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The Mind's Road To God

St. Bonaventure


There should be little need of apologizing for a new translation into English of Saint Bonaventura's "Itinerarium Mentis ad Deum," for it has been recognized by all serious historians of philosophy as one of the shorter masterpieces of medieval philosophy. It sets forth in very few pages a whole system of metaphysics; it illustrates a philosophical method; it typifies the thinking of one of the great monastic orders of the West; it stands at the beginning of Renaissance science as one of those documents in which the future can be seen in germ. Besides its importance as an outstanding work in metaphysics, a work comparable to Descartes' "Discourse on Method," Leibniz's Monadology, or Hume's "Enquiry" in its compactness and suggestiveness, it represents a strain of medieval thought which has been too much neglected since the publication of "Aeterni Patris," in 1879. That encyclical with its emphasis upon Thomism has given many people, both Catholic and non-Catholic, the impression that the philosophy of Saint Thomas Aquinas is the "official" philosophy of the Roman Catholic Church. The result of this miscomprehension has been disparagement of writings other than Thomistic. Yet even in the thirteenth century Catholic philosophers were far from being in agreement, either on matters of doctrine or method. One has only to mention such figures as Alexander of Hales, the master of Saint Bonaventura; Roger Bacon; and the various monks of Saint Victor, to realize that the confusion and disagreement which certain writers of today find in our own time were just as characteristic of a period to which they refer as one of universal concord.

The metaphysical point of view of Saint Bonaventura can be traced back to Plotinus, if not to Philo. Fundamental to his whole system is that fusion of the three hierarchies of Neo-Platonism: the hierarchy of logical classes, that of values, and that of reality. Elementary students of logic are accustomed to the doctrine that individuals can be grouped into classes which belong to certain species; that these species are again susceptible to classification in certain genera; that these are capable of being grouped into still larger orders and families, until we come to the class which includes all other classes and which is usually called being. This hierarchy of classes in the textbooks of classical logic is called the Tree of Porphyry. In non-philosophic work we find the same sort of thing illustrated in the Linnaean classification of plants and animals. The higher up one goes in this hierarchy, the more inclusive are one's classes. Thus the class of vertebrates is more inclusive than the class of mammals, and the class of animals is more inclusive than the class of vertebrates.

If we assume, as most classical writers did, that such a classification reproduces the structure of reality, that classes are ordained by God and are not simply convenient groupings made by man for his own purposes, then we can see in this order of beings a scale of creatures which might be thought of as a map of all things, a tree not only of life but of all existence. But an added assumption is usually introduced into the discussion at this point, the assumption of both Plotinus and Saint Bonaventura, that the more general a class, the more real and the better. This assumption may be argued, but one can at least imagine why someone contemplating this arrangement of classes within other classes,

running from the least inclusive to the most inclusive, would maintain that there was logical priority in the more general. For before one can define, let us say, man as a rational animal, it would be necessary to know the definition of "animal"; and before one could define "animality," one would have to know the definition of "living matter." This logical order of priority and posteriority might be thought of as corresponding in some mysterious way--and it has remained mysterious to this day--to some relationship in the order of reality. The problem was to discover precisely what this relationship was.

Plotinus answered the question by the invention of a basic metaphor. The universe was subject to something which he called "emanation." The lower classes flowed out of the upper classes as light flowed from a candle. Such metaphors have been of the greatest influence in the history of thought, both philosophic and scientific. Thus we have had such figurative terms as "affinity" in chemistry, or the "life force" in biology, or the "life cycle of a nation" in history, terms which were taken literally by some people but which upon scrutiny turned out to be figures of speech. In Plotinus' case there is little doubt that he believed emanation to be literal truth; though when he came to explain how lower orders emanated from higher, he could do it only by means of a more elaborate figure of speech or by having recourse to what he thought of as a law of nature, namely, that all things produced something and that what they produced was always "lower" than they themselves. Thus, Being produced the kinds of Being, and each kind produced less inclusive kinds; and so on down to the smallest classes in which individual things were comprised.

