent on an infused light, the gift of faith.
- The subject of philosophy is the naturally knowable; the subject of theology is the credible.
- Philosophy begins with creatures and arrives at knowledge of God as its term; theology begins with God and considered everything else in the light of what God was revealed about himself.
The reader of this commentary by Bonaventure is not prepared for the distinctively Bonaventurian style of the later works. While his views are distinctively his own, they are arrived at in precise scholastic way with reference to commonly agreed upon sources. This is helpful when we consider two distinctively Bonaventurian tenets. Is it possible to believe and know the same truth at the same time? Bonaventure answers in the affirmative. This may sound like claiming that we can see and not see the same object at the same time. In explaining his perhaps surprising contention, Bonaventure asks what the objects of belief and knowledge are and of kinds of knowledge. If we speak of the knowledge of the blessed, this excludes faith. But in this life, knowledge is arrived at by reasoning. Is such knowledge incompatible with faith? It seems so since in the one case one assents on the basis of an argument, and in the other on the basis of faith. Can one have knowledge on the basis of reasoning and faith about the same truth? An affirmative answer is based on the fact that, in this life, with respect to a truth common to knowledge and faith, reasoning grounds some evidence and certainty about divine things but is not in every way clear knowledge in this life. Well, what about the conclusion of a proof of God's existence? God exists. God is one. Can such truths be simultaneously known and believed? Bonaventure says yes and explains by saying that our knowledge of this existent one does not comprise the plurality of persons. It seems clear that what Bonaventure means is that the same truth, differently understood, can be the simultaneous object of faith and reason.
This suggests the weakness of philosophy with regard to its ultimate aim, knowledge of God. In his sermons on the work of the six days (Hexameron), Bonaventure expresses his misgivings about philosophy and provides us with a catalogue of philosophical errors: Philosophical teaching about virtue is unsatisfactory; it cannot heal our wayward affections. Moral philosophy fails to recognize man's true end, which is supernatural. It is not of course that philosophers failed to do what they could do, but that there is more than is dreamt of in philosophy. In speaking of creation, he stresses the need for Ideas, notes Aristotle's denial of them, and takes the definition of God as thought thinking itself in Metaphysics 12 to mean that God could not know particular things. This leads Aristotle to reject providence and to a fatalistic view of happenings in the world. The eternity of the world, that there is but one intellect for all men -- these too follow from rejection of the Ideas. Thus Bonaventure both opts for Platonism in its Augustinian form -- the Ideas are the divine exemplars of creatures -- and accepts the Averroistic and Avicennian interpretations of Aristotle as accurate. Of course it was the acceptance of these interpretations by masters of arts at Paris that precipitated the crisis to which Bonaventure is responding. Accepting these interpretations as accurate must then lead to putting Aristotle under a cloud.
In such works as The Mind's Road to God and Reduction of the arts to theology, Bonaventure provides a view of the whole in charged and mystical terms, so that the reader is carried along by a desire to share the vision of this learned and saintly man. His preference for Plato, as interpreted by Augustine, leads him to see Aristotle's account of intellectual knowledge as inadequate. Aristotle held that thanks to our agent intellect we are able to grasp or abstract from the sense image of things their nature or essence. But can knowledge of God be an abstractive knowledge? Better to think of it as the product of an illumination. Aristotle's account may work for knowledge of the things of our sense experience, but it will not do when it is a matter of the divine.
Bonaventure argues against Aristotle's claim that the world is eternal not by saying that by faith we know it is not eternal. This would simply mean that Aristotle did not have either faith or revelation. But does his contention make sense? Is it conceivable that the world has always existed? Bonaventure offers arguments to show that this is an incoherent claim. Thus Aristotle is wrong on philosophical grounds and not simply because faith gives an answer to the question that reason could not attain.
Bonaventure says much about philosophy, but only in the context of theological writings. He himself felt no impulse to engage in philosophical speculation as such. As for the "errors of Aristotle", despite the wide and deep acquaintance with Aristotle his commentary on the Sentences reveals, when controversy erupted between the arts masters and theologians, Bonaventure accepted the artists' understanding of Aristotle, derived from the Arabs, and inveighed against it. He does argue against these views but did not undertake the close reading of the text of Aristotle to appraise these views. But his argument against the eternity of the world is a philosophical argument and will be accepted or rejected on the bases Bonaventure provides for it.
