1. Introduction

In the preface to his Commentary on the Book of Causes, St. Thomas Aquinas explains his understanding of the purpose of that work: "The aim ... of this book called On Causes is to delineate the first causes of things."⁽¹⁾ To him that project is no mere academic exercise, but something that touches the deepest longing of the human spirit. Aquinas believes that all of life is a search for happiness and that the "ultimate happiness possible in this life must lie in the consideration of first causes, because what little we can know about them is worthier of devotion and nobler than all that we can know about lower things."⁽²⁾

The same human hankering for first causes is at work in the efforts of contemporary theologians to describe divine action in ways compatible with our understanding of science. Those attempts are often frustrated, however, by the inadequacy of our notion of causality.

The aim of this paper is, in some way, to address that frustration by employing the rich resources of The Book of Causes and Aquinas' Commentary. We will first review some differences between classical and contemporary notions of causality and then consider certain dilemmas that arise when we try to use our idea of causality to speak of divine action. Next, we will consider the notion of causality in The Book of Causes and the ways that Aquinas modifies it in his Commentary. Finally, we will suggest how Aquinas' understanding of divine causality may be useful in addressing some of the contemporary issues in the discussion of divine action.

2. Causality and divine action

2.1. The classical notion of causality.

The classical notion of causality is succinctly expressed in Aquinas' Commentary on Aristotle's Physics: "Those upon which others depend for their being or becoming are called causes."⁽³⁾ The key characteristic here is ontological dependency.

The earliest Greek philosophers recognized that one thing may be materially dependent on another and searched for the fundamental material principle out of which the whole cosmos was composed. Later, Plato saw the changing world of human sense experience as somehow dependent upon unchanging forms or ideas. Changeable things participated in the unchanging reality of the subsistent forms or exemplar causes and depended on them for their intelligibility.

Aristotle retained the notion of formal cause, but viewed it as an intrinsic principle in substances rather than an extrinsic exemplar. Each changeable substance must be composed of two intrinsic principles, formal and material. The formal cause explains why a substance exists as this particular kind of thing, and the material cause explains why it can cease to be what it is and become something else. Aristotle also investigated the nature of efficient and final causality. The efficient cause is the agent or source of some change. It may be the actual doer of a certain act (the man who builds the house), but can also be the instigator of the action in a broader sense (not the actual builder, for instance, but the one who gives advice on how to build).⁽⁴⁾ The final cause is the purpose or aim of a certain action. It is that for the sake of which something is done, as a house might be built for the sake of shelter.

Aquinas adopts Aristotle's explanation of the four fundamental kinds of causes, but also finds a place for Plato's exemplar causes, not as subsistent forms but as ideas in the mind of God: "In the divine wisdom are the types of all things, which types we have called ideas--i.e., exemplar forms existing in the divine mind."⁽⁵⁾

In this classical understanding, causality is an analogous notion that can be employed in a number of ways. The material stuff of the universe can be seen as a cause, but so can ideas in the mind of God. The sculptor is the cause of a statue, but so is the form or shape of the statue itself. A cause is always that upon which something depends for its being or becoming, but the modes of causality and dependency vary greatly depending on the kinds of causes involved.

2.2. The contemporary idea of causality

This richly nuanced classical understanding of causality has been largely lost to contemporary thinkers. Cristina D'Ancona Costa prefaces her translation of Aquinas' Commentary on The Book of Causes, by noting how much the notion of causality has changed from his time to ours. Where the modern mind sees only a rather flat "necessary consequentiality" between events, the medieval intellect beheld a profound "metaphysical order."⁽⁶⁾

Mario Bunge points out the important role that empirical science has played in this shift in our understanding of causality:

The Aristotelian teaching of causes lasted in the official Western culture until the Renaissance. When modern science was born, formal and final causes were left aside as standing beyond the reach of experiment; and material causes were taken for granted in connection with all natural happenings... Hence, of the four Aristotelian causes only the efficient cause was regarded as worthy of scientific research.⁽⁷⁾

Since the method of empirical science relied on measurement and mathematics, only what was measurable could fall within its compass. Notions such as final and formal cause gradually dropped out of its considerations since they could not be represented mathematically.⁽⁸⁾

The understanding of efficient causality itself was also narrowed. No longer embracing either the builder or the one who gave advice on building, it was conceived exclusively in terms of the force or energy that moved the atoms of the universe.⁽⁹⁾ With David Hume, even this narrow idea of efficient causality was called into question. Since the supposed influence of a cause upon its effect was not directly evident to sense observation, Hume concluded that the connection between cause and effect was not an aspect of the real world, but only a habit of our thinking as we become accustomed to see one thing constantly conjoined to another. Causality became not a property of things but of thought. It was no longer an ontological reality in the world outside ourselves, but an epistemological property of the way we think about the world. The hallmark of causality was found in the epistemological category of predictability rather than the ontological category of dependence.

2.3. The problem of speaking of divine causality

As the way we understand causality narrows, so too does our ability to speak of divine causality. As Philip Clayton notes, "The present-day crisis in the notion of divine action has resulted as much as anything from a shift in the notion of causation."⁽¹⁰⁾ If causality can be thought of only as physical force, then divine causality must be explained in those terms. Frank Dilley accordingly insists that "defenders of miracles ought to be bringing forth real explanations, in terms of physics for example, of how it is that God acts."⁽¹¹⁾

But when God's action is conceived as one more physical force within the world, it seems to interfere with the determined patterns of scientific law. Albert Einstein sensed this when he argued that there was simply no "room" in the universe for divine causality:

The more man is imbued with the ordered regularity of all events the firmer becomes his conviction that there is no room left by the side of this ordered regularity for causes of a different nature. For him neither the rule of human nor the rule of divine will exists as an independent cause of natural events.⁽¹²⁾

Some contemporary theologians have been led to the same conclusion. Gordon Kaufman wonders how God can intervene in the world without "violently ripping into the fabric of history or arbitrarily upsetting the momentum of its powers."⁽¹³⁾ Langdon Gilkey explains this reluctance of contemporary theologians to speak of divine intervention:

Thus contemporary theology does not expect, nor does it speak of, wondrous divine events on the surface of natural and historical life. The causal nexus in space and time which Enlightenment science and philosophy introduced into the Western mind and which was assumed by liberalism is also assumed by modern theologians and scholars; since they participate in the modern world of science both intellectually and existentially, they can scarcely do anything else.⁽¹⁴⁾

Faced with these dilemmas, a number of theologians have tried to exploit certain developments within science itself to show how God might be thought of as acting in the world without interfering with it. John Polkinghorne, for instance, believes that chaos theory, can be understood in a way that leaves "room for divine manoeuvre."⁽¹⁵⁾ Robert Russell uses aspects of the indeterminacy of quantum physics to the same purpose: "[W]e can view God as acting in particular quantum events to produce, indirectly, a specific event at the macroscopic level, one which we call an event of special providence. ... [Q]uantum mechanics allows us to think of special divine action without God overriding or intervening in the structures of nature."⁽¹⁶⁾

A particular concern (and controversy) in these accounts involves the "causal joint," the particular point or way that divine causality can be conceived of as interfacing with the physical world. As Philip Clayton explains, "If one is to offer a full theory of divine agency; one must include some account of where the 'causal joint' is at which God's action directly impacts on the world. To do this requires one in turn to get one's hands dirty with the actual scientific data and theories, including the basic features of relativity theory, quantum mechanics and (more recently) chaos theory."⁽¹⁷⁾ The difficulties of naming such a "causal joint," however, are evident in the work of Arthur Peacocke who maintains that "the continuing action of God with the world-as-a-whole might best be envisaged...as analogous to an input of information rather than of energy." The problem with this notion, as Peacocke recognizes, is that in physics "any input of information requires some input of matter/energy." Such matter/energy input on God's part, however, smacks of interference with the order of the world. Peacocke concludes that he has located, but not solved, the problem of the "causal joint": "How can God exert his influence on, make an input of information into, the world-as-a-whole without an input of matter/energy? This seems to me to be the ultimate level of the 'causal joint' conundrum, for it involves the very nature of the divine being in relation to that of matter/energy and seems to be the right place in which to locate the problem..."⁽¹⁸⁾

Peacocke's dilemma points out the inherent limitations in these approaches to divine action. No matter how ingenious, all of them are hampered by a narrowly conceived understanding of the nature of causality. Even if quantum mechanics and chaos theory have overcome the determinism of the Newtonian universe, our ability to speak of God's action in the world will continue to be impaired as long as we think of causality only in terms of matter and energy.⁽¹⁹⁾

But why should we go on thinking of causality in such limited terms? There are some voices today who argue that, even within empirical science, a broader understanding of causality is required. William Wallace, O.P., has suggested that "nature" or "formal cause" is one type of causality that science needs to retrieve.⁽²⁰⁾ Michael Behe and William Dembski have made similar arguments for the notions of "purpose" and "design" in the science of biology.⁽²¹⁾ Others find evidence of design in the "fine tuning" of the earliest stages of the universe, where even small variations of certain key factors might have prevented the very formation of a universe capable of human life.⁽²²⁾

If broader understandings of causality are needed in science itself, how much more are they needed in those realms of thought which reach far beyond the limits of science, even to the first causes of all things? If we are to discover or rediscover such broader modes of causality, what better place to begin than The Book of Causes?

3. The Book of Causes

Compared to contemporary hedgings and qualifications about divine action, The Book of Causes is refreshingly bold and bracing in its pronouncements. It seeks nothing less than to explain the order and influence of the first causes of all things, and it intends to do this in thirty-two succinct propositions.⁽²³⁾

The original author of the book is unknown. Some contemporary scholars, including Henri Dominique Saffrey, O.P., believe it to have originated from Baghdad in the ninth or tenth centuries. Others think that it was written in Spain in the twelfth century. Of these, Adriaan Pattin, O.M.I., argues strongly that Albert the Great was correct in attributing the work to "David the Jew" (Ibn Daoud), the twelfth-century scholar of Toledo.⁽²⁴⁾

It is generally recognized that the work first became available to the Latin world through the translation of an Arabic text accomplished in Toledo by Gerard of Cremona in the twelfth century.⁽²⁵⁾ The book was initially thought to be a work of Aristotle, a distinction that aroused both interest and suspicion. First used by Alan of Lille, it soon became the common property of many medieval scholars. Though initially banned at Paris with certain other works of Aristotle, it was later accepted and then, in 1255, became a required text for the Faculty of Arts at the University under the title, "The Book of Aristotle on the Exposition of Pure Goodness.⁽²⁶⁾

Rooted in the Neoplatonic tradition, The Book of Causes employs the Enneads of Plotinus and is enormously dependent (as Aquinas would discover) on Proclus, often quoting directly from his Elements of Theology. From both it inherits the Neoplatonic vision of the universe as a hierarchy of beings beginning with God, the First Cause, and descending through intelligences and souls to material reality. The world is a nexus of causes in various grades of being and perfection in which the higher causes influence the lower.

In its description of causality, The Book of Causes demonstrates that its author was not only a borrower but also an innovator within the Neoplatonic tradition who diverged from the teaching of Proclus at certain key points.

