Can Leclerc’s Composite Actualities Be Substances?

by John D. Kronen

John D. Kronen is Assistant Professor of Philosophy at the University of St. Thomas in St. Paul, MN 55105. He is the author of two other articles on Suarez’s philosophy of substance and is working on a translation of Disputation XV of Suarez’s Metaphysical Disputations with Jerry Reidi of Macalaster College, St. Paul, MN.

The following article appeared in Process Studies, pp. 25-43, Vol. 21, Number 1, Spring, 1992. Process Studies is published quarterly by the Center for Process Studies, 1325 N. College Ave., Claremont, CA 91711. Used by permission. This material was prepared for Religion Online by Ted and Winnie Brock.


Leclerc’s account of the nature of composite material substances is wrong on three counts: 1. Substantial unity is depicted of the composite; 2. Emergent wholes are presented as more than the sums of their parts; 3. Substances are shown as acquiring new substantial forms.

Substance metaphysics, or the view that the world is composed of individual entities which have properties and are related to each other in various ways, has been under steady attack from various quarters for around 300 years.1 It is a great tribute to its staying power that it has not disappeared completely. Indeed, it has, in many ways, proven itself an extremely adaptable species of metaphysics.2 Its adaptability is so remarkable that the process philosopher Ivor Leclerc has attempted to adapt it to process metaphysics. Since one of the most famous exponents of process thought has called the western notion of substance a chief cause of moral evil and selfishness in the western world (WVR 6), it is astonishing that another famous process philosopher should have tried a reconciliation between process thought, with its emphasis on relations and actions, and Aristotelian substantialism, with its emphasis on things and states of being.3

Leclerc’s desire to reach such a reconciliation springs from his love for the history of philosophy, and for the now neglected branch of philosophy once known as the philosophy of nature4 (PN 19-34). Leclerc thinks it vital for any sound metaphysics that it ground itself on a proper understanding of the nature of physical existence. But according to Leclerc, such a grounding is all the more difficult in modem times, since the very concepts we use to understand nature have become largely subconscious (PN4-8). Since the time of Kant (PN 11-12), explicit and conscious philosophical study of the natural world has been abandoned, and consequently the problems raised in the struggle of modern philosophers (Descartes, Leibniz, and the Atomists) with the traditional Aristotelianism of their day (which found its greatest exponent in the forbidding figure of the Jesuit Francis Suarez), have never been answered.

According to Leclerc, coming up with an answer requires a reinterpretation of the notion of substance that would allow us to regard composite material substances as true substances which are yet composed of smaller substances, down to the ultimate smallest substances, or "minima" (PN 122-24). This, in turn, requires a reinterpretation of the Aristotelian notions of potency, act, and form, in the light of both modem thought (esp. Leibniz), and contemporary process thought. Thus Leclerc says both substance and relation are equally fundamental, since for him substances themselves can consist of the relations which hold between smaller substances.

This paper will attempt an assessment of Leclerc’s radical position, using as a foil the thought of the baroque scholastic, Francis Suarez.5 The latter was picked to fulfill such a function both because he represents the most complete summation of the older Aristotelian theory of substance Leclerc attempts to appropriate and reinterpret, and because he was the most important scholastic figure for the age that Leclerc sees as both the turning point in the history of the philosophy of nature, and as the golden age of such a philosophy, namely, the modern age (PN 194-95).

As will become clear in the course of this paper, I am very skeptical concerning the success of Leclerc’s adaptation of Aristotelian and Scholastic thought. By the time he gets through with such an adaptation, not only has the meaning of terms been pushed to the outer limits of analogy to teeter on the brink of equivocation, but it appears that the very law of non-contradiction itself has been violated. Before attempting to show all this, however, we must first explain Leclerc’s own view, and before attempting to do that, we must first explain a certain central problem in the traditional metaphysics of substance which Leclerc’s view was posited to solve. Only by understanding this problem can we appreciate the subtlety and appeal of Leclerc’s view, however untenable we will ultimately judge it to be.

I: The Problem of the Unity of Material Substances

According to what I shall call "substance metaphysics" the world is made up of distinct beings, each of which has an existence in itself, rather than in another; these beings are called "substances". Everyday examples of such would be a tree, a cat, a human. These beings are characterized by attributes which exist in them, and these attributes are called "accidents" because they "befall" substances. Everyday examples of such would be a cat’s color, a tree’s size, or a person’s idea of justice. Both substances and accidents have essences on the traditional view. The essence of a thing is what it most fundamentally is (e.g. a person, a cat, or a color), and what allows us to put it in a class distinct from other classes (as a dog is in a class with other dogs, that is distinct from the class of cats). A substantial essence will be an essence which gives substantial being of a certain sort, as the soul may be held to give one substantial being as a human. An accidental essence will be an essence which gives only accidental being, as a person’s skin color, for example, or the size of his nose.

In addition to existing in themselves, substances are held by substance metaphysicians to be singular or one in a way that precludes a certain sort of multiplicity. Since substances are the ultimate furniture of the world, so to speak, or what most truly and ultimately exists, they cannot be collections of things. Rather, substances are the fundamental things which are collected. Thus a soldier is a substance, but the army he is a member of is not; it is a collection of substances, each of which, like the soldier, is a person.6 Collections are, in traditional language, called "accidental unities", or aggregates, while individual substances are called "per se" unities, because they are held to be single, complete beings, not heaps of other beings.7

Problems with this traditional view of substance arise when we consider that what we ordinarily take to be substances are in themselves collections, at least in some sense. Thus the soldier we just mentioned is not simple -- he is a composite being, as is apparent even to common sense, since he consists of a number of extended parts: his limbs, organs, tissues, etc. And the knowledge gained from modern science shows that he is further constituted by a wide array of distinct chemicals, atoms, and sub-atomic particles.

Faced with the problem of how to account for the substantial unity of such common sense substances in light of the multiplicity of their extended parts, most philosophers have taken one of the two following positions:

1) They have affirmed the soldier is one substance, and have denied that the parts that compose him are substances. This is the view of Suarez, which I will carefully explain below. Suffice to say here that on this view the parts of the soldier are but a disposition of the matter that is a partial constituent of him. Matter in itself is a pure potency for being (MD 13,5,11), which gets extended, or spread out, we might say, by the accident of quantity, preparing it to receive various forms which actualize its potency or capacity (MD 15, 1, 18-19). In the case of the soldier, the matter is spread out and structured to form a human body, which is quickened and made to be the body of a human by the human soul which informs it. None of the parts of this body, then, are distinct substances; they are accidents of the matter of the human which dispose it for the human form, and which are given their substantial being by the human form or soul (MD 15, 10, 30). They have no other substantial being than that of the human taken as a whole, and if they are severed from the body, and no are no longer actualized by the human soul, they are transformed into new substances which have new, non-human, forms8 (MD 15, 10, 38).