It has been mentioned that Bonaventure died in 1274 while taking part in the council at Lyon. Thomas Aquinas was on his way to that same council when he fell ill and died. No wonder that Dante put the two men together in the Paradiso, in the circle of the sun. There are deep and undeniable differences between Bonaventure and Aquinas, but in many ways they are complementary, each man the greatest thinker produced by his respective order.
Saint Thomas Aquinas (1225-1274) -- It is not without reason that Thomas is looked upon as a culminating point of Christian and philosophical thought. For one thing, he gives us a clear distinction between philosophy and theology, one that is based first of all on the difference between their starting points or principles. Philosophy is natural reason at work and is discourse that takes its rise from principles within the grasp of any person with standard cognitive equipment. It is not that these principles are first articulated as quasi-axioms and then deductions made from them in the manner of Euclidean geometry. The kind of thinking that characterizes geometry has a datable beginning point in our lives; we may have the memory of first hearing or seeing the axioms formulated, the theorems stated and proofs constructed. But thinking is something we are engaged in from the dim origins of childhood and its principles seem rather to be discovered by driving discourse back to its fundamental assumptions. Thus there can be a sense of novelty when they are first formulated, but what is formulated has been operative in our thinking all along. "It is impossible for a thing to be and not to be at the same time and in the same respect." The first time we hear that it has the sound of a tongue-twister, yet it is latent in all our discourse. That something either is or is not is not something we derive from other knowledge; all our thinking presupposes and is dependent upon it. We do not learn it in any strong sense of learn -- deriving it from other more knowable and obvious things. Such principles are the presupposition of thinking and are definitive of philosophical discourse. Any philosophical claim has to be driven back to such common principles in order to gain our assent.
Theology presupposes faith, that is the acceptance of truth on the basis of a divine revelation. Methodologically it looks very similar to philosophy, but its characteristic arguments are driven back to truths of faith such that conclusions are true for one who holds the premises to be true. In that sense, theology unlike philosophy is "in-house" -- it works for those who have the gift of faith. Theology also uses truths of a natural sort, of course, but they do not characterize its discourse. The adage that philosophy is the handmaiden of theology means that theological discourse -- though not faith -- presupposes and puts to use truths gained by the use of natural reason. But the water of philosophy is changed into wine by this theological use of it. The very first article of the first question of the first part of the Summa theologiae asks if there is any need for a discipline beyond those which make up philosophy. Beginners in theology are supposed to have learned philosophy already, and the arrangement of the medieval university institutionalizes this. The faculty of arts must be passed through to get to the faculty of theology.
The division of philosophy -- We use our mind either simply to find out what is the case, to attain truth, or we use it to find truths which we can put to a use beyond mere knowing, that is, making or doing. The sciences based on the first use of our mind are called speculative sciences, those based on the second are called practical sciences. One speculative science is distinguished from others on the basis of its subject matter. To understand this we must recall the basic structure of discourse, the syllogism. A syllogism is discourse in which from the fact that certain things are true it follows that something else is true. In its simplest form this has the following look:
A is C
C is B
A is B.
C stands for the middle term which links A and B. In a science in the strongest sense, C is the definition of A, and B is a property of A which follows on its being what it is. This is formally true of any strong theoretical proof. But it is instantiated in different ways, and the difference between formally different sciences is seen in the mode of defining C. In natural science, definitions include sensible matter, that thanks to which things are subject to change. Since the definition is the definition of A, we say that different ways of defining the subject of the conclusion yield different kinds of science. The subject of the conclusion is the subject of the science. The definitions of mathematics do not include sensible matter, yet there are individuals of a type, e.g. many circles of the same diameter. Circle A does not differ from circle B in being a circle, so something like the discriminating accidents of material individuals is operative in mathematics. A third science called metaphysics does not include matter in either of these senses -- sensible or imaginative -- in its definitions. Natural science is concerned with being as changeable or mobile; mathematics is concerned with being as quantified; metaphysics is concerned with being as being.