Proclus (410-485) was among the last "Platonic successors" or administrators (diadochi) of the Athenian School before it was closed for its pagan teachings by the Christian emperor Justinian in 529.⁽²⁷⁾ A pagan himself, Proclus was hostile to Christianity and populated his philosophical universe with a hierarchical pantheon by identifying his hypostases of supreme perfections (the henads) with the traditional Greek gods.⁽²⁸⁾ (This was at best a rather odd philosophical fate for the Greek deities, as E.R. Dodds remarks: "that Homer's Olympians, the most vividly conceived anthropomorphic beings in all literature, should have ended their career on the dusty shelves of this museum of metaphysical abstractions is one of time's strangest ironies.")⁽²⁹⁾

Proclus' universe is instantiated through a series of emanations, as the One produces Intelligence, which in turn produces Soul which gives rise to Nature or the sensible world. The causality at work in these emanations is spontaneous and necessary.⁽³⁰⁾ In this procession, each higher realm is immanent in the effect which proceeds from it, and, by a kind of return, each lower realm is present by participation in the higher or exemplar from with it originates.⁽³¹⁾

The Book of Causes differs most significantly from Proclus by espousing not just a series of emanations or over-flowings of one cause into the next, but a true doctrine of creation which the author seems to have derived from the divine revelation of the Hebrew, Christian or Islamic tradition.⁽³²⁾ The First Cause produces not just the next rank of beings, but is the source of the being and the causality of all things: "The First Cause is neither Intelligence nor Soul nor Nature; on the contrary, it is above Intelligence and Soul and Nature, because it creates all things."⁽³³⁾ For this reason, it is also present to all things. Other causes act under its influence, not to give being but only to give form. The Soul, for example, may cause a thing to live (to have the form of life), but it does not cause the thing to be.⁽³⁴⁾

The Book of Causes also differs from Proclus by viewing the subsistent perfections of the henads not as Greek gods but as as properties of the One God, the First Cause. This change also seems to be derived from a revealed monotheism, though the author does not explicitly affirm that the First Cause is free or personal.⁽³⁵⁾

4. Aquinas and The Book of Causes

Aquinas was already familiar with The Book of Causes when he wrote his earliest works. In the Scriptum super Libros Sententiarum and the De ente et essentia (1252-1256), he frequently attributes the book and its teaching to "the philosopher," a designation he generally reserves for Aristotle.⁽³⁶⁾ There are signs in the De ente et essentia, however, that Aquinas is beginning to question whether the book should be attributed to Aristotle.⁽³⁷⁾ In his In Librum Boethii de Trinitate Expositio (1258-59) and in his Quaestiones Disputatae de Veritate (1256-59), he refers to the author as "the philosopher," but it is disputed whether in these contexts the term truly refers to Aristotle or to an unknown author.⁽³⁸⁾ Toward the end of his career, Thomas read Proclus' Elements of Theology in a new translation by William of Moerbeke and became the first to recognize that work as the true source of The Book of Causes.⁽³⁹⁾ He announced his discovery in the preface to his Commentary.⁽⁴⁰⁾

Thus we find a collection of writings on first principles that are divided into different propositions, in a way similar to the procedure of those examining certain truths one at a time. and in Greek we find handed down a book of this type by the Platonist Proclus, which contains 211 propositions and is entitled The Elements of Theology. And in Arabic we find the present book which is called On Causes among Latin readers, [a work] known to have been translated from Arabic and not [known] to be extant at all in Greek. Thus, it seems that one of the Arab philosophers excerpted it from this book by Proclus, especially since everything in it is contained much more fully and more diffusely in that of Proclus.⁽⁴¹⁾

In his Commentary, Aquinas set himself the task of comparing The Book of Causes to Proclus' Elements, showing the similarities and differences between the two works and correcting their teaching where necessary using the philosophy of Aristotle and the theology of Dionysius.⁽⁴²⁾ We will review Aquinas' Commentary as it deals with the notion of divine causality, showing where he modified the teaching of that work and where he accepted it and incorporated it into his own theology.⁽⁴³⁾ In this, we will make use of Aquinas' other writings as well.

4.1. The nature of divine causality

4.1.1. The primacy of efficient causality

Aquinas understands the whole teaching of The Book of Causes to follow from its first proposition: "Every primary cause infuses its effect more powerfully than does a universal second cause."⁽⁴⁴⁾ He analyzes this proposition into three points: "(1) that the first cause infuses the effect more powerfully than does the second cause; (2) that the impression of the first cause recedes later from the effect; (3) that it reaches the effect first." He then shows how the three points can be found in two propositions (56 and 57) of Proclus' Elements of Theology.⁽⁴⁵⁾

The Book of Causes illustrates the proposition with an example of formal causality. A more universal form such as "being" has priority over a less universal form such as "living" or "human." The prior and more powerful effect of "being" as a primary cause is seen in the fact that, even when something ceases to be a man or a living thing, that which remains is still being.

Aquinas accepts the example but goes on to find ways to illustrate the same principle in the cases of Aristotle's other three types of causes: material, efficient and final. In the order of material causality, prime matter has priority over secondary matter (substances) since substances in some way depend on it and since it endures through the changes to which they are subject. Likewise the first efficient cause has priority over secondary efficient causes since its power extends to more things and so "its proper effect must be more common." In particular, its power extends to the causality of the secondary efficient cause: "For the first cause itself produces and moves the cause acting secondarily and so becomes the cause of its acting." Similarly, the ultimate end or final cause has priority over more proximate ends since it is the reason why they are sought and since the desire for such ends "comes after the desire for the ultimate end and ceases before it."⁽⁴⁶⁾

Though the proposition applies to all four causes, Aquinas argues that it applies fundamentally to efficient causes and to the others "by derivation."⁽⁴⁷⁾ The primacy of the efficient cause over the material cause is explained by the fact that the "first and supreme cause" must be the very cause of matter: "[I]t is necessary that what first underlies all things be from the first cause of all things."⁽⁴⁸⁾

Aquinas maintains that "this principle applies to formal causes by derivation," but does not explicitly present his reasons for this asserrtion in his Commentary. The grounds for affirming the primacy of the efficient cause over the formal cause are explained, however, in his discussion of goodness in the Summa Theologica. There he makes a distinction between the order of causes in the act of causing and in the thing caused. In the thing caused, the form has primacy, for there is "first, the form whereby it is a being; secondly, ...its effective power, whereby it is perfect in being, for a thing is perfect when it can reproduce its like...; thirdly, there follows the formality of goodness which is the basic principle of its perfection." But in the act of causing, the order is the opposite: "in causing, goodness and the end come first, both of which move the agent to act; secondly, the action of the agent moving to the form; thirdly, comes the form."⁽⁴⁹⁾ So, it is clear that, in the act of causing, the efficient cause comes before the formal cause. But it is precisely the act of causing that is the concern of the first proposition.

If this argument establishes the priority of the efficient cause over the formal cause in the act of causing, it also seems to assert the priority of the final cause over the efficient cause in that same context. But in the Commentary on the Book of Causes, Aquinas maintains that even in that context efficient causality has priority over final causality, not because the efficient cause acts before the final cause, but because the final cause itself has the character of efficient causality: "[T]he end is a cause inasmuch as the end moves the efficient cause to act; thus, insofar as [the end] has the character of a mover, it belongs in a certain sense to the genus of efficient cause."⁽⁵⁰⁾ Here, Aquinas is not turning the final cause into an efficient cause. He is rather recognizing what makes the final cause to be a final cause. The end moves the agent insofar as the end is good or desirable. But since goodness or desirability implies activity or operation, the goodness of the final cause implies its operation, its "effective power, by which it is perfect in being,"⁽⁵¹⁾ As Lawrence Dewan explains, "the efficient cause is the place to look for finality."⁽⁵²⁾

Aquinas applies these various kinds of causality to God, affirming that God is the "first exemplary, effective, and final principle" of all things.⁽⁵³⁾ But the primacy of efficient causality remains. God's exemplar causality, for example, implies his efficient causality, since the exemplar is ordered toward the "production" of something.⁽⁵⁴⁾ God is the "first exemplar cause of all things" since there exists "in the divine mind a form to the likeness of which the world was made," and this form or idea in God "is identical with his essence."⁽⁵⁵⁾ But the reason for the similitude or likeness between God and creatures, as Thomas explains in the Summa contra gentiles, is that God is the first efficient cause:

All created things are, in a sense, images of the first agent, that is, of God, for the agent makes a product to his own likeness [agens enim agit sibi simile]. Now, the function of a perfect image is to represent its prototype by likeness to it; this is why an image is made. Therefore, all things exist in order to attain to the divine likeness, as to their ultimate end.⁽⁵⁶⁾

As God's exemplar causality is explained in terms of his efficient causality, so too is his final causality. So when Aquinas raises the question in the Summa Theologica of whether God is good, the reason he gives for divine goodness is not that God is the final cause (though this is certainly true), but rather that God is the efficient cause. For the goodness of the final cause (as we have seen) presupposes efficient causality:

To be good belongs pre-eminently to God. For a thing is good according to its desirableness. Now everything seeks after its own perfection; and the perfection and form of an effect consist in a certain likeness to the agent, since every agent makes its like; and hence the agent itself is desirable and has the nature of good. For the very thing which is desirable in it is the participation of its likeness. Therefore, since God is the first effective cause of all things, it is manifest that the aspect of good and of desirableness belong to him.⁽⁵⁷⁾

As Lawrence Dewan summarizes, "[I]t is quite clear that the goodness of God, i.e., his being an end, is being seen precisely in function of his being the agent whence all perfections flow."⁽⁵⁸⁾

Aquinas' arguments for the primacy of efficient causality point out a basic premise or intuition of his entire theology which distinguishes it from both the Platonic and Aristotelian philosophical traditions.⁽⁵⁹⁾ Plato gave priority to formal causality. Subsistent forms were the ultimate reality. Aristotle gave a certain priority to final causality. His "unmoved mover," the source of all activity in the cosmos, exercised its causality as a final cause, as an object of desire. For Aquinas, God is subsistent being itself, who alone communicates existence to creatures. And in this, God acts fundamentally as an efficient cause. Etienne Gilson explains the significance of this distinction:

[The immovable mover of Aristotle] moves only by the love it excites--which it excites, observe, but does not breathe in. When we read in the commentaries on the Divina Commedia that the last verse of the great poem merely echoes a thought of Aristotle's, we are very wide of the mark: l'amor che muove il Sole e l'altre stelle has nothing but the name in common with the first unmoved mover. The God of St. Thomas and Dante is a God who loves, the god of Aristotle is a god who does not refuse to be loved. The love that moves the heavens and the stars in Aristotle is the love of the heavens and the stars for god, but the love that moves them in St. Thomas and Dante is the love of God for the world; between these two motive causes there is all the difference between an efficient cause on the one hand and a final cause on the other.⁽⁶⁰⁾