This view names the substantial form "act" and "actuality", since it actualizes the capacity of matter, when properly disposed, for being human, while the matter itself is called a "potency". Matter is thus determinable stuff, and form the intrinsic determiner or actuality of matter, as the shape of a bronze statue is the intrinsic determiner of the bronze, actualizing its capacity to be a statue of such and such a sort.9

2) The second view philosophers have traditionally taken in light of this problem, denies that the human soldier, if by the term "human soldier" we mean to refer to the composite of soul and body, is a single substance, and holds instead that the tiniest parts composing him are. Philosophers who hold this view seem to do so on the ground that it is absurd to think that quantity is, as such, an attribute or accident of a purely potential matter. Instead quantity or extension is the plurality of a number of things existing simultaneously. No single thing can be extended; rather, extension holds only of groups, just as only a group taken together can number five.

The most famous advocate of this point of view is Leibniz, who argued that the only real substances are simple, unextended points, endowed with force. These he named "monads"10 (M 2-3). These monads group themselves together to form the objects of our everyday experience, none of which are single substances, and all of which are aggregates of substances (i.e., of monads)11 (M 70). Thus our soldier is an aggregate, consisting of a self- conscious monad, or mind, which is the soldier’s real self,12 and a body, which is itself a collection of an infinite number of monads, ruled, as it were, by the soldier’s mind (M 62).

Leclerc’s originality consists in the fact that he considers both of the above positions to be partially right, and partially wrong. Both are right in what they affirm and wrong in what they deny. Thus position (1) is right in affirming that the soldier is a substance (PN 122-23), wrong in denying the parts of his body are (PN 128), while position (2) is right in affirming that the parts of the soldier’s body are substances, wrong in denying the soldier as a whole is a substance. In other words Leclerc holds both that a) the soldier is a single, complete substance, and b) the soldier’s parts are complete substances; propositions that Suarez would say are incompatible. How Leclerc tries to reconcile the apparent incompatibility of these two propositions, and why he ultimately fails to do so, are the topics we must now turn to.

Part II: The Dynamic View of Ivor Leclerc

Leclerc develops and articulates his own view of substance in the context of a complex dialectical examination of a number of historical theories. Chief among these are Aristotle’s, Leibniz’s and Whitehead’s. Leclerc gives a very thorough analysis of seventeenth-century thought about composite substances, and contrasts this thought with the Aristotelian theory that preceded it. He then uses Leibniz to oppose most of the tenets of other (less Aristotelian) seventeenth-century thinkers, retaining only one feature of their doctrine. Finally, he modifies Leibniz’s theory of substance by making use of the Aristotelian notions of potency and act. He filters these notions, however, through the sieve of process metaphysics.

In presenting Leclerc’s view we shall briefly summarize the results of his analysis of seventeenth-century thought. We shall then show how Leclerc, by using the philosophy of that century’s own great rebel, Leibniz, criticized most seventeenth-century thought. Finally we shall show how Leclerc attempts to make up for insufficiencies in Leibniz’s view by appealing to an Aristotelianism that is reinterpreted in the light of process thought.

Leclerc sees seventeenth-century thought as of great importance for present concerns, because it was the last century that had a clearly articulated philosophy of nature. As such it still, for better or worse, is the basis of the almost sub-conscious thoughts the modern individual has about the nature of physical reality. Though Leclerc carefully locates his thought in the context of the natural philosophy of the seventeenth century, he modifies it considerably, as we have said, by drawing especially on the insights of Aristotle, the schoolmen, and Leibniz.

Leclerc’s critique of seventeenth-century thought actually arises from a dialectical interchange between that thought and the Aristotelian philosophy of nature that preceded it. This makes perfect sense, because that century’s physical philosophy articulated and formed itself in conscious opposition to Aristotelian physics. It might be helpful in understanding Leclerc’s own views therefore, to list the theses of the Aristotelian view that came under attack in that century, followed by the modern objections to them.

1) Aristotle. Matter is not a complete substance in itself, but a pure capacity, a stuff out of which things are made. It needs to be completed by a substantial form to actually exist (PN 21).

1’) Seventeenth-Century Thought. Matter is a complete substance in itself, needing nothing else to actualize it. Form exists only as a separate substance (i.e., as the human soul) (PN 23).

2) Aristotle. The source of action and of motion is intrinsic to substances. Their very natures demand they act in certain characteristic ways (PN 20).

2’) Seventeenth-Century Thought. The source of action and of motion is entirely outside substances, which are completely passive and inert (PN 24).

3) Aristotle. There are many kinds of change: in quality, quantity and place (PN 23-24).

3’) Seventeenth-Century Thought. There is only one kind of change, change of place (PN 24).

4) Aristotle. The middle-sized objects of our experience, such as dogs, cats, trees, people, etc. are true substances. The components that make them up do not actually exist in them, but are taken up by the higher substantial form of the whole (PN 132).

4’) Seventeenth-Century Thought. Middle-sized objects are not true substances; they are aggregates of true substances, or atoms, which are the tiniest material bodies possible.(PN 37).

5) Aristotle. Extension is an accident of bodies, never their very essence. Qualities are real, and far more important than quantities (PN 144).

5’) Seventeenth-Century Thought. Extension is of the very essence of bodies. Qualities are only phenomenal (PN 58).

Of course, Leclerc is well aware that not all of these seventeenth-century divergencies from Aristotelian physics would be accepted by every seventeenth-century thinker, but he takes them as typical of the time, and further holds that all of them have been very powerful influences on scientific thought since that century.

With the help of Leibniz, Leclerc opposes virtually every one of the fundamental tenets of seventeenth-century thought, with the exception only of the one that says composite substances are composed of simple substances (4’); but even this he greatly modifies, as we shall see, since he also regards composites as true substances, though of a different ontological nature than their components.

Leclerc’s criticism of seventeenth-century thought takes its rise from two tenets of Leibniz; these are that extension is phenomenal only, pertaining to a multitude in relation, and not to any single entity, and that the source of the activity of any physical being is from within. These two Leibnizian tenets allow Leclerc further to deny the seventeenth century’s claim that matter is a complete substance, and that the only sort of change is local. In order to argue against the seventeenth century’s view that compound bodies are not real substances, Leclerc is forced to go beyond Leibniz, however.

Let us first see where Leclerc follows Leibniz, before going into their differences. Leibniz had argued, against most seventeenth-century thinkers, that extension could not be a real attribute of anything, and that all real substances are unextended (M 3). Leibniz’s reason for holding this is because extension 15 a multiplicity of parts, and each part is, itself, something really distinct from the other parts, able to exist on its own from those other parts. And the fact that parts may be strongly joined as, say, two pieces of steel welded together, does not make them any more one than they were before being joined. They are, in reality, no more truly one than individual sheep in a flock are, or a pair of Siamese twins.13 Since every substance is one, and every extended object is many, no substance is extended.