The natural beginning of philosophy -- The activity of the human intellect presupposes the activities of the senses, external and internal. From the unified image of what is sensed, the mind grasps the nature common to many material individuals. This grasping is called abstraction because the formulation of what the nature is, its definition, does not include the peculiarities of this or that instance of it. What is peculiar to Peter or Paul is not mentioned in the definition of human nature which is common to them. It is not that the nature thus considered exists outside the mind as another sort of individual; it owes its unity to the mind, but that unity is possible because of the real similarity between individuals of the same kind. In living things this is due to the fact that some of them are parents of others who in turn become parents, and so on. The kin of kinds are kindred to them. We are not surprised when cats have kittens. Given the origin of our ideas and reasoning in our sense perception of material individuals, our thinking may seem limited to knowing the natures and properties and so on of material things. That this is not the case is something that has to be proved.
The structure of the natural things -- The things that we sense have come into being, change constantly in several ways while they endure, and eventually undergo that change after which they are no more. The account given above of abstraction might seem to suggest that the human mind right off the bat forms an idea of the specific nature of a range of individuals. Of course this is not so. Our first intellectual grasp of sensible things is wildly general: "it is something, a being." Further reflection leads on to the realization of different kinds of things, say, living and non-living; and some living things have senses and others do not, and those that do are divided between those that have reason and those that do not. In this step-wise fashion we move from general and confused -- many kinds are confused in one general grasp -- to more and more specific understanding of nature until we arrive at kinds that are no longer divisible into further kinds; we call them species.
Earlier, in treating of Parmenides, we saw the analysis that Aristotle gives of change and of the thing that is the result of change. Change minimally involves a subject and two contrary states of the subject. The product of change is the subject plus a characteristic: matter and form. This analysis is clear enough but it does not inform us of the different kinds of changeable things. Advance in natural philosophy is had by striving for more and more precise knowledge of things that come to be as the result of a change.
One of the marks of Thomas's philosophy, something he learned from Aristotle, is that the names of the elements of the original analysis are retained as knowledge progresses, with their meaning altering as progress is made, thus creating a chain of related but not identical meanings. Such a language is a powerful propaideutic device, a kind of Ariadne's thread we can follow backward when the forward progress grows confusing. Change, as Aristotle and Thomas first analyze it, is most obviously exemplified in a thing or substance's altering, or moving, or growing. But what about the change whereby the substance begins to be or ceases to be -- not begins to be white, or here, or tall, but begins to be sans phrase? If this is indeed a change it involves a subject, but the subject cannot be a thing, since then the change would be only incidental, the modification of an enduring thing of a given kind, and not the coming into being of the substance itself. Aristotle says that we discern the subject of such radical or substantial change on an analogy with the subject of incidental or accidental changes of substances. When he negates of that subject the notes of the subject of incidental change, he calls it prime matter. Of course this is not to prove that substantial changes occur. We already know that there are substances and that they come into being and pass away. We are accounting for what we already know, not deducing it.
This first extension of the meanings of matter and form inaugurates a procedure that continues throughout philosophy. The substantial form of the living will be differentiated from that of the non-living by calling it soul. It is thanks to soul that living things perform those activities we call vital -- moving themselves about, taking nourishment, sensing, desiring, and so on. These activities are related to the living thing, body and soul, as forms to matter. In speaking of perception, we analyze activities, operations, changes such as coming-to-see, coming-to-hear, coming-to-taste and the like. These changes are analyzed by asking how their elements are distinguished from the kinds of change already analyzed. Thus 'matter' and 'form' take on new but related meanings. When Thomas tells us that to know is to have the form of another as other, he invites us to distinguish between the way in which the apple becomes red and the way in which we come to see red. Seeing red is not productive of another instance of the kind.
As one looks back over the procedure of natural philosophy he will see key terms acquiring new and related meanings, the later ones quite distant from the earlier, but nonetheless related in such a way that the very procedure is illuminating. Aristotle will call such terms deliberately, as opposed to accidentally, equivocal terms; Thomas will call them analogous terms.