4.1.2. The mode of divine causality

Aquinas tells us that God acts "by way of creating and infusing."⁽⁶¹⁾ Only God acts in these ways since, unlike any creature, he is both complete or self-subsistent and unlimited in the actuality of his existence: "[S]ince the form, which is the principle of action, is, in [what is complete among us], limited and participated, it cannot act by way of creation or infusion, as does what is totally form, which in itself is totally productive of other things by a participation [participatione] in itself."⁽⁶²⁾ In this way, God "creates things and infuses them with goodnesses with a complete infusion....because he is subsistent goodness without limit..."⁽⁶³⁾

For Aquinas the "act" of creation is not a kind of medium between God and creatures by which God brings creatures into existence. With respect to God, the act of creation is God himself: "Creation signified actively means the divine action, which is God's essence."⁽⁶⁴⁾ With respect to the creature, creation does not signify the passive reception of something since, in the event of creation (unlike the event of motion or change where, for example, a piece of clay can acquire a new shape), there is no passive potentiality already somehow "there" to receive the new actuality. Creation in the creature rather implies only "a certain relation to the Creator as to the principle of its being."⁽⁶⁵⁾ This is, of course, a real and indispensable relationship for the creature since, without it, it would cease to exist. On God's part, however, there is no added or intervening relationship. God is immediately and most intimately present to the creature as the source of its being.⁽⁶⁶⁾ Any relationship somehow "added on" to God's existence would only diminish God's immanence in the creature since it would make God a being of the same order as the created thing and so unable to be the source of its being and so most intimately present to it.⁽⁶⁷⁾

Likewise, when we think of God as somehow "infusing" the already existing creature with additional qualities or goodness, this act on God's part can be nothing other than God's essence which is his existence. On the part of the creature, however, this act may be characterized as a "participation" in God arising from God's efficient causality:

[I]f the proper activity of any thing is found in another thing, then that thing must of necessity possess this activity from a participation of the other thing [ex participatione alterius] as an effect possesses something from [its] cause.⁽⁶⁸⁾

In particular, God's action in creatures can be seen as a participation in God's power:

[O]f the perfections coming to things from the first cause, there is something that reaches all things, even down to generable and corruptible things, namely, being. But there is something that does not reach effects insofar as they are effects but only causes insofar as they are causes, namely power. Hence the participation of power [participatio virtutis] reaches as far as nature, which has the character of a principle.⁽⁶⁹⁾

And the creature's action, in turn, can be seen as a product of this participation:

Now, whatever abundantly participates a characteristic proper to some thing becomes like it not only in form but also in action. ... Because form is the principle of action, everything that acquires its action from an abundant participation of the infusion of a higher agent [ex abundanti participatione influxus superioris agentis] must have two actions: one according to its proper form, another according to a form participated from the higher agent, as a heated knife cuts according to its proper form but burns insofar as it is heated.⁽⁷⁰⁾

4.2. Divine causality and the causality of creatures

4.2.1. The influence of the first cause on secondary causes

The relative roles of the first cause and the second cause in producing an effect are analyzed in some detail in the first proposition of The Book of Causes. Aquinas agrees with its basic teaching that the "remote cause is more powerfully the cause of a thing than the proximate cause that follows it." The Book of Causes explains that "the first cause aids the second cause in its activity, because the first cause also effects every activity that the second cause effects, although it effects it in another way [which is] higher and more sublime."⁽⁷¹⁾

Aquinas describes more explicitly the relation of the first cause to the activity of the second cause: "[T]he activity by which the second cause causes an effect is caused by the first cause, 'for the first cause aids the second cause,' making it to act. Therefore, the first cause is more a cause than the second cause of that activity in virtue of which an effect is produced by the second cause."⁽⁷²⁾ Aquinas notes that Proclus proves this principle "more explicitly" than The Book of Causes. Proclus points out that, because a second cause has its own substance from the first cause, it likewise has its power to act from the first cause. Since that power produces the effect, the fact that "the second cause is the cause of its effect is due to the first cause" and the first cause is therefore "more the cause of the effect than the second cause."⁽⁷³⁾ Here, it is clear that the effect is produced by both the first and the second cause, but it is due primarily to the first cause which is the source of the substance and activity of the second.

4.2.2. The influence of the first cause and secondary causes in the creation and governance of the universe

The universe of The Book of Causes, as we have noted,⁽⁷⁴⁾ is a Neoplatonic world with four levels of being: the first cause, intelligences, souls, and material things. In Proposition 2, the different levels are defined in terms of their relationship to eternity. The relative causal influences of these different realms can be seen in Proposition 3, where the activity of a divine soul, the animator of a heavenly body, is related to that of the intelligences and the first cause.

The first activity of divine soul is to provide for nature. This activity is called "divine" since it participates the power of the first cause. Aquinas explains that the divine soul provides for nature "inasmuch as it is the principle of the first motion to which all nature is subject." It exercises this activity "through the power that it participates from the first cause, which is the universal cause of all things, from which it gains a certain universal causality over natural things." God's power is exemplified in this soul in that "just as God is the universal cause of all beings, so that soul is the universal cause of natural things that are in motion."⁽⁷⁵⁾

The second activity of the divine soul is to know things. This activity is called "intellectual," and participates "the power of an intelligence."⁽⁷⁶⁾

The third activity of the divine soul is called "animate." By it, the soul moves the first body and so acts as the cause of motion in things. This seems to be the proper activity of a divine soul, but it is also a reflection, on a lower plane, of the activity of an intelligence. For an intelligence impresses the soul with knowledge in a way that is without motion, but the soul can impress the material realities below it only through motion. The influence of that higher cause or intelligence is evident in the kind of motion that the soul produces since "all natural bodies directly arrive at their fitting ends through their activities and motions, which could not happen unless they were directed by something intelligent."⁽⁷⁷⁾

The Book of Causes explains that the divine soul can carry out activities that belong properly to higher powers "only because it is an image of a higher power." And it is an image of those powers "because the first cause created the being of soul with the mediation of an intelligence."⁽⁷⁸⁾

Aquinas discusses these causal influences in terms of the relationship between participation and efficient causality. "Every effect participates something of the power of its cause. So it remains that the soul, just as it performs a divine activity insofar as it is from the first cause, so too it performs the activity of an intelligence insofar as it is from [an intelligence] and participating its power." Since the soul participates both in the activity proper to God and the activity proper to an intelligence, it must somehow come from both as its efficient cause: "[T]he soul is from God as first cause, but from an intelligence as second cause."⁽⁷⁹⁾

Aquinas notes that some have interpreted this last phase as implying that an intelligence acts as an instrumental cause in the creation of the soul.⁽⁸⁰⁾ He argues that this interpretation would be contrary to the teaching of the Platonists themselves that the subsistent form of being is the cause of being in all things, just as the subsistent form of life is the cause of living and the subsistent form of intelligence is the cause of understanding. In this Platonic view of the world, it would not make sense for the being of the soul to be created through the instrumentality of an intelligence. Rather, the being of the soul must be from the first cause, while its intellectual character may be due to an intelligence. It is in this way that the first cause is said to create the being of the soul "with the mediation of an intelligence."⁽⁸¹⁾

Having carefully explained this Platonic view of things, Aquinas then rejects it as "repugnant to the truth as well as to the opinion of Aristotle." For if the soul had its being from one cause and its intellectual nature from another, the soul would not be absolutely one. Aquinas therefore argues "that the soul not only has essence but also [has] intellectuality from the first cause."⁽⁸²⁾

Aquinas' disagreement with the teaching of The Book of Causes on this point brings out the difference between their respective understandings of the term "being."⁽⁸³⁾ For Aquinas, being (esse) is the act of existing, the "to be" which explains the fact that a thing is. It is distinguished from essence, which explains what a thing is, and which stands in relationship to esse as potentiality to act. God is subsistent "to be" itself (ipsum esse subsistens) and as such is the immediate source of existence in all things.⁽⁸⁴⁾

For the author of The Book of Causes, however, "being" is not understood as an existential act, but as "the formal substrate upon which life and intelligence are received."⁽⁸⁵⁾ The First Cause is the source of this universal formal substrate of all things, but other causes (the intelligences) then determine the particular type or species of each. Aquinas explains this position:

The Platonists asserted that what is common in anything is caused by one principle, while what is more proper is caused by another principle that is lower. So, according to this, a soul abiding steadfastly in itself has its being from the first cause. But that it is intellectual and that it is a soul result from second causes, which are intelligences.⁽⁸⁶⁾

Aquinas, however, insists that the entire nature of the creature is from God: "We must say that it is from the first cause, from which such a soul has its being that it is also intellectual and that it is a soul and consequently that it is impressed upon the body. Accordingly the soul does not result from the impression of an intelligence but from the impression of the first cause."⁽⁸⁷⁾ The first cause itself can be the ultimate source of intelligence and life as well as of being since it (and not some other hypostasis or subsistent form) is wisdom, life and being itself: "Therefore, one has to say that the soul not only has essence but also [has] intellectuality from the first cause. This accords with the opinion of Dionysius... that good itself, being itself, life itself and wisdom itself are not different but one and the same thing, which is God, from whom things derive that they are, that they live and that they understand."⁽⁸⁸⁾

Though Aquinas denies that secondary causality can be involved in the act of creation, he does agree with The Book of Causes on the role of secondary causality in the governance of the universe. Both Aquinas and The Book of Causes see secondary causality at work in the way that motion is originally initiated in material things. The Book of Causes ascribes this to the soul of a heavenly body and Aquinas, to "the mediation of intelligences or angels."⁽⁸⁹⁾ The secondary causality of intelligences and heavenly bodies is also involved in human generation and in the conservation of things in being.⁽⁹⁰⁾

4.3. Divine transcendence

The confident program of The Book of Causes to explain the order and influence of the first causes of all things is tempered by a frank admission of the utter transcendence of the first cause and the consequent limits of our knowledge of it: "The first cause transcends description. Languages fail in describing it only because of the description of its being. For [the first cause] is above every cause and is described only through the second causes which are illumined by the light of the first cause."⁽⁹¹⁾

Aquinas agrees entirely with this estimate of the limits of our knowledge of God: "The most important thing we can know about the first cause is that it surpasses all our knowledge and power of expression. For that one knows God most perfectly who holds that whatever one can think or say about Him is less than what God is."⁽⁹²⁾

Systematizing the arguments from The Book of Causes, Thomas points out that a thing can be known in three ways: "in one way as an effect through a cause, in another way through itself, and in a third way through an effect." The first cause cannot be known though a cause since there is no cause above it. Nor is it known through itself since things are known through themselves by sense, imagination, intellect or reasoning. The first cause, however, is above all things which fall under any of these ways of knowing. Finally the first cause cannot be known through an effect since "a cause which surpasses its effect cannot be sufficiently known through its effect." God cannot be known as such through his effects, but he can be signified through them. When we speak of or signify God in this way, however, we must remember that he entirely surpasses our mode of signifying him.⁽⁹³⁾