Leibniz had also argued against most seventeenth-century thinkers, that whatever is purely inert, and without any capacity to act, is nothing, so that the source of the action of all things is intrinsic to them. His ultimate metaphysical reason for this is that if this were not the case, no source of action could be found: "If nothing is active by its own nature, there will be nothing active at all, for what reason for activity can there be, if not in the nature of the thing?" (L2: 876)

Leclerc fully agrees with these two assertions of Leibniz, and he further agrees with Leibniz’s arguments for them (PN 84-90). His disagreements with Leibniz, however, start with Leibniz’s conception of the nature of the activity of monads. Leibniz held that no individual substance really acted on any other, and, consequently, that the only action of substances was intrinsic to them, consisting in thinking and willing.

According to Leclerc (and he seems right on this), Leibniz inherited the Neoplatonic views that relations are not real, and that thinking is but the entertaining of pictures of things in the mind. For Leibniz the first of these actually follows from the second. His monads, being unextended and thus not in space, were conceived by him as being minds whose only activity was to mirror in their thought all other monads (M 7-14). Of course, the degree of clarity with which they did so varied, and it was this that distinguished or individuated them. But at the root of all their activity was the same thing -- thought. Thus each monad was a little world reflecting all others, but in itself it was not really related to the others, nor did it act on them.

This latter point is crucial for Leclerc. He thinks, rightly, that the reason the monads are not really related to each other is precisely that they cannot act on each other; and they cannot act on each other because their only activity is the contemplation of the mental images they have of each other (NPE 268-69). Leclerc suggests, however, that such a doctrine is neither warranted nor desirable. It is not warranted because even if one does accept Leibniz’s view that the ultimates are unextended (as Leclerc does) one need not accept that their only activity is thought -- for Leibniz simply assumes this, he never demonstrates it (NPE 267-69). Leclerc seems too hard on Leibniz at this point, for Leibniz attempted to demonstrate that the only activity of monads is mental from his view that transient action is impossible (M 7). His arguments for this, however, seem very weak, as C. D. Broad has powerfully argued (LI 48). At any rate, they have not convinced many philosophers other than Leibniz. Assuming, therefore, Leibniz to be mistaken in thinking transient action is impossible, we can agree with Leclerc that it is an unwarranted assumption that all monads do is think.

But not only is Leibniz’s doctrine that the monads cannot act on each other unwarranted, according to Leclerc; it is also undesirable. If we assume it we cannot explain the nature of things which have structures intelligible only as wholes, such as living beings (PN 117-18). The parts of such beings must be related, and intimately so, according to some overall pattern or structure which will be their substantial form, to use Aristotelian terminology. In making his own contribution to the philosophy of nature, Leclerc seeks to build on Leibniz’s notion that ultimates are I) minima and 2) active, by modifying Leibniz’s view so that it can account for the substantial nature of such organic wholes as plants, men, cats, and even molecules.

To establish a metaphysics which will allow him to do this, Leclerc first seeks to demolish the Neoplatonic notion that all relations are set up by the mind, with its unfortunate consequence that the minima or monads are not related to each other in a way that would allow for the formation of organic wholes which are not mere heaps, but have some character as wholes (PN 146-47). Leclerc’s way of doing this is simple in its basic idea, though its details are complex. He supposes that the minima do act on each other, and not only act but react, in such a way that their composite acting is greater than each or than the acting of each. To see what he means, consider the following example. Consider two substances, A and B. A acts, in some unspecified but real way, on B, affecting B in its being. The act of A on B is already more than just A or B; it is rooted in them, so to speak, but is not a real accident or feature of either individually, for it is a "going out from A and a landing in B." At the same time, according to Leclerc, that A acts on B, B will act on A, for to be really acted on or affected by another thing is in some way to also act on and affect it; there is thus no such thing as absolute potency (NPE 295).

The action produced by the interactings of A and B will be other than A or B, more than they are, and also more than the acting of either A on B, or B on A, taken individually. To explain the action one will have to refer to both, but to both only in relation to each other. This notion of the real interactings of minima on each other is the basis of Leclerc’s doctrine of the nature of the physical existent, and of his view that complex substances literally consist in the actions produced by the interaction of the minima that comprise them (PN 148-50). The emphasis is thus not on the entity of the minima themselves, but on their acting on other minima, according to some pattern or form. The precise nature of this acting we shall presently turn to, but it should be clear at this point that Leclerc’s opinion that a composite substance literally consists of the acting of the minima that compose it, is a very novel view of substance, to say the least, and one which, intuitively, seems fraught with difficulties, since the traditional view of substance is that it is that which acts, not activity or action itself

Having briefly stated the fundamental insight which grounds Leclerc ‘s theory, I wish to examine it in detail. In order to do so, it would be helpful to compare and contrast it with the theory it is most similar to, namely the hylomorphic theory, represented in this paper by Suarez. We can, in this way, see Leclerc’s view as an attempt to mediate between the seventeenth-century thought of Leibniz on the one hand, and the thought of the schoolmen on the other, coming up with a third view that he thinks combines the strength of what is best in both seventeenth-century thought and in scholasticism, while avoiding their weaknesses.

Leclerc appropriates from hylomorphism the act/potency doctrine in order to explain how a compound substance can yet have substantial unity. That the unity of compound material substances is the key problem involved in the account of such substances, Leclerc sees quite clearly.

There is a weighty consensus, from Plato and Aristotle down the ages to Leibniz and Whitehead, that unity must be grounded in substance. This means that in the ultimate and primary sense unity is the unity of substance per se. The unity of an aggregate is not ascribable to the aggregate as a feature of the aggregate per se -- for an aggregate is by definition not a "one" but a plurality -- so there can be a unity only with reference to some or other "observer"; that is, the "unity" of an aggregate is grounded in some substance as an ens rationis. (NPE 295)

Leclerc’s solution to how one can have compounds that are yet single, complete substances, and not heaps or aggregates of substances, like a pile of rocks, is grounded on the old Aristotelian notions of potency and act. Leclerc radically reinterprets these in a relational way, making the unity of a substance to consist, not in a simple actualizing principle (substantial form as act), but in the relational acting of the various substances involved in the constitution of the compound. To see clearly Leclerc’s originality in this regard it will be helpful to remind the reader of the older scholastic view of Suarez, and then to present Leclerc’s solution, noting both its similarities and differences from the older view.

In this matter, Suarez holds that in order for a composite to be "per se" and substantially one, it must be made up of incomplete entities, related to each other as matter, or determinable stuff, to form, or determining act14 (MD 4,3, 8). "Act" here must not be equated with "action"; rather, "act" refers to the intrinsic quality, as it were, that determines the potency of matter to be such and such, in the way that the shape of a piece of clay determines its potentiality to be a certain shape. For Suarez it cannot be the case that both of the entities comprising a composite substance be form, or act, as form is complete and actual in itself, and can only be further completed accidentally, that is, can only be further completed by various accidental attributes existing in it, which do not change it essentially, but only alter it, as a change of the color of a substance, for example, does not make a new substance, but only alters an existing one. Hence the determinable element in a composite substance is the pure potency of matter which is ordered to form as that which substantially completes it.