In the course of the study of nature, Aristotle fashioned two proofs that establish that natural things do not exhaust reality. That reality cannot consist of moved movers, but requires a first unmoved mover, points the mind beyond the physical realm, but it is the physical realm that provides the premises of the proof. So too the argument that human intellection involves a change that is not of itself a physical change grounds the realization that the human soul is not corruptible.
Metaphysics -- If to be and to be material are not identical, a science of being as such, being as being, as opposed to being as material, becomes a possibility. Mathematics is not that science since the way we define mathematicals does not commit us to the judgment that they exist as they are defined. In that sense, numbers and lines and figures are ideal entities. But the prime mover and the human soul have been shown to exist without matter.
When it is said that the subject of metaphysics is being as being and that a science seeks to know the properties of its subject, the project of metaphysics seems to put a premium on generality. But we have seen that progress in knowledge is from the general to the particular. Yet to know something as a being would seem to be the least particular and the most general thing that could be said of it. That is hardly an accomplishment. The metaphysical enterprise is best seen as the effort to gain less inadequate knowledge of immaterial being, pre-eminently of God, rather than common truths about everything in general. This is clear from its central move. Being is said in many ways but principally of substance, secondarily of the accidents of substance. This justifies concentrating on substance. But substance first means material substance. What the metaphysician then does is to reflect on the meaning of substance in this unarguable instance of it and note that in a substance composed of matter and form, form is what is "most substance" in it. This is the basis for speaking of immaterial substances and substances that are subsisting forms. The form of a natural thing does not subsist; the natural thing does. So "subsisting form", while it is a meaning of substance gleaned from an analysis of natural substance, does not apply to it. Nor of course does this analysis establish that there are any immaterial substances. The realization that there are immaterial existents comes prior to metaphysics. Metaphysics is the analysis of that realization and the fashioning of concepts and a language that will be less inadequate to such beings. This, again, demands the extension of names of natural things and a refinement of their meaning so they can be applied to immaterial things.
There can be any subsistent forms, so each of them exists to the extent of its nature or essence. Each is a kind of being. But whatever is a being of a kind has a nature distinct from its existence. This means that it is caused by another, since nothing can bring itself into existence. Here Thomas makes the ultimate metaphysical move to a description of God. If caused immaterial substances have a nature distinct from existence, God can be thought of as subsistent existence. This does not mean that he is featureless existence. Rather his existence is the fullness and summation of the perfections found in a diminished and participated form in his effects. Aristotle, in the Metaphysics, fashions a concept of God as subsistent thinking, moving from the most exalted activity in creatures to a way of thinking of it that requires distinguishing and separating it from everything in created thinking that makes it less than perfect.
Ethics and contemplation -- Speculative knowing culminates in metaphysics, in such knowledge as we can attain of God. Practical knowing can be exemplified by the know-how that goes into building a dog house as well as by the thinking that is embedded in our actions, our choices and decisions. The latter is called moral. The former aims at the perfection of the thing made; moral knowledge is concerned with the good or perfection of the agent as such.
Human actions are deliberate and voluntary. That is, we must both know and will what we are doing. Any defect in either of those elements opens the possibility that what seemed to be a voluntary act really was not. Not every activity of a human person is voluntary -- the circulation of the blood, respiration, digestion, fear and desire. Thomas reserves the term 'human actions' for voluntary and thus moral acts; the others he calls 'acts of a man.' Voluntary acts are undertaken for some end which is the fulfillment or good of the act. Since there are zillions of human acts, there are zillions of ends for which humans act. If we say the good is that which is aimed at by an act, it looks as if we cannot discriminate between good acts and bad. We can so discriminate, because while everyone acts for the good, desires what he desires under the aspect of good, it may be only apparently his good, so that to choose it is defective action. How can we tell which of the goods pursued are real goods and which only apparent?
If someone hits himself over the head with a hammer he is wrong to do so because his action implies that this is good for him. If he keeps it up he will crack his skull, fall unconscious, perhaps die. None of these things can be a fitting aim of an agent who seeks to do what is fulfilling of him, that is, what is really good or perfective of him. How can we develop the notion of the human good?
Practical knowledge, like speculative, begins with the comprehensive and inclusive. The human good is that which is our comprehensive good, not the good of our foot or earlobe or scalp, but our integral good. We begin by getting a purchase on this and then proceed to more informative guidance. Guidance, because the point of such discussions as these is not simply to get clear about what is the case, but to acquire knowledge that can guide our actions.