This hierarchy of Being appears throughout the work of Saint Bonaventura, though he did not derive it immediately from Plotinus. It had become a medieval commonplace which few were willing to question. And yet he could not accept the whole theory of emanation, since he was bound by his religious faith to believe in actual creation out of nothing. The God of Plotinus was The One from whom everything flowed like light; the God of Saint Bonaventura was the personal God of Genesis. His metaphysical problem was to accommodate one to the other. This accommodation appears most clearly in the fifth chapter of the "Itinerarium."

The second hierarchy which was fused with the logical hierarchy was that of value. There is no purely logical reason why the general should be any better than the particular, though there are good traditional grounds for thinking so. Plato, Aristotle, the Neo-Platonists, and even the Stoics had a tendency to confuse goodness with the ideal or the general. In ancient Pagan thought, there was a standard belief that no particular was ever a perfect exemplification of its class--no triangle made of matter being a perfect geometrical triangle, no human being a perfectly rational animal, no work of art a perfect realization of the artist's idea. Arguing in this way, one could see that no species would ever perfectly exemplify its genus, no genus its higher order, and so on. Hence the process "downward" from Being was degeneration. When one stops to think that the Christian religion insisted upon man's nature as having been vitiated by sin--sin which, though committed by our primordial parents, was nevertheless inherited by us--one can also see why, to a Christian, the fusion of the logical and the value-hierarchy was natural enough. We still look in vain for the perfect exemplification of animal and vegetable species, though we are inclined to believe that the species is an ideal formed for intellectual purposes, and not to be expected to exist in anything other than scientific books and articles. But to a Christian thinker of the type of Saint Bonaventura, the species and genera were the ideas of God in accordance with which He had created the world. It is they which are responsible for the orderliness of the universe; they are sometimes called by the Stoic term, seminal reasons. In the nineteenth century, when men were as impressed by the regularity of scientific laws as they had been in the thirteenth, people like Lord Russell found a religious satisfaction in contemplating them, the only difference being that Lord Russell did not use the Stoic term; nor did he think of scientific laws as the ideas in the mind of God. If permanence and invariability are marks of goodness, then indeed the more general the law, or the more inclusive the idea, the better. And since the most general and inclusive term is without question the term "Being," it would follow that "Being" was the best of all things. In the sixth chapter of the "Itinerarium," in which Saint Bonaventura discusses "Good" as the name of God, the importance of this fusion appears most clearly.

The third hierarchy, as we have said, was that of reality. In common speech we are accustomed to think of particular things in this material world of time and space as more real than ideas, or logical classes, or mathematical concepts, such as circles and triangles. We should, if untutored in the history of philosophy, think that a given man, George Washington or Abraham Lincoln, was more real than the idea of mankind though it is doubtful whether we should proceed to maintain that the idea of "rational animal" is more real than that of "animal." The fundamental question for a philosopher is what we mean by the adjective "real" and whether we should give it a meaning such that it may be used in the comparative and superlative degrees. Saint Bonaventura was far from being unique in thinking that this adjective was comparable; indeed such modern thinkers as Hegel and his followers seemed to have taken that for granted. In any event Saint Bonaventura did believe in its comparability, and he identified the hierarchy of reality with those of logic and value.

This fusion of hierarchies lies behind the whole method of thinking which is illustrated by the "Itinerarium," and it must be accepted by a reader who wishes to study the work sympathetically. But along with this metaphysical matrix a certain philosophical method is to be found which is of particular importance in studying this work. That method is resident in a theory of knowledge which makes true knowledge a matter of inspection, of seeing. We all have to believe that certain ideas must be taken for granted, whether they are the postulates of a system of geometry which we accept merely for the purpose of deducing their consequences or whether they are the simple matters of perceptual fact which we are likely to call the truths of observation. Again, when we deduce a conclusion from a set of premises, as in a simple syllogism or a bit of arithmetical reasoning, how do we know that the conclusion is not merely logically entailed in the premises, but true also to fact? Cardinal Newman, in his "Grammar of Assent," distinguished between what he called "real assent" and "notional assent"--the former being the assent which we give to propositions of existence or, roughly, fact; the latter, that which we give to the logical conclusions. Thus the following syllogism is logically accurate, but no one would believe in the truth of its conclusion:

1. All triangles are plane figures.

2. John Doe is a triangle.

3. John Doe is a plane figure.

We should be obligated to maintain that the conclusion followed from the premises, but we would not give real assent to it nevertheless. Just what do we mean by real assent, and how does it arise?