In the course of these arguments, Aquinas explains how he differs from Proclus in saying that the first cause is "above being" and hence unknowable. Proclus believes that the first cause, as the essence of goodness and unity, surpasses "separated being itself," which he considers a secondary cause, even though it is the "first and supreme of all that participate what is properly divine."⁽⁹⁴⁾ Thomas explains his reason for saying that God is above being by introducing the distinction between esse (the act of existing) and ens (a being composed of esse and essence):

[T]he first cause is above being inasmuch as it is itself infinite "to be." "Being," however, is called that which finitely participates "to be," and it is this which is proportioned to our intellect, whose object is some "that which is"... Hence our intellect can grasp only that which has a quiddity participating "to be." But the quiddity of God is "to be" itself. Thus it is above intellect.⁽⁹⁵⁾

4.4. Divine immanence

Neither for Aquinas nor for the author of The Book of Causes does God's transcendence over creation imply any sort of distance of God from creatures. There is no contradiction between God's immanent involvement in the world through his "universal rule of things" and his transcendent unity "by which God is exalted above things."⁽⁹⁶⁾ God's influence "extends to all things," and God is most intimately present in each thing since "the cause is in the effect and conversely, insofar as the cause acts on the effect and the effect receives the action of the cause."⁽⁹⁷⁾

God acts though secondary causes, but his action is always in some sense immediate in that he does not act through any disposition or relationship added to his nature for "the first cause acts through its being" without any "disposition through which an agent is adapted or rendered proportionate to a patient, or a recipient."⁽⁹⁸⁾ On this point, Aquinas agrees with the teaching of Proclus, which he quotes:

The ones who provide (namely, the gods) do not receive a relation to those things for which provision is made, for through the being that they are they make all things good. Furthermore, what acts upon all things through being acts without relation, for relation is an addition to being, due to which it is outside [its] nature.⁽⁹⁹⁾

God does not need, after the manner of a finite agent, to act through "different dispositions by which it is adapted to diverse things," acting "in different ways upon different things according to different dispositions which are outside its nature or essence."⁽¹⁰⁰⁾ No relation or "connecting link" stands between God and his action in creatures:

But the first cause acts through its being... Hence it does not act through any additional relation or disposition through which it would be adapted to and mixed with things. And such a "relation" is called here a "connecting link" or mediating thing [continuator vel res media] because through such a disposition or relation an agent is adapted to a recipient, and is in a certain sense a mediating thing between the essence of the agent and the patient itself.⁽¹⁰¹⁾

Though God's activity is universally present in all things, it is not merely generic. Aquinas believes, on the contrary, that God can cause particular events in time even apart from secondary causes. He therefore disagrees with an argument, implied in The Book of Causes, that a sempiternal being cannot immediately produce temporal effects, but only sempiternal effects. He contends that, were such an argument true, "many of the foundations of the Catholic faith would be removed, for it would then follow that angels would be able to do nothing new in lower things immediately, and much less God, who is not only eternal but before eternity."⁽¹⁰²⁾ Rather, it must be affirmed that God can act in time even though he is eternal:

In this way God, too, can produce something in time that is new and did not exist previously, according to a defined proportion of this effect to this time, as happens in all miraculous effects produced immediately by God. Nor is this opposed to saying that God produces through his being, because his being is his understanding.⁽¹⁰³⁾

5. Implications for the contemporary discussion of divine action

We will conclude this paper with some brief suggestions on how the understanding of causality which we have discovered through Aquinas' Commentary on the Book of Causes might be useful in the contemporary discussion of divine action.

5.1 Divine transcendence

Perhaps the most fundamental thing we should take from Aquinas' discussion of The Book of Causes is the teaching on divine transcendence. The author of The Book of Causes, coming out of the Neoplatonic tradition in which the ineffable One is beyond word or thought, affirms that "the first cause transcends description."⁽¹⁰⁴⁾ Aquinas modifies this teaching according to his own metaphysics of esse, explaining that the first cause, as "infinite 'to be,'" is beyond our intellect, whose object is the participated being of creatures.⁽¹⁰⁵⁾

God's being utterly transcends our understanding. Yet something of God can still be "known through the effect."⁽¹⁰⁶⁾ Since the effect of an agent is in some way like the agent, something of the Creator can be known through the creature. We can therefore speak of God and his action using the analogy of creatures. At the same time, we must avoid speaking of divine action as if it were univocal with the action of creatures, since whatever we say of God "does not belong to him according to the way in which we signify it."⁽¹⁰⁷⁾

5.2. Divine causality and the causality of creatures

5.2.1. The types of causality

If our discussion of divine action is presently hampered by a too narrowly conceived understanding of causality, we might retrieve Aquinas' teaching on God as the efficient, exemplar and final cause of all things. Signs of the influence of God's final and efficient causality might then be found in the purposeful activity of creatures which, in seeking the perfection of their own natures, point to the Good in whom they have their source and whose perfection their own, therefore, somehow resembles. Indications of the influence of God's exemplar causality might be seen in the evidence of design which biologists are finding in the evolution of life and physicists are discovering in the "fine tuning" of the early stages of the universe.

5.2.2. Primary and secondary causality

A fundamental concern in the contemporary discussion of divine action is that God's activity in the world might somehow "interfere" with the ordered processes of nature described by the laws of science. Perhaps the notion of primary and secondary causality, as presented in The Book of Causes and developed in the thought of Aquinas, might allay some of those concerns. According to this teaching, the first cause does not interfere with the causality of a secondary cause, but is rather the very source of that causality: "[T]he first cause itself produces or moves the cause acting secondarily and so becomes the cause of its acting."⁽¹⁰⁸⁾ It is possible for the first cause to act in this way only because it transcends the whole order of the causality of creatures. When the transcendence of the first cause is overlooked, its influence on secondary causes becomes either an enigma or a contradiction.⁽¹⁰⁹⁾ When God's transcendence is affirmed, however, the divine influence can be seen as the ultimate source of the activity of all secondary causes, whether these necessary, contingent or free.

[T]he divine will must be understood as existing outside of the order of beings, as a cause producing the whole of being and all its differences. Now the possible and the necessary are differences of being, and therefore necessity and contingency in things and the distinction of each according to the nature of their proximate causes originate from the divine will itself, for He disposes necessary causes for the effect that He wills to be necessary, and He ordains causes acting contingently (i.e., able to fail) for the effects that He wills to be contingent. And according to the condition of these causes, effects are called either necessary or contingent, although all depend on the divine will as on a first cause, which transcends the order of necessity and contingency.⁽¹¹⁰⁾

Brian Shanely, O.P., explains how this teaching of Aquinas surpasses that of The Book of Causes:

[A]lthough Aquinas's original philosophical inspiration regarding the ubiquity and primacy of divine causation is rooted in the Neoplatonic doctrines of the Liber de Causis, his own metaphysical understanding of esse enabled him to give a deeper and more penetrating account of the totality and intimacy of divine causation than had hitherto been possible. When conceived primarily in terms of the creative causation of esse, the divine motion is not an exterior manipulation of created agents determining them to act one way or another. For just as creation is not a change, so too the divine motion is not the effecting of a change in something with independent existence; divine efficient causation is only a motion in an analogous sense. The primary mode of divine causation is creative and constitutive, not controlling and compelling. God is not rival or auxiliary to created causes, but rather the One who makes all causes be causes.⁽¹¹¹⁾

A proper appreciation of God's transcendence also allows us to affirm the possibility of God's acting directly in the natural world, even aside from secondary causes. If God is a transcendent agent "whose substance is not in time, but whose activity is in time," then he "can produce something in time that is new and did not exist previously, according to a defined proportion of this effect to this time, as happens in all miraculous effects produced immediately by God."⁽¹¹²⁾ Aquinas' teaching on this subject in the Summa Theologica seems to reflect the hierarchy of causality from The Book of Causes:

From each cause there results a certain order to its effects, since every cause is a principle; and so, according to the multiplicity of causes, there results a multiplicity of orders, subjected one to the other, as cause is subjected to cause. Wherefore a higher cause is not subjected to a cause of a lower order; but conversely. If therefore we consider the order of things depending on the first cause, God cannot do anything against [contra] this order; for, if he did so, he would act against his foreknowledge, or his will, or his goodness. But if we consider the order of things depending on any secondary cause, thus God can do something outside [praeter] such order; for he is not subject to the order of secondary causes; but, on the contrary, this order is subject to him, as proceeding from him... Wherefore, God can do something outside [praeter] this order created by him, when he chooses, for instance by producing the effects of secondary causes without them, or by producing certain effects to which secondary causes do not extend.⁽¹¹³⁾

The distinction between the first cause and secondary causes raises a concern in the contemporary discussion of divine action regarding the character of the "causal joint" where these two orders of causality meet. Here again, the teaching of Aquinas and The Book of Causes on the transcendence and immanence of the first cause can be helpful. Because of God's transcendence, he acts universally in all secondary causes. But, as the source of being, which is "innermost" in each thing, he also acts in each thing most intimately. Since God's action is one with his being and essence, there is, on his part, no intervening "joint" or "relation" between him and the creature in which he acts. To posit or require such a "joint" or relation would be to reduce God to the level of other causes which do act only "through such a disposition or relation"⁽¹¹⁴⁾ and so cannot be as intimately present to one another as God is to each of them.

5.3. A language for divine action

If the modern mind, under the influence of empirical science, tends to think of the word "cause" in terms of efficient causality only and to characterize that causality as a kind of force or impetus, it might be helpful to find an alternate terminology for our discussion of divine action.

A possible candidate is the notion of "participation" which Aquinas inherited from Neoplatonic philosophy but transformed according to his own metaphysics of esse. As Rudi Te Velde explains, "Aquinas's own approach in the question of how God operates in the operation of nature ... can be characterized by the participation formula 'transcendence in the immanence.'"⁽¹¹⁵⁾ Sr. Louise-Marie Antoniotti, O.P. suggests this terminology when she poses the question, "In what does this activating impression of God in the heart of the creature consist?", and answers by saying, "It is a participation of the universal, efficient power of God in lower causes."⁽¹¹⁶⁾ Aquinas himself describes divine action in the creature is simply as a "participation of power [participatio virtutis]."⁽¹¹⁷⁾

We have already seen, of course, that for Aquinas the whole notion of participation implies and presupposes efficient causality. But there may be certain advantages to using the language of participation rather than the language of efficient causality when we speak of divine action. If the term "causation" tends to arouse images of interference, the word "participation" seems to imply cooperation rather than intrusiveness. And if "causation" raises the imagined need for a "causal joint" in which cause and effect can somehow interface, "participation" raises no such specter since it accents the true intimacy which characterizes the action of God in the creature. As Antoniotti explains, "This expansion of the divine power, more precisely this participation of the power of God by the created agent, is completely interior to the acting creature."⁽¹¹⁸⁾

6. Conclusion

In this paper, we have tried to show how the understanding of divine causality in The Book of Causes and Thomas Aquinas' Commentary might be used to address certain dilemmas in the contemporary discussion of divine action. The key notion to be taken from those sources is that of divine transcendence. Only if we remember God's utter transcendence of created reality can we appreciate the absolute immediacy of his presence in all things and so find a way to speak of how all creatures participate his being, which is one with his action. In this, our langauge will still remain halting, even as our knowledge remains obscure. We are after all, as Aquinas reminds us, mere owls blinking in the sunlight.⁽¹¹⁹⁾. Yet however limited our understanding and however hesitant our speech, we may still say something about a truth that touches the deepest concerns of the human mind and heart, for, as Aquinas also teaches us, "the ultimate human happiness possible in this life must lie in the consideration of first causes, because what little we can know about them is worthier of devotion and nobler than all that we can know about lower things."⁽¹²⁰⁾

Bibliography

Alston, William P., "Divine Action: Shadow or Substance?," in The God who Acts: Philosophical and Theological Explorations, University Park, PA: Pennsylvania State University Press, 1994. p.41-62.