And thus also this looks to the common reason, that any form which comes to an entity already constituted in act does not make it one per se, but per accidens... and thus it is not able to be a substantial form, but only an accidental one, because a substantial form constitutes a one per se, not per accidens. And the reason is because the substantial form gives being absolutely and essentially and thus it cannot suppose something [already] constituted in simple being, and perfected in a complete essence. Accidental form truly gives secondary being, because it is accidentally joined to a perfected essence. Therefore it is impossible that the subject, which is the material cause of generable things and substantial generation, be a complete substance, and be constituted by a proper and specific form. (MD 13,3,11)

It cannot be overstressed that for Suarez there cannot be more than one substantial form to a composite, because form is act, and act is being, so from two forms two beings, not one, arise (MD 13, 3, 11). Of course, if the forms are accidental there can be many of them in the same substance, provided that they are not essentially contrary (as large and small, for example). But that is because the very nature of accidental forms is to exist in another, and from many accidental forms there arises only an accidental unity (MD 4, 3, 13). Substance, and the substantial form which constitutes substance, have a kind of being, being "in se" which is inimical to existing in another -- hence there is only one substantial form to a composite substance (MD 15, 10). In this way Suarez holds that the composite cannot be constituted by more than one actual principle -- it can only be constituted by a potential principle, matter, and an actual principle, form. Any other actual principle, added to the substantial form, can only be an accidental one (MD 13,3,11).

Three points should be noted concerning this view: (1) The components of a substance cannot be related as substance to substance, and more particularly the potential principle cannot be a substance. It is true that for some scholastics (including Suarez) the human soul, which is the human form and actualizing principle, can be a partial substance having an essential existence of its own (A 1, 12). But the matter, or potential principle, if it is to be given complete essential being through form, and is to share in the form’s existence, cannot naturally exist in and of itself as a substance, else there would be two substances, not one, in the composite15 (EE 2, 3). (2) Form is act, taken not as activity, like thinking or running or speaking, but as actualizing principle of being, as that which forms or makes to be such and such (MD 12, 3, 3). (3) Form is a certain partial entity which confers on matter its essential being, making it to be what it actually is, such as a tree, a pig, or a flower (MD 15,5, 1). It is, as the principle of unity, a part of the substance, but a part which binds the whole into one; in actualizing it gives essential being, and in giving essential being, it of course gives true substantial unity.16 But it could not give unity were it not itself a simple unity. Thus, although the scholastics held that every substance other than God is a composite in some sense, they held that the principle of the being and unity of those substances, the substantial form, is itself a simple act.

Let us turn now from the scholastic theory of Suarez to Leclerc’s theory. What does he accept and what does he reject of the older view? He accepts the notion that the substantial unity of the composite substance can only be explained in terms of the notions of potency and act (PN 126-27). He further accepts that act or actuality is, in some way, the source of the being and therefore of the unity of substances (PN 126-27). He rejects, however, the idea that the component parts of a substance cannot in themselves, and independently of their relation to the composite substance, be true substances (PN 128). In this he accepts the seventeenth-century notion that composite substances are composed of minimal or atomic substances. Further, he rejects the notion that form is an entitative act; rather it is the form or character of a relational activity (PN 137). For Leclerc actuality is thus not what the scholastics would call "first act", or the act that makes a thing to be a certain sort of thing (that by which a flower is a flower, for example); rather it is a process, a change, and an activity. It is a relation between substances, not the intrinsic ground of an independently existing substance. Finally, it is not the same as form, for form, according to Leclerc, is that which determines that activity as having a certain, definite, structure.

We need to examine each of these key points of Leclerc’s theory individually, beginning with the notion that the unity of a composite substance can only be accounted for by recourse to the principles of potency and act. This point is relatively obvious and simple according to Leclerc. For if the constituent substances are not potential with respect to the larger composite substance, if they remain "in every respect fully actual, then a compound substance with them as constituents is impossible" (NPE 305). Therefore in relation to the whole compound unity, the constituent substances must be potential. So far there is agreement between Leclerc and Suarez. Leclerc is not finished yet, however, and it is his next point which is the key to all his divergences from Suarez. For Leclerc does not accept the notion that the constituents of the compound substances must be merely substantial principles having no complete existence of their own; rather he accepts the seventeenth-century notion that compound substances are made up of substances which in themselves remain actual substances, and he even insists that this is necessary in order that they be able to act in such a way as to constitute a compound substance (NPE 305).

This being the case, however, how can they come together to form a single compound substance? Why should they not be regarded as simply a number of substances which are indeed really related in virtue of their mutual acting on each other, but independent with regard to substantial being?

The answer is that Leclerc thinks that relations, if they are founded on real interactions between substances, have enough being to constitute a new substantial unity, and hence a new substance. This in turn is based on Leclerc’s dynamism, on his acceptance of the view that insofar as a thing is active, it is; and insofar as it is, it is one (NPE 300). It is thus that the relational activity of the constituents of the compound substance binds and unifies them into a single substantial being and unity. Leclerc insists over and over again that his theory is different from those of all others before him because it recognizes the reality of relations founded on mutual interacting, and that the action produced by such an interacting transcends the constituents, and indeed emerges as a new substance.

In regard to substances in relation, does their being in relation constitute them "one" in a respect which is not the "oneness" of a substance? The alternatives seem to be either that the relating unifies the acting substances into a one which is a substance transcending but constituted by them, or there is a unity by virtue of the relation, leaving the substances basically diverse. The latter view, however, is unsatisfactory, for either the entities in relation remain a plurality and not a unity, or the relation unites them. But if the relation does unite them, bringing them into one, why is this not to be regarded as a substantial unity? It seems to me that this is essentially a substantial unity (NPE 310).

Leclerc, then, conceives the actuality which binds the composite substance together in a totally different way from the way in which the actuality of the substantial form makes material substances to be one in the Suarecian theory. For, as Leclerc notes, the schoolmen conceived actuality to be the substance in "a final, achieved, and thus static state" (NPE 308). For them actuality was primarily the actuality of being a certain sort of thing; it was not process or change. Thus pure act, or God, though completely actual, was for them also unchanging. 17

Leclerc’s theory, in contrast to the scholastic, static, view of actuality, sees actuality as "the substance in relation… and there can be no relation actualized apart form the acting, the relating. So the substance, and hence the relation actualized must necessarily be the substance en-energia, in act" (NPE 308). For all his borrowing from Aristotle, and for all his disagreements with Whitehead, Leclerc remains a process thinker.

The view that actuality is activity rather than primal act of being leads Leclerc to his final disagreement with the scholastic, and hence Suarecian theory: his notion that form is distinct from actuality. Form for Leclerc is neither act taken as the static first act of the scholastics, nor even act taken as activity, the scholastic second act, but rather the specific character and structure of an activity -- for example, the character of the activity which gives rise to the peculiar geometrical shapes characteristic of different molecules (PN 142-49). It is important to note, however, that form is not to be simply identified with these shapes, for shape, being a characteristic of extension, is phenomenal for Leclerc, not real; it is the result of a relation (or better, of a relating) which is formed or determined in such a way that it gives rise to a specific and a unique shape (PN 142-49).