The most obvious case of real assent occurs in the acceptance of the truths of observation. If someone is asked why he thinks sugar is sweet, he will tell you that it is because he has tasted it. If someone asks why a person believes that the sky is blue, he will be told that the person has looked and seen. Sensory observation looks like simple and direct and incontrovertible knowledge. It is not quite so simple and direct and Incontrovertible as used to be thought, but we are dealing with the common-sense point of view here, and from that it has all these traits. Throughout the "Itinerarium" Saint Bonaventura emphasizes that knowledge in the last analysis comes down to seeing, to contemplation, to a kind of experience in which we know certain things to be true without further argument or demonstration. On the lowest level, this occurs in sensory observation, on the highest in the mystic vision.

Along with this insistence on direct experience as the source of all truth runs a practice which goes back at least to Philo-Judaeus in the Hebraic-Christian tradition: the practice of the allegorical method. In Philo, who was mainly interested in the Pentateuch, the allegorical method was employed in interpreting Scripture. It was believed by him that if every verse in the Bible was accepted literally, then we should have to believe things which were contrary to reason. Thus we should have to believe that God, Who is not in space, actually walked in the Garden of Eden; that He spoke as human beings speak with a physical voice; that He literally breathed into Adam the breath of life as we breathe our breath into things.[1] But to hold such beliefs is to deny the spirituality and ubiquity of God, and that is repugnant to our religious and philosophical theories. Consequently Philo maintained that these and similar texts must be interpreted allegorically, and he naturally believed that he had the key to the allegory. Similarly the "Itinerarium," which begins as a meditation upon the vision which Saint Francis had on Mount Alverna, continues as an interpretation in philosophical terms, not only of the vision itself, but also of certain passages in Exodus and Isaiah in which details of the vision are paralleled. The Seraph which Saint Francis saw, and which had three pairs of wings, has to be interpreted as a symbol of a philosophical and religious idea. The wings become stages in the process of the mind's elevation to God, and their position on the body of the Seraph indicates the heights of the stages. Furthermore, it will be seen that even the physical world itself becomes a sort of symbol of religious ideas. This was in keeping with many traditions which were common in the Middle Ages--ideas that appeared in the Bestiaries and Lapidaries, and which we retain in weakened form in some of our pseudoheraldic symbols, such as the Eagle, the Lion, and the Olive Branch; or the use of certain colors, such as blue for hope, white for purity, red for passion. Among these more popular symbols was that of the macrocosm and the microcosm, according to which a human being exactly mirrored the universe as a whole, so that one could pass from one to the other and find corresponding parts and functions. Much of this was undoubtedly fortified by Saint Francis' fashion of humanizing natural objects--the sun, the birds, the rain, and so on--in his talks and poems. Few, if any, of the saints seem to have felt such an intimate relationship with the physical world as the founder of the Order to which Saint Bonaventura belonged.

The full effect of this appears in the first chapter of the "Itinerarium," in which we are told that God may be seen in His traces in the physical world. This is the basis of what sometimes is called natural theology; for if we can actually see the traces of God about us in the order of natural law, then we have a start toward knowledge of the divine mind which is sure. It is only a start, Saint Bonaventura maintains, but it is the proper start. It means that one does not have to be a great rationalist, an erudite theologian, a doctor, to know religious truths. One has only to look about one and observe that certain laws obtain; that there is order; that all things are "disposed in weight, number, and measure." This can be seen; and when it is seen, one has a reflection of the divine mind in one's sensory experience. One has only to contrast this with the method of Saint Thomas Aquinas in the "Summa Theologica," in which God's existence is proved by a series of rational arguments--where objections are analyzed, authorities are consulted and weighed, multiple distinctions are made, and the whole emphasis is upon reason rather than observation. Saint Bonaventura seems to have as his purpose a demonstration of God's existence and of His traits which is not irrational but nonrational. That is, he would be far from saying that his conclusions would not stand up under rational criticism, but would insist that his method, to use modern language, is empirical rather than rational. To take a trivial example from another field, we could prove that a person had committed a crime either by circumstantial evidence or by direct testimony. If we can produce two or three persons who actually saw him commit the crime, we do not feel that we must corroborate what they say by a rational demonstration that he could have committed it, that he had a motive for committing it, that he threatened to commit it, that no one else could have committed it, and so on. We like to think that a good case gives us both kinds of evidence, but frequently we have to be satisfied with one type or bits of both types. Saint Bonaventura might be compared to the man who insists on direct testimony; Saint Thomas to him who puts his trust exclusively in circumstantial evidence, though the comparison would be superficial. It would be superficial since both would agree that God's existence could be shown in both ways.