Antoniotti, Louise-Marie, O.P., "La premotion divine: saint Thomas d'Aquin et l'auteur du Liber de Causis," in Atti dell'VIII Congresso Tomistico Internazionale. Studi Tomistici 17, Citta del Vaticano: Libreria Editrice Vaticana, 1982. p.60-70.

Aristotle, Physics, in Richard McKeon, ed., The Basic Works of Aristotle, New York: Random House, 1941.

Bardenhewer, Otto, ed, Die pseudo-aristotelische Schrift Ueber das reine Gute bekannt unter dem Namen Liber de causis, Freiburg im Breisgau: Herder, 1882.

Bartholomew, D.J., God of Chance, London: SCM Press, 1984.

Behe, Michael J., Darwin's Black Box: the Biochemical Challenge to Evolution, New York: Free Press, 1996.

Behe, Michael J, "Darwin's Breakdown: Irreducible Complexity and Design at the Foundation of Life," Touchstone, 12, nr.4(July/August, 1999) 33-38.

Beierwaltes, Werner, "Der Kommentar zum Liber de Causis als neuplatonisches Element in der Philosophie des Thomas von Aquin," Philosophische Rundschau, 11(1963) 192-215.

The Book of Causes, Dennis J. Brand, tr., Milwaukee, WI: Marquette University Press, 1984.

Bunge, Mario, Causality and Modern Science, New York: Dover, 1979 (Third edition).

Burtt, Edwin A, The Metaphysical Foundations of Modern Science, Garden City, New York: Doubleday, 1954.

Clayton, Philip, God and Contemporary Science, Edinburgh: Edinburgh University Press, 1997.

Couesnongle, Vincent de, "Mesure et causalité dans la 'quarta via'," Revue thomiste, 58(1958) 55-75, 244-284.

D'Ancona Costa, Cristina, "Saint Thomas lecteur du Liber de Causis," in Recherches sur le Liber de Causis, Paris: Vrin, 1995. p.229-258.

De Libera, Alain, "Albert le Grand et Thomas d'Aquin interprètes du Liber de Causis," Revue des sciences philosophiques et théologiques, 74(1990) 347-378.

De Rijk, L.M., "Causation and Participation in Proclus: the Pivotal Role of 'Scope Distinction' in his Metaphysics," in E.P. Bos and P.A. Meijer, eds., On Proclus and his Influence in Medieval Philosophy, Leiden: E.J. Brill, 1992. p.1-34.

Dembski, William, The Design Inference: Eliminating Chance through Small Probabilities, New York and Cambridge: Cambridge University Press, 1998.

Deninger, Johannes G, "Platonische Elemente in Thomas von Aquins Opusculum De ente et essentia," in Kurt Flasch, ed., Parusia: Studien zur Philosophie Platons und zur Problemgeschichte des Platonismus, Frankfurt: Minerva, 1965. p.377-391.

Dewan, Lawrence, O.P., "St. Thomas and the Causality of God's Goodness," Laval théologique et philosophique, 34(1978) 291-304.

Dilley, Frank B., "Does the 'God Who Acts' Really Act?," in Owen C. Thomas, ed., God's Activity in the World: the Contemporary Problem, Chico: Scholars Press, 1983. p.45-60.

Duméry, Henry, "L'Etre et l'Un," in Miscellanea Albert Dondeyne, Leuven: Leuven University Press, 1974. p.331-350.

Einstein, Albert, Out of my Later Years, New York: Wisdom Library, 1950.

Elders, Leon, "Saint Thomas d'Aquin et la métaphysique du Liber de Causis," Revue Thomiste, 89(1989) 427-442.

Fabro, Cornelio, Participation et causalité selon saint Thomas d'Aquin, Louvain: Universitaires de Louvain, 1961.

Farrer, Austin, Faith and Speculation, New York: New York University Press, 1967.

Fay, Thomas A., "Participation: The Transformation of Platonic and Neoplatonic Thought in the Metaphysics of Thomas Aquinas," Divus Thomas, 76(1973) 50-64.

Geiger, L.-B., O.P., La participation dans la philosophie de S. Thomas d'Aquin, Paris: J. Vrin, 1953.

Gersh, Stephen E, KINESIS AKINETOS: A Study of Spiritual Motion in the Philosophy of Proclus, Leiden: E.J. Brill, 1975.

Gilkey, Langdon, "Cosmology, Ontology and the Travail of Biblical Language," in Owen C. Thomas, ed., God's Activity in the World: the Contemporary Problem, Chico: Scholars Press, 1983.

Gilson, Etienne, The Spirit of Medieval Philosophy, New York: P.J. Kenedy & Sons, 1964.

Gwynne, Paul, Special Divine Action: Key Issues in the Contemporary Debate (1965-1995), Rome: Pontificia Universita Gregoriana, 1996.

Hansson, Mats J., Understanding an Act of God, Uppsala: Acta Universitatis Upsaliensis, 1991.

Ho, Joseph chiu yuen, "La doctrine de la participation dans le commentaire de saint Thomas sur le Liber de Causis," Revue philosophique de Louvain, 70(1972) 360-83.

Kaufman, Gordon D., God the Problem, Cambridge, MA: Harvard U. Press, 1972.

Kremer, Klaus, Die neuplatonische Seinsphilosophie und ihre Wirkung auf Thomas von Aquin, Leiden: Brill, 1966.

Kremer, Klaus, "Die Creatio nach Thomas von Aquin und dem Liber de Causis," in Ekklesia: Festschrift für M. Wehr, Trier: Paulinusverlag, 1962. p.321-344.

Mansion, A, "Saint Thomas et le Liber de Causis," Revue Philosophique de Louvain, 53(1955) 54-72.

Mascall, E.L, Christian Theology and Natural Science: Some Questions on their Relations, New York: Ronald Press Co., 1956.

Mooney, Christopher F., S.J., Theology and Scientific Knowledge: Changing Models of God's Presence in the World, Notre Dame, IN: University of Notre Dame Press, 1995.

Muralt, André de, Néoplatonisme et Aristotélisme dans la métaphysique médiévale: analogie, causalité, participation, Paris: J. Vrin, 1995.

Murphy, Nancey, "Divine Action in the Natural Order: Buridan's Ass and Schrödinger's Cat," in Robert John Russell, et al., eds., Chaos and Complexity: Scientific Perspectives on Divine Action, Vatican City State: Vatican Observatory Publications, 1995. p.325-357.

O'Rourke, Fran, Pseudo-Dionysius and the Metaphysics of Aquinas, Leiden: E.J. Brill, 1997.

Pattin, Adriaan, O.M.I., "Autour du Liber de Causis: Quelques réflexions sur la récente littérature," Freiburger Zeitschrift für Philosophie und Theologie, 41(1994) 354-388.

Pattin, Adriaan, O.M.I., ed, Le Liber de causis. Édition établie à l'aide de 90 manuscrits avec introduction et notes, Louvain: Éditions du "Tijdschrift voor Filosofie", 1966.

Peacocke, Arthur, Theology for a Scientific Age: Being and Becoming- Natural, Divine and Human, Minneapolis: Fortress Press, 1993.

Polkinghorne, John, The Faith of a Physicist: Reflections of a Bottom-Up Thinker, Princeton, N.J.: Princeton University Press, 1994

Polkinghorne, John, Science and Providence: God's Interaction with the World, Boston: New Science Library, 1989.

Proclus, The Elements of Theology, E.R. Dodds, tr., Oxford: Clarendon Press, 1963.

Russell, Robert John, "Does the 'God Who Acts' Really Act in Nature?," in Ted Peters, ed., Science and Theology: the New Consonance, Boulder, CO: Westview Press, 1998. p.77-102.

Saffrey, H.D., O.P., "L'état actuel des recherches sur le Liber de Causis comme source de la métaphysique au Moyen Age," in Die Metaphysik im Mittelalter, 2 vols., Berlin: W. de Gryte, 1963. vol. 2. p.267-81.

Saffrey, H.D., O.P., "Allusions antichrétiennes chez Proclus: le diadoque platonicien," Revue des sciences philosophiques et théologiques, 59(1975) 553-563.

Schillebeeckx, Edward, Christ: the Experience of Jesus as Lord, NewYork: Crossroad, 1983.

Schulte, Raphael, "Über Gottes Wirken in Welt und Geschichte," in Weisheit Gottes - Weisheit der Welt: Festschrift für Joseph Kardinal Ratzinger zum 60. Geburtstag, 2 vols., St. Ottilien: Verlag Erzabtei St. Ottilien, 1987. vol. 1. p.137-156.

Shanley, Brian, O.P., "Divine Causation and Human Freedom in Aquinas," American Catholic Philosophical Quarterly, 72(1998) 99-122.

Solignac, A, "La doctrine de l'esse chez saint Thomas est-elle d'origine néoplatonicenne?" Archives de philosophie, 30(1967) 439-452.

Steel, Carlos, "Proclus et Aristote sur la causalité efficiente de l'intellect divin," in Jean Pepin & H.D. Saffrey, eds., Proclus. Lecteur et interprête des Anciens, Paris: Éditions du Centre National de la Recherche Scientifique, 1987. p.213-225.

Sweeney, Leo, S.J., "The Doctrine of Creation in Liber de Causis," in Charles O'Neil, ed., An Etienne Gilson Tribute, Milwaukee: Marquette University Press, 1959. p.271-289.

Taylor, Richard C, "The Kalam fi mahd al-khair (Liber de Causis) in the Islamic Philosophical Milieu," in Pseudo-Aristotle in the Middle Ages, London: University of London, 1986. p.37-52.

Thomas Aquinas, St, Commentary on Aristotle's Physics, Richard J. Blackwell, Richard Spath, and W. Edmund Thirlkel, tr., New Haven: Yale U. Press, 1963.

Thomas Aquinas, St, Commentary on the Book of Causes, Vincent A. Guagliardo, O.P., Charles R. Hess, O.P., and Richard C. Taylor, tr., Washington, D.C.: Catholic University of America Press, 1996.

Thomas Aquinas, Opera omnia ut sunt in Indice Thomistico cum hypertextibus in CD-ROM, cur. Robert Busa, SJ, (Trend, 1996).

Thomas Aquinas, St, Summa theologica, 3 vols., Fathers of the English Dominican Province, tr., New York: Benziger Bros., 1946.