Part III: The Suarecian Criticism of Leclerc

Having given a detailed examination of Leclerc’s view, we now attempt a criticism of it from the standpoint of the more traditional substance theory of Francis Suarez. The question that Suarez would ask of Leclerc is, of course, whether or not in making the component parts of complex substances themselves substances, Leclerc can use their activity to unify them into one substance. And there is no doubt but that Suarez would answer negatively. His reasons for so answering would be based on three aspects of Leclerc’s view that he would find untenable: (1) the notion that action itself could constitute the substantial form of a complex substance, (2) the notion that there are emergent beings arising from a whole which are not formally in the parts, (3) the notion that minima remain, in themselves, actual substances even while constituting a complex substance. We take up each of these in turn.

(1) Leclerc’s view that formed action can constitute the substantial form of a composite substance is founded on his process view of substance. According to Leclerc, process thinking regards the very existence of substances themselves as a kind of activity, the activity of continually coming to be. For Whitehead, and process thinkers generally, existence is dynamic, and there is no aspect of things which is free from change.

The doctrine Whitehead maintains is that the existence of an actual entity must involve "process." If that be so, then all other senses of existence" will accordingly also have reference to process, for, by the ontological principle, all other forms of existence are derivative from "actual" existence. Whitehead’s doctrine, in his own statement, is that "existence" (in any of its senses) cannot be abstracted from "process." The notions of process" and "existence" presuppose each other. (WM 68-69)

It might be noted here that the notion that existence is a kind of acting, that it is existing, bears some resemblance to the Thomistic notion of the act of existing (esse). Nevertheless, both the Thomistic tradition, and scholasticism in general, distinguished act taken as the completed result of an action, as its perfection, and act taken as the action, or the becoming, by which a completed act comes to be. For Suarez action in the sense of a change is not even an accident of substance, for its whole being is relative to that which it effects.

There only remains this particular difficulty, which in the preceding argument was touched on, concerning the dependence of the substance [upon its cause] and, especially, that [dependence] which is through a mode of creation; for it does not intrinsically constitute a substance, nor does it pertain to its completion; therefore in no way will it be an incomplete substance, nor will it nevertheless be an accident, for the reason touched on, namely, because it is not in a subject. This general difficulty indeed can be said concerning all action or dependency, insofar as these have a special sort of difficulty in that they are not from the subject; concerning which we will expressly speak of below in the disputation concerning action and passion. Now it is briefly said, no dependency, or making, as such, has the nature of an accident with respect to the terminus to which it tends, but it does have a being in such a way that it is indirectly or reductively predicated of its terminus; under which consideration local motion is reductively in the predicament of "where", alteration of "quality", etc... for thus all making as such, is nothing other than its own terminus in incomplete being, as heating is as it were some incomplete heat, and thus concerning the rest. (MD 32, 1, 17)

In refusing to make action a full accident, Suarez asserted the affinity of action with potency; action is the act of potency so far as it is in potency. It is not pure potency, but so long as it is action or movement, neither is it act. It is the in-between of potency to its act, and what is true act, the result of potency, is not in the process of becoming or change; it is the rest at the end of change. It is the product, the effect of change. The painter’s process of coloring a house red is a continual motion of potency to act and it has neither the status of a pure potency nor a complete being; yet absolutely speaking it remains more on the side of potency than act. On the other hand, the redness of the house that is the result of the painter’s action is not in any way a change or a process. It is completed act, it is the act of the redness of the house. 18

If Suarez could not accord an act taken as an action of change even the status of a real accident, but located it in the sphere of potential and relative being, then he surely would not have held that formed action could constitute the substantial being of anything. Yet, whether or not he would be right in this would require a full examination of the differences separating scholastic from process thought on this matter. I will content myself, therefore, by simply noting that if one is to maintain a metaphysical pluralism, one must hold there is a distinction between immanent action and transient action. Immanent action is the action of a living thing whereby it affects its own being in some way. Examples would be digestion in plants, sensation in animals, or thought in humans. Transient action is the action whereby any agent, living or non-living, affects the being of another thing in some way. Examples would be the heating action of fire, or cooling action of water.

Now surely the form of a thing, which constitutes it as what it is, must be an immanent action if it is to be an action. But the action that constitutes Leclerc’s complex substance is not immanent; for it is the unified action of the minima of the complex substance on each other. Should it be objected that it is transient action only with regard to the minima, but immanent action with regard to the complex, we respond that that begs the question, for it presupposes that something could be constituted in its essential being by the transient actions of other beings, which is exactly what needs proof.

(2) The second criticism concerns Leclerc’s insistence that in acting on each other substances produce qualities that are not contained in them separately. Leclerc asserts the notion of emergent properties resulting from action in several places, and he is quite clear that these emergent properties are not mere mixtures of the properties that go to make them up; they are new creations, qualitatively different from their constituents.

Now, the significance of this [the theory of the molecule] is that scientific theory has been employing the concept of an entity which has features, qua molecule, which are not merely the sum of the characters of the constituent atoms. That is to say, the concept of a molecule entails that the entity have a group character dependent upon a group structure, and that this group structure -- and concomitant character -- is something over and above, and not reducible to, the individual characters of the constituents. For there is nothing in the individual natures of the atoms whereby a togetherness with others in a particular pattern or structure should result in a particular character of the group -- for example, that one particular patterned togetherness should have the character of water, another of salt, and so on. It is important to note that the very concept of a geometrical pattern or structure of the group involves going beyond what is entailed in the characters of the atoms individually -- i.e., the geometrical structure of the group is not reducible to the individual extendedness of the atoms. (PN 123)19

Suarez would urge, against the notion that there are emergent properties of a compound which are not simply the mixture of the properties of its constituents, that all the real properties of a composite must be found within its constituents; the essential being of the composite can in no way transcend its constituents as united (MD 36, 3, 7). This is because the distinction between the composite and its constituents can only be one of the inclusive to the included. That is, the whole is compared to each of its constituent parts singly as that which includes that constituent part, plus other parts. But this means that the whole cannot be anything over and above the parts joined together. If it were, the composite substance would be an entity really outside of and distinct from its parts, which is absurd.

From this argument Suarez concludes that whatever real properties there are in the composite must have come from and indeed be in the parts. No new accident or substance could arise from the union of the parts, save those that can be accounted for simply in terms of the union of those parts (MD36, 3, 10). Thus matter as actualized by form is given a determinate "to be" by form, and form is given a subject to act on. But this is accounted for by the parts in union. Form without matter is not complete, nor is matter without form. But there can be no emergent property which is not already seen to be within the matter or the form. If it is objected that the composite is a new entity distinct from form and matter, Suarez answers that it is not an entity distinct from form and matter as joined, and thus that whatever is formal in it, is in the substantial form taken as separate from the union -- there can be no new form over and above the substantial form that arises from the union of form with matter.