The method of direct observation by which one is made certain of one's beliefs leads step by step to the mystic vision. The mystic, like the strict empiricist, has a kind of knowledge which is indisputable. No one can deny what the mystic sees any more than one can deny what the sensory observer sees. The philosopher who bases all knowledge upon the direct observation of colors, sounds, shapes, and so on, has knowledge which he readily admits is uncommunicable, in spite of the fact that most of us use words for our elementary sensations in the same ways. But whether John Doe, who is looking upon a patch of red, sees precisely what Richard Roe sees, could be doubted and has been doubted. For the psychological equipment, the sensory apparatus of the two men may and probably does contribute something to even the most simple sensory experiences. If Messrs. Doe and Roe are exactly alike in all relevant ways, then one may reasonably conclude that their sensations are exactly alike. But nevertheless Roe would not be having Doe's sensation, for each man is the terminus of causal events which diverge from a given point and which cease to be identical once they have entered the human body Thus a bell may be ringing and therefore giving off air waves. When these air waves enter the body of Roe, they are no longer the same waves which have entered the body of Doe for Roe's auditory nerves, no matter how similar to Doe's, are not existentially identical with them. If we distinguish between existential and qualitative identity, and we all do, then we may say that Doe and Roe have qualitatively identical but existentially nonidentical sensations. Until Roe can hear with Doe's ears and auditory nerves and auditory brain centers, he will never experience Doe's auditory sensations. Similarly with the mystic vision. If one man has such a vision, he is not made uneasy the fact that another does not have it. The other man has only to follow the discipline which will lead him to it. Saint Bonaventura traces the steps on this road, one by one, until he reaches his goal.

The mysticism of Saint Bonaventura was peculiar in that it was based on a theory of knowledge in which all degrees of knowledge were similarly direct, immediate, and nonrational. One sees God's traces in the sensory world; one sees His image in the mind; one sees His goodness in human goodness; one sees His powers in the operations of our own powers--it is always a question of direct seeing. Thus we have the possibility of real, rather than notional, assent in all fields of knowledge. We are not forced to know about things; we can know them. We have, to use other familiar terms, direct acquaintance with, rather than descriptions of, them. In other words, there is never any real need for rational discourse, for erudition. The simplest man of good will can see God as clearly as the most learned scholar. That made a philosophy such as this a perfect instrument for the Christian, for throughout the Christian tradition ran a current of anti-intellectualism. Christianity was held to be a religion, not merely a body of abstract knowledge. It was an experience as well as a theory. A man of faith could have as certain knowledge of God as the man of learning. This did not discourage the Christian from attempting to build up rational systems which would demonstrate to the world of scholars what the religious man knew by faith. Far from it. But what Kant was to say of the relationship between concepts and precepts, the Christian could have said of that between faith and reason, or religion and philosophy: faith without reason is blind, reason without faith empty.

The difficulty with the extremists who maintained that either one or the other faculty was sufficient was that faith and reason were both supposed to assert something. Whether you believed by faith or by reason, you believed in ideas which presumably made sense, could be stated in words, could be true or false. If you believed in one of these truths by faith, without reason, you were in the position of a man who had no knowledge of what he was believing nor why, nor even whether there was any good reason for believing in it rather than its contradictory. It was all very well for a man like Tertullian to maintain that there was more glory in believing something irrational--inept--than in believing something demonstrably true. Most Christian philosophers were anxious to put a sound rational underpinning beneath their beliefs. Similarly, if you had only rational knowledge, you were like a blind man who might be convinced that there were such things as colors, analogous to sounds and odors, but who had no direct acquaintance with them; or again like a man who had read an eloquent description of a great painting, but who had never seen it. Though all Christians were in the position of maintaining that there were some beliefs, those in the mysteries, which could not be rationally demonstrated, nevertheless they all, including Saint Bonaventura, pushed their rational demonstrations as far as they were able. Thus Saint Bonaventura goes so far as to attempt a dialectical proof of the dogma of the Trinity (Ch. VI), though he realizes that such a proof is not sufficient for religion.