To ask what the human good is is unlike asking what the good of kangaroos or ground squirrels might be. So too, as the distinction between human acts and acts of man indicates, it is unlike asking what the good of those activities of ours that can be found in plants and squirrel and the like might be. If the good of an activity is success in achieving the end of that activity, we can say that the human good is the success or perfection of the distinctively human activity. This is not digesting or breathing and the like. It is rational activity. (We are back at the notion of voluntary acts). The good or perfection of rational activity will be the good of the human agent. Now it is not nothing to establish this, but immediately we are struck by the fact that 'rational activity' is of all kinds, and there does not seem to be a generic meaning we could give and then proceed to specific meanings. That is because 'rational activity' is analogously common to many things.
In the most obvious sense, rational activity is the activity of reason. But we can distinguish between the theoretical and the practical use of reason, and the good of the one is not the same as the good of the other. Furthermore, those desires and fears are common to men and animals; such emotions can come under the sway of reason and can then be called rational. We may desire or fear willy-nilly, but how we cope with such emotions is up to us: there is a human way of fearing (courage) and a human way of desiring (moderation). When the pursuit or avoidance of the objects of such spontaneous emotions is related to the overall good of the human agent, they become moral because rational.
The perfection of an activity is called its virtue. Therefore, since rational activity has many senses, there will be many senses of virtue. Virtue is that which makes an activity and an agent good. The good is the object of desire, and so it is that those instances of rational activity which involve will and appetite are called virtues in the strongest sense: the good they pursue is the overall good of the agent. The good of intellectual activities is the perfection of the mind, which is a good, but not the good of the whole individual -- that is why it too must come under a moral appraisal, not as to its inner workings, but as to its use. Thus the human good consists of a plurality of virtues which are virtues in an analogous sense.
Although the perfection of the mind is a virtue in a lesser sense, it is a more noble activity, and thus the perfection of intellect can be said to be the perfection of that which is highest in us. The philosophical life is the moral orientation of other activities to the end of intellect. Thus it is that Aristotle and Thomas can speak of contemplation of the truth, of God, as the ultimate end of the human agent. So it is that the aim of metaphysics, wisdom, knowledge of God, fuses with the end of the moral life. The culminating discussion of Aristotle's Ethics is theoria, contemplation.
Natural and supernatural end -- It is possible to formulate the human good or end simply in terms of what a human agent is. But through faith we know that we are called to an end which exceeds our nature, a supernatural end. Does the supernatural end cancel out and replace the natural end? From the point of view of the supernatural end -- eventual union with God in heaven -- the natural end is imperfect and this-worldly, but it relates to the supernatural, not as its opposite or contradictory, but as imperfect to perfect. It is subsumed into the moral life of the believer and for the non-believer will be the sole measure of action. Moral philosophy is not false, but its truths are, from the point of view of our supernatural end, inadequate. In much the same way, in the theoretical order, the truths that can be naturally known about God -- what Thomas calls the preambles of faith -- are not false but inadequate when compared to what God has revealed to us about himself, the mysteries of faith.
Thomas's adoption of Aristotle put him in bad odor with those who were rightly concerned about what masters in the faculty of arts were doing with Aristotle. The crisis of Latin Averroism arose essentially because some masters accepted the bad interpretations of Aristotle they found in Averroes. Thomas showed that the so-called "errors of Aristotle" were either misreadings of the text or views that could only be excluded by revelation, e.g. the eternity of the world. God could have created an eternal world, Thomas argued, and we know that he did not, not because of argument, but thanks to Genesis. Thomas's practice clearly implied that, correctly understood, Aristotle is by and large a massive achievement of natural reason and compatible with, indeed supportive of, the faith. This was not arrived at by twisting the text of Aristotle but by reading it carefully. Toward the end of his life, in response to this crisis, Thomas wrote word-by-word commentaries on a dozen works of Aristotle. These enable anyone to determine the value of his readings of Aristotle's texts.
Compare Bonaventure and Aquinas on Aristotle. No more than five pages.