Thomas Aquinas, St., On the Truth of the Catholic Faith (Summa contra Gentiles), 4 vols., Anton C. Pegis, et al., tr., New York: Doubleday, 1955.

Thomas Aquinas, St., Super Librum De Causis Expositio, H.D. Saffrey, O.P., ed., Fribourg: Société Philosophique, 1954.

Tommaso D'Aquino, Commento al Libro delle Cause, Cristina D'Ancona Costa, tr., Milano: Rusconi, 1986.

Torrell, Jean-Pierre, O.P., Saint Thomas Aquinas, Robert Royal, tr., Washington, D.C.: Catholic University of America Press, 1996. vol. 1.

Tracy, Thomas F., "Divine Action, Created Causes, and Human Freedom," in Thomas F. Tracy, ed., The God Who Acts: Philosophical and Theological Explorations, University Park, PA: Pennsylvania State University Press, 1994. p.77-102.

Tracy, Thomas F., God, Action, and Embodiment, Grand Rapids, Mich.: Eerdmans, 1984.

Trouillard, Jean, "'Agir par son être même,' La causalité selon Proclus," Revue des sciences religieuses, 32(1958) 347-357.

Vansteenkiste, C., O.P., "Il Liber de Causis negli scritti di San Tommaso," Angelicum, 35(1958) 325-374.

Velde, Rudi A. Te, Participation and Substantiality in Thomas Aquinas, New York: Brill, 1995.

Wallace, William A., O.P., Causality and Scientific Explanation, 2 vols., Ann Arbor: University of Michigan Press, 1972.

Wallace, William A, O.P., The Modeling of Nature: Philosophy of Science and Philosophy of Nature in Synthesis, Washington, D.C.: Catholuc University of America Press, 1996.

Ward, Keith, Divine Action, London: Collins, 1990.

Weisheipl, James A., O.P., Friar Thomas D'Aquino: his Life, Thought and Works, Washington, D.C.: The Catholic University of America Press, 1983.

Weisheipl, James, O.P., "Thomas' Evaluation of Plato and Aristotle," New Scholasticism, 48(1974) 100-124.

Notes

1. St. Thomas Aquinas, Commentary on The Book of Causes, Vincent A. Guagliardo, OP, Charles R. Hess, OP, and Richard C. Taylor, tr., Washington, D.C.: Catholic University of America Press, 1996, p.4. Hereafter, Commentary. (For the Latin text, see St. Thomas Aquinas, Super Librum De Causis Expositio, H.D. Saffrey, O.P., ed., Fribourg: Société Philosophique, 1954.)

2. Commentary, p.3.

3. St. Thomas Aquinas, Commentary on Aristotle's Physics, Richard J. Blackwell, Richard Spath, and W. Edmund Thirlkel, tr., New Haven: Yale U. Press, 1963, Book 1, lect.1, nr.5.

4. See Aristotle, Physics. II, c.3, (194b 30) in The Basic Works of Aristotle, New York: Random House, 1941.

5. St. Thomas Aquinas, Summa Theologica, New York: Benziger, 1946, I, 44, 3, co.; I, 15, 1; I, 3, 8, ad 2. (Hereafter, ST.) "Freed from its separatist nature, Aquinas fully embraces the Platonist principle of causality and participation: in particular he makes his own much of the vision of the Liber de Causis..." -Fran O'Rourke, Pseudo-Dionysius and the Metaphysics of Aquinas, Leiden: E.J. Brill, 1997, p.127. cf: James Weisheipl, , O.P., "Thomas' Evaluation of Plato and Aristotle," New Scholasticism, 48(1974) 100-124.

6. "Il titolo di questo libro richiama una nozione, 'causa,' che suggerisce al lettore contemporaneo contenuti concettuali per qualche aspetto sostanzialmente diversi da quelli che evocava nel lettore medievale. Difatti per i contemporanei il termine 'causa' indica per lo più la sola idea di consequenzialità necessaria... Per il lettore medievale, invece, accanto all'idea di una connessione di fatto, il concetto di 'causa' trasmette quella di un ordinamento metafisico. ... La causa, in questo modo, è superiore all'effetto; e poiché è principio della sua sussistenza in essere, è principio anche della sua intelligibilità." -Cristina D'Ancona Costa, "Introduzióne," in Tommaso D'Aquino, Commento al Libro delle Cause, Milano: Rusconi, 1986, p.7.

7. Mario Bunge, Causality and Modern Science, New York: Dover, 1979, p.32.

8. See William A. Wallace, O.P., Causality and Scientific Explanation, 2 vols., Ann Arbor: University of Michigan Press, 1972, vol.2, p.246.

9. Edwin A. Burtt, The Metaphysical Foundations of Modern Science, Garden City, New York: Doubleday, 1954, p.30, 98-99, 208-209.

10. Philip Clayton, God and Contemporary Science, Edinburgh: Edinburgh University Press, 1997, p.189.

11. Frank B. Dilley, "Does the 'God Who Acts' Really Act?" in Owen C. Thomas, ed., God's Activity in the World: the Contemporary Problem, Chico: Scholar's Press, 1983, p.54.

12. Albert Einstein, Out of my Later Years, New York: Wisdom Library, 1950, p.32. Keith Ward also observes, "The scientific world-view seems to leave no room for God to act, since everything that happens is determined by scientific laws." Keith Ward, Divine Action, London: Collins, 1990, p.l.

13. Gordon D Kaufman, God the Problem, Cambridge, MA: Harvard U. Press, 1972, p.147.

14. Langdon Gilkey, "Cosmology, Ontology and the Travail of Biblical Language," in Owen C. Thomas, ed., God's Activity in the World: the Contemporary Problem, Chico: Scholar's Press, 1983, p.31

15. John Polkinghorne, Science and Providence: God's Interaction with the World, Boston: New Science Library, 1989, p.31.

16. Robert John Russell, "Does the 'God Who Acts' Really Act in Nature?," in Ted Peters, ed., Science and Theology: the New Consonance, Boulder, CO: Westview Press, 1998, p.89, 94. Similar approaches can be found in Nancey Murphy, "Divine Action in the Natural Order: Buridan's Ass and Schrödinger's Cat," in Robert John Russell, et al., eds., Chaos and Complexity: Scientific Perspectives on Divine Action, Vatican City State: Vatican Observatory Publications, 1995. p.325-357; Christopher F. Mooney, S.J., Theology and Scientific Knowledge: Changing Models of God's Presence in the World, Notre Dame, IN: University of Notre Dame Press, 1995, p.102; Philip Clayton, God and Contemporary Science, p.194-5; and the much earlier work of E.L Mascall, Christian Theology and Natural Science: Some Questions on their Relations, New York: Ronald Press Co., 1956, p.200-1.

17. Philip Clayton, God and Contemporary Science, p.192.

18. Arthur Peacocke, Theology for a Scientific Age: Being and Becoming- Natural, Divine and Human, Minneapolis: Fortress Press, 1993, p.149-151, 160-161, 164.

19. On the inadequacy of a narrow concept of efficient causality to describe God's action in the world, see Raphael Schulte, "Über Gottes Wirken in Welt und Geschichte," in Weisheit Gottes - Weisheit der Welt: Festschrift für Joseph Kardinal Ratzinger zum 60. Geburtstag, St. Ottilien: Verlag Erzabtei St. Ottilien, 1987. vol. 1. p.137-156.

20. "Aristotle, it may be recalled, had conceived of four different types of questions, only one of which was the why-question, and each of these he thought could be answered in causal terms. The varieties of causal explanation he proposed, and which we have seen time and again appearing in different guises throughout this historical account, in our estimation are able to provide more powerful instruments for the acquisition of truth than has been acknowledged in the recent past. ... I have therefore urged an expansion of causal thinking far beyond the narrow domain of Humean causation, to include what contemporary thinkers have spoken of as 'powers', 'inner determiners', and other real 'explanatory factors' that can account for the phenomena being studied by today's scientists." -William A. Wallace, O.P., Causality, vol. 2, p. 240, 326. cf: William A Wallace, O.P., The Modeling of Nature: Philosophy of Science and Philosophy of Nature in Synthesis, Washington, D.C.: Catholuc University of America Press, 1996.

21. Michael J Behe, "Darwin's Breakdown: Irreducible Complexity and Design at the Foundation of Life," Touchstone, 12, nr.4(July/August, 1999) 33-38; Michael Behe, Darwin's Black Box: the Biochemical Challenge to Evolution, New York: Free Press, 1996; William Dembski, The Design Inference: Eliminating Chance through Small Probabilities, New York and Cambridge: Cambridge University Press, 1998.

22. See, for example, D.J. Bartholomew, God of Chance, London: SCM Press, 1984, p.31-2

23. The Arabic text of the work has only 31 propositions, but Latin editions, including that used by Thomas Aquinas in his commentary, divide the fourth proposition of that text into two parts, and come up with a total of 32 propositions. See Dennis J. Brand "Translator's Introduction," in The Book of Causes, (Milwaukee, WI, Marquette University Press, 1984), p.15.

24. D. Brand, "Introduction," p.5-6. See H.-D. Saffrey, "L'état actuel des recherches sur le Liber de Causis comme source de la métaphysique au Moyen Age," in Die Metaphysik im Mittelalter, Berlin: W. de Gryte, 1963, vol. 2. p.267-81. A. Pattin answers Saffrey's arguments in his Le Liber de causis. Édition établie à l'aide de 90 manuscrits avec introduction et notes, Louvain: Éditions du "Tijdschrift voor Filosofie", 1966, p.4-10; and "Autour du Liber de Causis: Quelques réflexions sur la récente littérature," Freiburger Zeitschrift für Philosophie und Theologie 41(1994), especially p. 358-368.

25. H.D. Saffrey, O.P., ed., "Introduction," in Super Librum de Causis Expositio, p.xv. On the evidence for Gerard of Cremona as translator, see Otto Bardenhewer, ed, Die pseudo-aristotelische Schrift Ueber das reine Gute bekannt unter dem Namen Liber de causis, Freiburg im Breisgau: Herder, 1882. p.135-146. Regarding the book's influence in the Islamic world, see Richard C Taylor, "The Kalam fi mahd al-khair (Liber de causis) in the Islamic Philosophical Milieu," in Pseudo-Aristotle in the Middle Ages, London: University of London, 1986, 37-52.

26. "Liber Aristotelis de expositione bonitatis purae." See Dennis Brand, p.1, 4-5; H.D. Saffrey, "Introduction," p.xix.

27. It is interesting that at this time in history, in contrast to the medieval period, it is Platonism rather than Aristotelianism which is viewed with suspicion by Christians. See H.D. Saffrey, "Introduction," p. xxviii: "L'école d'Athènes, frappée en 529 par Justinien, dut femer ses portes pour ne les rouvrir jamais. Au contraire dans ce même temps, à Alexandrie, l'Aristotélisme passait aux mains des chrétiens. Le Platonisme était proscrit, mais de pieuses fraudes en ont sauvé quelques traces. Au moment où le centre intellectuel d'Alexandrie, conquise par les Arabes, se transportera à Bagdad, au milieu du IX^e siècle, il se trouvera des esprits pour faire passer sous le couvert d'Aristote, le meilleur de la pensée platonicienne, qui pouvait encore servir la cause des doctrines chrétiennes ou musulmanes du monothéisme et de la création, et continuer son rôle de ferment de la pensée occidentale."