What is crucial to note in Suarez’s argument is that he is not saying that there are no attributes characteristic of the composite which are not characteristic of the parts. For example, the power of vision is of the composite animal and not of either the animal’s soul or its body. This is because vision requires a sense organ (arising from the body) and certain non-material sensible powers (arising from the soul). But one can see then that the power of vision arises from the joining of soul and body, in the same way the power to grind wheat arises from the joining of the hardness of a rock with the motive force of a hand. There is no mysterious transcending of the being of the parts in any of this; the properties which arise in the composites are seen to be the result of a simple joining of part to part.

For Leclerc this is not the case; according to him the very substantial form of the composite is not the substantial form of the parts -- it is some new substantial form which transcends them. For Suarez this would be to get something from nothing -- if you start with two substantial forms and join them together, you have two substantial forms joined together, not two, plus a third one arising from their union.

It could be objected that Suarez is here contradicting his expressed opinion that the forms of compounds, and especially of living beings, are essentially distinct from the forms of the elements that comprise them, since compounds have "nobler" qualities than elements, and this requires a nobler form (MD 15, 10, 48). The point, however, is that for Suarez this means the forms of compounds cannot be mixtures of the forms of the elements; they are entirely new forms, which do away with the forms of the elements, and retain those forms only as material dispositions. Thus when a compound is generated from a mixture of elements, the elements, in their mixture, so act on the matter in them, that it becomes disposed for the reception of a new and higher form. On the arrival of this new form, the forms of the elements perish, and only those dispositions they introduced into matter which are necessary for the existence of the new form remain (MD 15, 10, 50). Thus it is for Suarez that the constituent parts of compounds are not the substantial forms of the elements, but matter and the new, more perfect form of the compound.

(3) Now we come to what would be Suarez’s third and final objection to Leclerc, and in it we come to the very heart of the whole question of substantial unity for Suarez. It is an objection that will lead us so deep into his thought that we will find we are carried back to the metaphysically primordial distinction between "is" and "is not’, between "sameness" and "otherness", between "yes" and "no". For the father of metaphysics, Parmenides, being could never be other than what it is -- and since being is always what it is, it cannot change, nor can it be multiplied. The Parmenidian insistence that being is what it is, and is distinct from what it is not, is retained in all the great Greek thinkers. And for the schoolmen the Parmenidian notion is the first principle of metaphysics -- "being is being and it is distinct from non-being".

Suarez, however, like Aristotle, could deny neither multiplicity nor change. He held both that all created things are characterized by attributes distinct from each other, and that all created things change -- in this way they become other than themselves; but, and this is an all important "but", they never become other than themselves qua themselves, but only qua certain accidental features which inhere in them (MD 15, 10, 45). The Aristotelian reply to Parmenides, which does not question Parmenides’ basic principle, is the doctrine of accidents. This doctrine states that everything, so long as it remains what it is, cannot change what it is -- it may, however, change accidentally by becoming the subject of new accidental features, which features do not really change what it is, but add to it.

Nature is taken after the manner of a form, which is said to be a being because something is by it; as by whiteness a thing is white, and by manhood a thing is man. Now it must be borne in mind that if there is a form or nature which does not pertain to the personal being of the subsisting hypostasis, this being is not said to belong to the person simply, but relatively; as to be white is the being of Socrates, not as he is Socrates, but inasmuch as he is white. And there is no reason why this being should not be multiplied in one hypostasis or person; for the being whereby Socrates is white is distinct from the being whereby he is a musician. But the being which belongs to the very hypostasis or person in itself cannot possibly be multiplied in one hypostasis or person, since it is impossible that there should not be one being for one thing. (ST 3,17,2)20

Suarez applies this doctrine rigorously: everything, including accidents themselves, can only change accidentally according to him (MD 15, 10, 45). Thus a shade of the color red, if intensified, is a different shade, and it is not changed, rather it ceases to be and is replaced with a new, specifically distinct color. Red, in virtue of what it is, viz, a certain color, cannot change; it can only change accidentally by becoming the proximate subject for new features which do not alter its essence (what it is). Thus its shape might change, and that would be accidental to it, since it would not alter what it is. Of course an accident can be the immediate subject of another accident, but not the ultimate subject, since all accidents must be grounded in substance.

This leads us to the problem at hand. Suarez insists that if accidental forms can only change accidentally, so much more so substance can only change accidentally (MD 15, 10, 45). A substance already constituted in act through the actualization of matter by a given substantial form, cannot acquire a new substantial form and remain what it is; it can only change accidentally by gaining some added feature that does not alter what it is. Hence Suarez would say that Leclerc’s talk about "new substantial forms supervening on already constituted substances" transgresses the law of non-contradiction. For even accidents cannot change in virtue of what they are; they can only change accidentally. And things change accidentally by acquiring new accidental forms, for a substantial form cannot inhere in any already existing substance; were it to do so, it would be an accident21 (MD 13,3,11). Much more so then, will a substance be able to change only accidentally; i.e., while it remains in being it will only be able to acquire new accidental forms, not new substantial forms.

Along the same lines, but in a slightly different vein, Suarez would insist that a substance can only exist in itself -- it cannot exist in another. To talk of one substance existing in another is to fall into a contradiction. But since a complete substance is a being in act, it can only change accidentally; thus whatever new comes to it will come to it accidentally (MD 13, 3, 16). And since substance cannot be made up of accidents, but only of substantial principles, the very constituents of substances cannot exist in some already completed substance, else they would be accidents (MD 13, 3,16). Thus, though matter is a subject for form, it cannot be the case that form in actuating matter exists in matter as an accident. That is why matter, though a subject, cannot be a complete substance. But Suarez would argue that since the simple substances that comprise Leclerc’s complex substances are complete substances in themselves, the substantial form arising from their complex interactions must exist in them as an accident; for a complete substance can be the subject only of accidents, like every other real essence. Hence the form that informs Leclerc’s minima can only be an accidental form, not a substantial one. But in that case it can only give accidental being.


From the point of view of the traditional substance metaphysics of Francis Suarez, Leclerc’s account of the nature of composite material substances fails. It fails because 1) it makes an accident, namely activity, the principle of substantial unity of the composite, 2) it posits emergent wholes which are more than the sums of their parts, and 3) it allows substances to acquire new substantial forms, a contradiction, since all forms accruing to an already existing substance must be accidental. It seems to me at least that the last of these reasons for why Leclerc’s view fails is the most convincing. Whether Leclerc is right in holding that actions can be substantial principles, or that wholes can be more than the sums of their parts, has not been demonstrated in this paper. All that has been demonstrated is that on Suarez’s more traditional view of substance, Leclerc cannot hold such are the case, and certain non-demonstrative arguments have been given in favor of the traditional view. But Leclerc himself regards substance as that which exists in itself,22 so that it does not seem that any entity which exists in another complete substance or substances could itself be either a substance or a substantial principle, since whatever exists in another complete substance or substances must, by the very definition of substance, be accidental.