It is worth pointing out that Franciscan philosophy as a whole tended to put more emphasis upon the observation of the natural world than its great rival, Thomism, did. Even in the "Little Flowers" of Saint Francis, only in a remote sense of the word a philosophical work, there is a fondness for what we call Nature which led him at times close to heresy. Later there were Franciscans like Roger Bacon, Duns Scotus, and their great friend and protector, Robert Grosseteste, whose interest in what we would call science, as distinct from philosophy, was almost their main interest. Indeed, one might without too much exaggeration maintain that the impetus to the study of the natural world through empirical methods came from the Franciscans. This appears in the early chapters of the "Itinerarium," where observational science becomes not simply the satisfaction of idle curiosity, but the fulfillment of a religious obligation. But it goes without saying that a man of science may discover truths which contradation of this conflict is found in the use made of arithmetic by allegorists, as early as Philo.ict what he has believed on faith and that a man of faith may look to science, not for everything which it is capable of revealing, but only for those things which corroborate his faith. The best illustr Few mathematicians today would play upon the curious properties of numbers--virgin numbers, perfect numbers, superabundant numbers, numbers which are the sums of such numbers as three and four--to prove religious truths. Few men of religion would, I imagine, seek validation of their religious beliefs in the properties of numbers, finding it extraordinary that there are four Gospels, four points of the compass, four winds, four elements (earth, water, air, and fire), four seasons, four humors, four temperaments. But all men will usually feel uneasy in the presence of contradiction and will do their best to bring all their beliefs into harmony with one another. The question reduces to the motivation of knowledge, the question of why exploration is pushed into fields which previously have been terrae incognitae. And when one compares science as it was before the fourteenth century and that which it became after that date, one sees that only a strong emotional propulsion would have produced the change of interest. That propulsion, we are suggesting, came from the Franciscans.

The student who has no acquaintance with the philosophy of Saint Bonaventura can do no better than to begin with the "Itinerarium." It is short and yet complete; it is typical of his manner of thinking; and it presents only the difficulties which any medieval philosophical text presents. There is no need to hack one's way through a jungle of authorities, quotations, refutations, distinctions, and textual exegeses. It is not a commentary on another man's book; it is a straightforward statement of a philosophical point of view. It illustrates the manner in which its author's contemporaries and predecessors utilized Biblical texts, and it also illustrates the knowledge of physics and psychology which was current in the thirteenth century. It is thus one of those representative documents which it behooves all students of intellectual history to know. It should be read with sympathy. One should accept its author's various assumptions, both methodological and doctrinal, and begin from there. There would be no point in trying to translate it in terms of the twentieth century, for the attempt would fail. But similarly one would not attempt to translate Dante's cosmology into modern terms nor justify Chartres Cathedral in terms of functional architecture as that is understood by modern engineers. This book is a kind of prose poem, with a dramatic development of its own as one rises from step to step toward a mystic vision of God. That would seem to be the best approach which the beginner could make to it.


1. The student will do well to read Philo's "Allegorical Interpretation" for examples of his method. The most readily available translation is that of G. H. Whitaker in the Loeb Library. For a thorough study of the whole matter, he should consult H. A. Wolfson s "Philo" (Cambridge: Harvard University, 1949).



July, 1953

St. Bonaventura, "Breviloquium," tr. by Erwin Esser Nemmers, St. Louis an London, 1946.

"Opera Omnia," As Claras Aquas (Quaracchi), 10 vols., 1937.

Dady, Sister Mary Rachael, "The Theory of Knowledge of St. Bonaventura," Washington, D. C., 1939.

De Benedictis, Matthew M., "The Social Thought of St. Bonaventura," Washington, D. C., 1946.

Gilson, E. H., "La Philosophie de St. Bonaventure," Paris, 1924.

Healy, Sister Emma Therese, "Saint Bonaventura's De reductione artium ad theologiam" (commentary with introduction and translation), St. Bonaventura, N. Y., 1939.

Prentice, Robert P., "The Psychology of Love according to St. Bonaventura," St. Bonaventura, N. Y., 1951.

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