28. On the "infinitely discrete" anti-Christian allusions in Proclus' writings, see Henri-Dominique, Saffrey O.P., "Allusions antichrétiennes chez Proclus: le diadoque platonicien,"Revue des sciences philosophiques et théologiques, 59(1975) 553-563.

29. Proclus, The Elements of Theology, E.R. Dodds, ed., Oxford: Clarendon Press, 1963, p.260. cf: H.D. Saffrey, "Introduction," p.xxviii.

30. On Proclus' idea of causation, see Stephen E Gersh, KINESIS AKINETOS: A Study of Spiritual Motion in the Philosophy of Proclus, Leiden: E.J. Brill, 1975; and L.M. De Rijk, "Causation and Participation in Proclus: the Pivotal Role of 'Scope Distinction' in his Metaphysics," in E.P. Bos and P.A. Jeijer, eds., On Proclus and his Influence in Medieval Philosophy, Leiden: E.J. Brill, 1992. p.1-34; Jean Trouillard, "'Agir par son être même,' La causalité selon Proclus," Revue des sciences religieuses, 32(1958) 347-357.

31. H.D. Saffrey, "Introduction," p. xxx.

32. Leo Sweeney, S.J, "The Doctrine of Creation in Liber de Causis," in Charles O'Neil, ed., An Etienne Gilson Tribute, Milwaukee: Marquette University Press, 1959, p.283. cf: H.D. Saffrey, "Introduction," p.xxx-xxxi

33. The Book of Causes (1984), Proposition VIII (IX), nr.87, p.28.

34. "The first being is quiescent and is the cause of causes, and, if it gives being to all things, then it gives [being] to them after the mode of creation. However, the First Life gives life to those that are under it not after the mode of creation, but rather after the mode of a form. And similarly, Intelligence gives knowledge and other things to those that are under it only after the mode of a form." -The Book of Causes (1984), Proposition XVII (XVIII), nr.148, p.34.

35. Leo Sweeney, S.J, "The Doctrine," p.288; H.D. Saffrey, "Introduction," p.xxx; A. Pattin, "Autour," p.365. Aquinas remarks on this in his commentary on Propositions 3 and 6. See Commentary, p.23 and 48. On the significance of Aquinas' discoveries regarding the ways that the author of The Book of Causes modified the teaching of Proclus, see Cristina D'Ancona Costa, "Saint Thomas lecteur du Liber de Causis," in Recherches sur le Liber de Causis, Paris: Vrin, 1995, p.229-258.

36. See, e.g., Scriptum super Libros Sententiarum,. I, 4, 1, 2, co. Where not otherwise noted, Aquinas' works are cited from Thomas Aquinas, Opera omnia ut sunt in Indice Thomistico cum hypertextibus in CD-ROM [ITOO], cur. Robert Busa, SJ, (Trend, 1996). For a complete list of references to The Book of Causes in Aquinas' other works, see C. Vansteenkiste, O.P., "Il Liber de Causis negli scritti di San Tommaso,' Angelicum, 35(1958) 325-374. The list is reprinted in Commentary, p.169-178.

37. See Johannes G. Deninger, "Platonische Elemente in Thomas von Aquins Opusculum De ente et essentia," in Kurt Flasch, ed., Parusia: Studien zur Philosophie Platons und zur Problemgeschichte des Platonismus, Frankfurt: Minerva, 1965. p.378.

38. See In Librum Boethii de Trinitate Expositio, ps. 3, q.6, a.1, obj 22; Quaestiones Disputatae de Veritate Q.21,a.5, co. Regarding the meaning of these references to "the philosopher," see Vincent A. Guagliardo, O.P., "Introduction," in Commentary, p.x.

39. Saffrey, "Introduction," p.xvi, xxiv.

40. Aquinas' Commentary probably dates from 1271-1272. See Jean-Pierre Torrell, O.P, Saint Thomas Aquinas, Robert Royal, tr., Washington, D.C.: Catholic University of America Press, 1996. vol. 1, p.223; and James A. Weisheipl, O.P., Friar Thomas D'Aquino: his Life, Thought and Works, Washington, D.C.: The Catholic University of America Press, 1983, p.283-284, 383. On the manuscripts of Aquinas' Commentary and the difficulties involved in their historical interpretation, see A Mansion, "Saint Thomas et le Liber de Causis," Revue Philosophique de Louvain, 53(1955) 54-72.

41. Commentary, Preface, p.4.

42. H.D. Saffrey argues that as Aquinas wrote his commentary, he had three books in front of him: The Book of Causes, the Elements of Theology and a corpus of the works of Dionysius. He cites these works verbatim and other authors from memory. "Introduction," p.xxxvi-xxxvii. Alain de Libera believes that "the critique of Platonism in the name of Aristotle and Dionysius is a leitmotif of Thomas' interpretation of The Book of Causes." - Alain De Libera, "Albert le Grand et Thomas d'Aquin interprètes du Liber de Causis," Revue des sciences philosophiques et théologiques, 74(1990) 370.

43. Our concern will not be to show all of the places that Thomas agrees or differs with The Book of Causes. A more complete account of this can be found in V. Guagliardo, "Introduction," in Commentary, p.xxvi-xxxi.

44. Book of Causes, Proposition 1, in Commentary, p.5. (In this section of this paper, quotations from The Book of Causes are taken from that work as it is published in St. Thomas Aquinas, Commentary.) Of this proposition, Aquinas says: "[S]ince the word 'cause' implies an order of some kind, and in causes we find an ordering of one to another, [the author] introduces as the principle of the entire work that follows a certain proposition concerning the order found in causes." -Preface, Commentary, p.4.

45. Commentary, p.7-8.

46. Commentary, p.10-11.

47. Commentary, p.10.

48. Commentary, p.10.

49. ST I, 5, 4, co.

50. Commentary, p.11.

51. ST I, 5, 4, co.

52. Lawrence Dewan, O.P, "St. Thomas and the Causality of God's Goodness," Laval théologique et philosophique, 34(1978) 301.

53. ST I, 6, 4, co.

54. ST I, 44, 3, co.

55. ST I, 44, 3, co; I, 15, 1, co. and ad 3.

56. St. Thomas Aquinas, On the Truth of the Catholic Faith (Summa contra Gentiles), Anton C. Pegis, et al., tr., New York: Doubleday, 1955, Book 3, c.19, nr.4. (Hereafter, SCG.) cf: SCG, Book 3, c.53; ST I, 4, 3, co.; I, 6, 1, co. See V. de Couesnongle, 'Measure et causalité dans la 'quarta via', Revue Thomiste 58(1958) 278: " Le maximum est affirmé comme cause efficiente et comme cause formelle extrinsèque de l'être gradué. Dans l'ordre de l'être, une cause formelle extrinsèque qui ne serait pas cause efficiente (et vice versa) n'aurait pas de sens. L'esprit passe donc de l'être de 'forme' imparfaite à un être de 'forme' parfaite; pour autaunt la preuve se meut au nivau de la causalité formelle. Mais pour saint 'Thomas,--du moins nous semble-t-il au terme de ces pages,--c'est la causalité efficiente qui est le 'ressort' de la dialectique des degrés: l'être gradué n'est pas par soi, mais par un autre que soi. Les textes parallèles n'invitent donc pas à conclure à l'existence de Dieu en faisant abstraction de la causalité efficiente."

57. ST I, 6, 1, co. It is interesting that Proclus also recognized that, in order to be a final cause, a being must be an efficient cause. In his Commentary on the Parmenides, he therefore criticized Aristotle for making his unmoved mover a final cause but not an efficient cause: "Notice what we habitually say to those who refuse to make intelligible beings the efficient causes of secondary things. How does the heaven desire the divine, if it does not have its origin from it? ... [T]he generated thing desires precisely its origin and its cause, and it is according to its nature that the second turns itself toward the power which produces it and makes it subsist. But when there is no efficient cause and [no] thing which is its effect, what can be done that the one may be desirable for the other? How does it desire it, if it has received nothing [from it]?" -Proclus, Commentary on the Parmenides (922, 1-11), quoted in Carlos Steel, 'Proclus et Aristote sur la causalité efficiente de l'intellect divin,' in Jean Pepin & H.D. Saffrey, eds., Proclus. Lecteur et interprête des Anciens, Paris: Éditions du Centre National de la Recherche Scientifique, 1987. p.215. Proclus' argument for the relation between efficient and final causality hinges on the Neoplatonic idea that an effect reverts to its cause or "turns itself toward the power which produces it." Aquinas here explains why an effect reverts to its cause. The effect seeks its own perfection, and that perfection is similar or proportionate to the effect. But the effect in turn is similar or proportionate to its efficient cause since every cause makes something similar to itself. So, in seeking its own perfection, the effect is seeking the likeness of its efficient cause, and so ultimately seeking or "reverting to" that cause itself.

58. Lawrence Dewan, "St. Thomas," p.303.

59. On the priority of efficient causality in Aquinas' interpretation of the Book of Causes and his goal to "present a collection of teachings of Platonic inspiration,... transposing them to the plane of a philosophy of being," see Leon Elders, "Saint Thomas d'Aquin et la métaphysique du Liber de Causis," Revue Thomiste, 89(1989) 442. On the distinction between Aquinas and both the Aristotelian and Neoplatonic traditions, see Klaus Kremer, Die neuplatonische Seinsphilosophie und ihre Wirkung auf Thomas von Aquin, Leiden: Brill, 1966.

60. Etienne Gilson, The Spirit of Medieval Philosophy, New York: P.J. Kenedy & Sons, 1964, p.75. It is remarkable that Proclus had a similar criticism of Aristotle's unmoved mover. See footnote 57, above.

61. Commentary, Proposition 22, p.130.

62. Commentary, Proposition 22, p.130.

63. Commentary, Proposition 22, p.130.

64. ST I, 45, 3, co.

65. ST I, 45, 3, co.

66. ST I, 45, 3, co. cf: I, 13, 7; I, 8, 1: "As long as a thing has being, God must be present to it, according to its mode of being. But being is innermost in each thing and most fundamentally inherent in all things... Hence it must be that God is in all things, and innermostly."

67. Regarding the kind of rapport that attains between beings that are not of the same order or being, see ST I, 13, 7, co.

68. Commentary, Proposition 9, p.66. The language of participation, however, is applied to creation as well as infusion, as we have seen above. (Commentary, Proposition 22, p.130.)

69. Commentary, Proposition 9, p.70.

70. Commentary, Proposition 23, p.132.

71. Book of Causes, Proposition 1, in Commentary, p.6-7.

72. Commentary, Proposition 1, p.8-9.

73. Commentary, Proposition 1 p.9. See Proclus, The Elements of Theology, E.R. Dodds, tr., Oxford: Clarendon Press, 1963, p.55.