Moreover, Leclerc’s own argument that certain intimate actions binding minimal substances together are themselves substantial principles, is very weak, and seems to rest on the assertion that such relations must be substantial because 1) there are composite material substances, and 2) such composites are composed of other, smaller substances. Leclerc thus points out a clear need for action to perform the task of substantially uniting other, smaller substances, but he never really shows, even on his own principles, that it can.

Though Leclerc has not succeeded, however, in giving a plausible account of composite substances, it is still possible that he is correct in holding that composite material objects are tightly organized societies of minimal substances, and it seems to the present writer at least that such a view as this would be very hard for traditional substances metaphysics to disprove. This, however, must be the subject of another paper.



A -- Francis Suarez. De Anima. Opera Omnia edition, ed. C Berton Tom. Paris: Vives, 1861. (Arabic numerals refer, respectively, to book and chapter.)

EE -- Thomas Aquinas. De Ente et Essentia, Trans. Armand Maurer. Toronto, Ontario: The Pontifical Institute of Medieval Studies, 1949. (Arabic numerals refer, respectively, to chapters and paragraphs.)

IRP -- John Wild. Introduction to a Realist Philosophy. New York: Harper and Row, 1948.

LI -- CD. Broad. Leibniz; An Introduction. Cambridge, England: The Cambridge University Press, 1973.

L -- G.W. Leibniz. Leibniz: Philosophical Papers and Letters. 2 vol. Trans. and ed. L.E. Loemker. Chicago, IL: The University of Chicago Press, 1956. (Arabic numerals refer, respectively, to volume and page number.)

MD -- Francis Suarez. Disputationes Metaphysicae. Opera omnia edition, ed. C. Berton Tom. Paris: Vives, 1861. (Arabic numerals refer, respectively, to disputation, section and paragraph. Where there are only two numbers no particular paragraph in the section is being referred to).

M -- G.W. Leibniz. Monadology, in Leibniz: Discourse on Metaphysics, Correspondence with Arnauld, Monadology. Trans. O. R. Montgomery. La Salle, IL:

Open Court, 1902, revised by A. P. Chandler, 1927. (Arabic numerals in the text refer to paragraphs. Arabic numerals preceded by "Montgomery" refer to page numbers in Montgomery’s text.)

NP -- John of St. Thomas. Naturalis Philosophiae. Ed. P. Beato Reiser. Turin, Italy: Marietti, 1820. (Arabic numerals refer, respectively, to chapter and article.)

NPE -- Ivor Leclerc. The Nature of the Physical Existent. New York, NY: The Humanities Press, 1972.

PN -- Ivor Leclerc. The Philosophy of Nature. Washington: The Catholic University of America Press, 1986.

POS -- John Kekes. "Physicalism, the Identity Theory, and the Doctrine of Emergence." The Philosophy of Science 33 (December, 1966): 360-75.

PS 19 -- Reto Luzius Fetz. "Aristotelian and Whiteheadian conceptions of Actuality." Process Studies 19/1 (Spring 1990).

ST -- Thomas Aquinas. Summa Theologica. Trans. the Fathers of the English Dominican Province. Westminster MD: Christian Classics, 1987. (Arabic numerals refer, respectively, to part, question, and article.)

WM -- Ivor Leclerc. Whitehead’s Metaphysics. Bloomington, IN: Indiana University Press, 1975.

WVR -- Charles Hartshorne and Creighton Peden. Whitehead’s View of Reality. New York, NY: The Pilgrim Press, 1981.



1. 1 suppose the first sustained attack on it was made by Hume, but since Hume it has been questioned by thinkers as diverse as A. J. Ayer and Alfred North Whitehead.

2. The revival of interest in the metaphysics of substance has occurred in recent years by philosophers in the analytic camp who are known as "essentialists". Among them should be counted Baruch Brody, David Wiggins, Saul Kripke, and Jorge I. E. Gracia (though the latter has roots in scholasticism as well, and is far more versed in the history of the notion of substance than any of the other figures here listed).

3. It should be noted, however, that others besides Leclerc have held that Whitehead and Aristotle can be reconciled if we look, not to the notion of substance developed in the Categories, but to that developed in the Physics and the Metaphysics. This is the position taken by Reto Luzius Fetz, in "Aristotelian and Whiteheadian Conceptions of Actuality (PS 19). According to Fetz, Aristotle rejects the notion that an entity is a "thing". Suarez is in this respect the exact opposite of Fetz. For Suarez, not only is every substance a "thing" (res), but form and matter, as the components of substance are "things" as well; they are incomplete substances which could exist independently of each other.

4. Leclerc notes here that the philosophical investigation of nature has been so neglected that "today even the very phrase ‘the philosophy of nature’ is apt to have a rather antiquated, even perhaps obsolete, ring" (p. 19).

5. Since Suarez was the major Scholastic of the early modern period, and since one of Leclerc’s heroes, Leibniz, did repeatedly indicate the great influence of Suarez’s metaphysics on his own thought, it is odd that Suarez is not so much as mentioned in Leclerc’s writings. Perhaps Leclerc regards Suarez’s thought as not differing in its fundamentals from that of Aquinas. This is in the main true, but, as I have pointed out elsewhere, Suarez shifts the emphasis in his metaphysics of material substances from the phenomenon of substantial change to the problem of substantial unity, which is precisely the problem that so vexed both Leibniz and Leclerc (For an account of Suarez’s metaphysics of material substances, see my article "The Importance of the Concept of Substantial Unity in Suarez’s Hylomorphism", in the special Suarez volume of the American Catholic Philosophical Quarterly.) There is really no work that I know of that fully examines the ground of the differences between St. Thomas and Suarez. Though they agree on much, their differences are very important; the major ones are as follows:

1) For Suarez matter, form and all non-modal accidents have an entity and existence of their own such that they could be conserved individually by God, while for Aquinas only the composite substance has true entitative existence.

2) For Suarez accidents are joined to a substance by means of an intervening "accidental" mode and substantial form is joined to matter by means of an intervening substantial mode, while in Aquinas no such modes exist.

3) For Suarez substantial essences are made to exist substantially or in themselves by means of a mode of subsistence that they could be stripped of, while Aquinas is silent about such a mode (though some Thomists, especially Cajetan and John of St. Thomas, held a position similar to Suarez’s).

4) For Suarez there is an immediate intellectual knowledge of the particular form of things, while for Aquinas direct knowledge is only of the universal, which gets pinned back, so to speak, on sense particulars via the imagination.

5) For Suarez the actual entity of things is the principle of their individuality, while for Aquinas it is designated matter in the case of material substances, and form in the case of immaterial substances.

6) Finally, for Suarez essence and existence are really the same and only conceptually distinct, even in finite beings, while for Aquinas they are really distinct in all finite beings, and really the same only in God.

This last difference seems to ground almost all the rest (save for the differences concerning knowledge of singulars, and the principle of individuation), and it itself seems to be based on two principles: 1) that any two things that are really distinct can exist apart (Cf. MD 7, 2, 9) and 2) that every real thing is in some way actual, so that there can be limited acts which are not limited by potencies distinct from them (Cf. MD 31, 13, 18). "Consequently, since existence is nothing else than an essence constituted in act, just as an actual essence is formally limited by itself, or by its intrinsic principles, so, too, created existence has limitation from its very essence, not as it is a potency in which it is received, but because, in reality, it is nothing else than the very actual essence itself" (On the Essence of Finite Being as Such. On the Existence of that Essence and their Distinction: Metaphysical Disputation 31. Trans. and with an intro, by Norman J. Wells. [Milwaukee, WI: Marquette University Press], p. 223).

6. On this see especially Leibniz. the Correspondence with Arnauld, letter dated April 30. 1687. para. 15. (Leibniz: Discourse on Metaphysics/Correspondence with Arnauld, and Monadology).

7. For a nice summary of the traditional doctrine of the distinction between accidental unities and per se or essential unities, see Francis Suarez, MD 4, 3.

8. The scholastics were wont to say that "inferior" forms remain in "superior’ composite substances "virtually", by which they seemed to mean that the properties of inferior forms remain in the superior forms they are taken up in, but that the inferior forms themselves perish. Thus Aquinas says "the forms of the elements remain in the mixed body, not actually but virtually. For the proper qualities of the elements remain, though modified, and in them is the power of the elementary forms" (ST., 1,76,4,ad 4).

If I understand him correctly, Lewis S. Ford is very close to this Thomistic view when he conceives of parts of substances as "sub-occasions" rather than "actual occasions" which, however, have their own "persistent properties" (PS 3:109).

9. Suarez also calls matter the first quantity of a thing, since quantity flows from matter, and form its first or substantial quality, since quality flows from form, and since form makes a thing to be of such and such a substantial sort (MD 42, intro., 3).

10. "There must be simple substances because there are composites; for a composite is nothing else than a collection or aggregatum of simple substances. Now, where there are no constituent parts there is possible neither extension, nor form, nor divisibility. These monads are the true atoms of nature, and, in fact, the elements of things" (Montgomery, p.251).

11. "It is evident, then, that every living body has a dominating entelechy, which in animals is the soul. The parts, however, of the living body are full of other living beings, plants and animals, which, in turn, have each one its entelechy or dominating soul" (Montgomery, p. 267).

12. Leibniz wavers on this point, but eventually clearly states that only monads are substances in the true sense (see, for example, the letter to Des Bosse, found in Loemker, Gotfried Wilhelm Leibniz; Philosophical Papers and Letters 2, 1001).

13. Correspondence with Arnauld, letter dated April 30, 1687, para. 14, (Montgomery 190).

14. For Suarez an "ens per se unum" is found either 1) in simple entities which are complete in their nature, or 2) in composite entities which are likewise complete in their nature but are comprised of entities which are not complete in their own nature. These entities are always ordered to each other as something determinable to that which determines it, i.e., as matter to form taken in the broadest sense of potency to act.

15. Though Suarez holds, in opposition to St. Thomas, that matter has a partial existence of its own, and can be conserved by God apart from form, it is still not naturally able to exist without form according to Suarez (MD 13,5,9-11).

16. "Any real whole is simply all the parts in an implicit and unspecified form. All the parts are the whole made explicit and distinct. The idea that the whole is a new entity distinct from the parts arises from a tendency to ignore a certain kind of part that enters into the essential composition of any natural entity -- its form or structure. The parts which impress us most obviously are the integral, quantitative parts of a thing. These are called integral because each of them is a whole which can exist apart from the rest.

"If a physical thing were made up exclusively of parts of this kind it would not be essentially one, but only one by accident, like a heap of rocks piled up together. After we have analyzed a thing in this purely quantitative way we often get a dim sense of the underlying unity which binds these quantitative parts into one entity of a certain kind. We realize that there is something more there than a mere agglomeration of quantitative parts. But this something more is not the whole. It is another, more basic kind of part, the substantial form, or structure, which determines the matter from which the thing has evolved and spreads out the quantitative parts in a unitary pattern. Matter and form are the essential physical parts of any natural entity". (IRP 295)

17. "From what precedes, it is shown that God is altogether immutable. First, because it was shown above that there is some first being, whom we call God; and that this first being must be pure act, without the admixture of any potentiality, for the reason that, absolutely, potentiality is posterior to act. Now everything which is in any way changed, is in some way in potentiality. Hence it is evident that it is impossible for God to be in any way changeable". (ST. 1, 9, 1)

18. John of St. Thomas says that motion is a kind of "imperfect act", and that a thing in motion is "partially in act, partially in potency." It is in act relative to the starting point which is moved; for when something is moved it begins to be actualized in a certain way. It is partially in potency, however, for the act of motion is an imperfect act which continually tends to the perfect act which is its terminus or completion (NP 14,1).

19. Some philosophers have criticized the notion of emergent properties by arguing that, in order for a truly new property to emerge, it would have to be logically impossible to predict its existence, prior to its emergence. But they regard such a claim as highly dubious (POS 360-75). The strength of this criticism of emergentism is based upon the naturalistic assumption that all emergent properties must somehow come from a structuring of material substances that existed prior to the emergence. If we grant the deterministic hypothesis that all bodies follow certain physical laws, then it has to be asserted that it would be at least logically possible to predict the emergence of emergent properties from the law-guided interaction of smaller bodies.

Such a criticism, therefore, seems to be very telling against Leclerc, since he holds that emergent properties and substances arise from the complex interaction and structuring of smaller substances. Suarez, on the other hand, does not hold this to be true. For him form is not a structure, but an entity and an act. Therefore any emergent properties and substances would not arise form a complex ordering of smaller substances. They could only arise from the action of a substance that had a degree of being and act as great, or greater, than the substances to emerge. Thus the whole evolutionary notion that higher forms can come from a structuring of lower forms, is implicitly denied by Suarecian metaphysics.

20. English Dominican Province translation, p.2118.

21. That is why, for Suarez, there are modes which are substantial. For the mode of subsistence, which makes a nature capable of substantially existing to actually substantially exist, cannot be an accident, since it helps constitute the substance as a substance. Thus as a completer of the substantial being of a thing, it is not an accident, which is to say, it does not exist in an already constituted being.

22. At least I assume he does, though it is true that he does not talk that much about substance as that which exists in itself, preferring to focus on it as that which is one, and which is a center of action. But certainly in appropriating Aristotle and Leibniz, Leclerc could not have failed to be aware of substance as that which exists in itself, nor, I think, could he deny that any substance, whether minimal or composite, is distinguished from properties by having such a mode of being.