74. See Section 3, above.

75. Commentary, Proposition 3, p.23.

76. Commentary, Proposition 3, p.23.

77. Commentary, Proposition 3, p.26.

78. The Book of Causes, Proposition 3, in Commentary, p.19.

79. Commentary, Proposition 3, p.23. Aquinas further explains the relation between efficient causality and participation in Proposition 9: "[I]f the proper activity of any thing is found in another thing, then that thing must of necessity possess this activity from a participation of the other thing as an effect possesses something from [its] cause. For example, if fired iron performs the proper activity of fire by burning, it is necessary to say that iron possesses this from fire as an effect from [its] cause." -Commentary, p.66. On the notion of participation in Aquinas and the Book of Causes, see Joseph chiu yuen Ho, "La doctrine de la participation dans le commentaire de saint Thomas sur le Liber de Causis," Revue philosophique de Louvain, 70(1972) 360-83. On the relationship between efficient causality and participation in Aquinas, see Thomas A. Fay, "Participation: The Transformation of Platonic and Neoplatonic Thought in the Metaphysics of Thomas Aquinas," Divus Thomas, 76(1973) 50-64; Henry Duméry, "L'Etre et l'Un," in Miscellanea Albert Dondeyne, Leuven: Leuven University Press, 1974, p.333; André de Muralt, Néoplatonisme et Aristotélisme dans la métaphysique médiévale: analogie, causalité, participation, Paris: J. Vrin, 1995, esp. p.100-156; Cornelio Fabro, Participation et causalité selon saint Thomas d'Aquin, Louvain: Universitaires de Louvain, 1961; L.-B., Geiger, O.P., La participation dans la philosophie de S. Thomas d'Aquin, Paris: J. Vrin, 1953, p.370-371.

80. Aquinas sees Avicenna as the major proponent of this view. See Commentary, p. 24, footnote 27.

81. Commentary, Proposition 3, p.24-25.

82. Commentary, Proposition 3, p.25-26

83. On this distinction, see A Solignac, "La doctrine de l'esse chez saint Thomas est-elle d'origine néoplatonicenne?" Archives de philosophie, 30(1967) 439-452; Henry Duméry, "L'Etre," p.331-350.

84. ST I, 3, 4; 44, 1; 45, 5; 104, 1.

85. See Commentary, footnote 5, page 6.

86. Commentary, Proposition 5, p. 40. Louise-Marie Antoniotti, O.P., explains this Neoplatonic view of creation: "Because the same principle cannot be the cause of many effects according to what is proper to each but only according to their common characteristics, there is, beneath God, the first universal cause, a certain number of secondary causes which determine the divine causality in applying it to particular natures." - Louise-Marie Antoniotti, O.P., "La premotion divine: saint Thomas d'Aquin et l'auteur du Liber de Causis," in Atti dell'VIII Congresso Tomistico Internazionale. Studi Tomistici 17, Citta del Vaticano: Libreria Editrice Vaticana, 1982, p.63.

87. Commentary, Proposition 5, p.40-1.

88. Thomas Aquinas, Commentary, Proposition 3, p. 25. See Aquinas' arguments in the Summa Theologica where he quotes a statement from The Book of Causes that "The first of creatures is being," but then interprets the statement to show that the subject of God's creation is not common being, but complete subsisting things (ST I, 45, 4, obj. 1 and ad 1). On the distinction between the understanding of creation in Aquinas and The Book of Causes, see Klaus Kremer, 'Die creatio nach Thomas von Aquin und dem Liber de Causis,' in Ekklesia: Festschrift für M. Wehr, Trier: Paulinusverlag, 1962. p.321-344.

89. Commentary, Proposition 3, p. 23, 27.

90. See Commentary, Proposition 5, p.41; Proposition 9, p. 67. cf: ST I, 45, 5, co.; ST I, 104, 2, co.; cf: ST I, 104, 1; ST I, 65, 4, co.; ST I, 104, 1, co.

91. The Book of Causes, Proposition 6, in Commentary, p.45. This statement about the obscurity of our knowledge of the first cause seems quite obscure itself, so we add the translation of Denis Brand and the Latin from H.D. Saffrey's edition of Aquinas' Commentary. "The First Cause is above all description. And tongues fail to describe it only because they are unable to describe its being, since the First Cause is above every cause and is described only through the second causes that are illuminated by the light of the First Cause." -The Book of Causes (1984), Proposition V (VI), nr.57, p.24. "Causa prima superior est narratione et non deficiunt linguae a narratione eius nisi propter narrationem esse ipsius, quoniam ipsa est super omnem causam et non narratur nisi per causas secundas quae illuminantur a lumine causae primae." -Proposition 6 in Super Librum de Causis Expositio, p.42.

92. Commentary, Proposition 6, p.46. On the unknowability of the first cause in Aquinas and The Book of Causes, see Werner Beierwaltes, "Der Kommentar zum Liber de Causis als neuplatonisches Element in der Philosophie des Thomas von Aquin," Philosophische Rundschau, 11(1963) 210.

93. Commentary, Proposition 6, p.52.

94. Commentary, Proposition 4, p.30; Proposition 6, p.51.

95. Commentary, Proposition 6, p.51-52. The editors explain these distinctions in footnote 38 on p.51: "By this substantive use of the term ens St. Thomas means a being composed of essence, which is itself only potential, and existence (esse), the act whereby something is or exists. Esse is thus the act of existing (actus essendi), distinguishable from the essence in all beings except God, whose essence is 'to be.'"

96. Commentary, Proposition 20, p.122-123.

97. Commentary, Proposition 12, p.90; Proposition 23, p.133. On the transcendence and immanence of divine causality, see Rudi A. Te Velde, Participation and Substantiality in Thomas Aquinas, New York: Brill, 1995, p.166.

98. Commentary, Proposition 20, p.123-124.

99. Proclus, Elements, Proposition 122, as quoted by Aquinas in Commentary, Proposition 20, p.123.

100. Commentary, Proposition 20, p.123.

101. Commentary, Proposition 20, p.123-124.

102. Commentary, Proposition 11, p.83.

103. Commentary, Proposition 11, p.83-85.

104. Book of Causes, Proposition 6, in Commentary, p.45.

105. Commentary, Proposition 6, p.51-52.

106. Commentary, Proposition 6, p.52. See ST I, 4, 3, co.; I, 12, 12; I, 13, 5.

107. Commentary, Proposition 6, p.46-47.

108. Commentary, Proposition 1, p.10.

109. John Polkinghorne, for instance, is perhaps not taking divine transcendence sufficiently into consideration when he characterizes Austin Farrer's account of secondary causality or "double agency" as "an unintelligible kind of theological doublespeak." -J. Polkinghorne, The Faith of a Physicist: Reflections of a Bottom-Up Thinker, Princeton, N.J.: Princeton University Press, 1994, p.81-82. On Austin Farrer's notion of double agency, see Austin Farrer, Faith and Speculation, New York: New York University Press, 1967; Thomas F. Tracy, "Divine Action, Created Causes, and Human Freedom," in Thomas F. Tracy, ed., The God Who Acts: Philosophical and Theological Explorations, University Park, PA: Pennsylvania State University Press, 1994, p.77-102; Paul Gwynne, Special Divine Action: Key Issues in the Contemporary Debate (1965-1995), Rome: Pontificia Universita Gregoriana, 1996, p.83-87; Mats J. Hansson, Understanding an Act of God, Uppsala: Acta Universitatis Upsaliensis, 1991, p.63-66.

110. Thomas Aquinas, Commentarium in Aristotelis libros peri hermeneias, I, lect 14, nr. 22, in Jean T. Oesterle, tr., Aristotle: On Interpretation. Commentary by St. Thomas and Cajetan, Milwaukee: Marquette University Press, 1962, p.118-9. Here it must be remembered that God is the source of creaturely activity to the extent that it is truly actual. Evil, and especially moral evil, however, implies not actuality but privation of actuality which does not have its source in God. See Summa Theologica I-II, q.112, a.3, ad 2, and Scriptum super Libros Sententiarum II, d.37, q.2, a.1, ad 2, and the explanation of the significance of these passages in Edward Schillebeeckx, Christ: the Experience of Jesus as Lord, NewYork: Crossroad, 1983, p.728.

111. Brian Shanley, O.P., "Divine Causation and Human Freedom in Aquinas," American Catholic Philosophical Quarterly, 72(1998) 105

112. Commentary, Proposition 11, p.84.

113. ST I, 105, 6, co. Aquinas also explains that such miraculous events, though "outside" the natural order, are not "against" it: "In natural things something may happen outside [praeter] this natural order... It may... happen by the action of the agent on whom the natural inclination [of a thing] depends; and this is not against [contra] nature, as is clear in the ebb and flow of the tide, which is not against [contra] nature; although it is outside [praeter] the natural movement of water in a downward direction; for it is owning to the influence of a heavenly body, on which the natural inclination of lower bodies depends. Therefore since the order of nature is given to things by God, if he does anything outside [praeter] this order, it is not against [contra] nature." -ST I, 105, 6, ad 1. On significance of this distinction between "praeter" and "contra", see Ralph McInerny, Miracles: a Catholic View, Huntington, Ind: Our Sunday Visitor, 1986, p.130.. See also William P. Alston, "Divine Action: Shadow or Substance?," in The God who Acts: Philosophical and Theological Explorations, University Park, PA: Pennsylvania State University Press, 1994, p.45: "From the point of view of the Christian tradition, it is much better to think of the normal as God's usual way of dealing with His creation, which involves both purely natural causation, much of the time, and special divine causal inputs some of the time. One is no more untoward or 'interfering' or 'interventionist' than another. After al!, this is God's creation. Talk of divine 'intervention' stems from a deist picture of God as 'outside' His creation, making quick forays or incursions from time to time and then retreating to His distant observation post." Finally, see Thomas F Tracy, God, Action, and Embodiment, Grand Rapids, Mich.: Eerdmans, 1984, p.62: "Given God's uniqueness as an agent, the means by which his intentional activity engages his creatures must remain a mystery to us, though the effects of his activity and his intentions in bringing about those effects are at least partially captured, for a particular religious tradition by those descriptions of his actions that are approved or preserved by that tradition. In this case, the theologian can speak with confidence of a mystery that is not reducible to a confusion and deal with imponderables that are not merely a function of conceptual incoherencies."

114. Commentary, Proposition 20, p.124.

115. Rudi A. Te Velde, Participation and Substantiality in Thomas Aquinas, New York: Brill, 1995, p.164-165.

116. Louise-Marie Antoniotti, O.P., "La premotion divine: saint Thomas d'Aquin et l'auteur du Liber de Causis," in Atti dell'VIII Congresso Tomistico Internazionale. Studi Tomistici 17, Citta del Vaticano: Libreria Editrice Vaticana, 1982. p.67.

117. Commentary, Proposition 9, p.70. (See section 4.1.2, above.)

118. Louise-Marie Antoniotti, O.P., "La premotion," p.66.

119. "[O]ur intellect relates to [first causes] as an owl's eye does to sunlight."-Commentary, Preface, p.3.

120. Commentary, Preface, p.3.