SOURCE: "Ockham on the Possibility of a Better World," Mediaeval Studies, Vol. XXXVIII, 1976, pp. 291-312.

[In the following essay, Maurer discusses Ockham's views on the limitations of God's powers and compares these views with those held by other theologians, including St. Thomas.]

In his William James lectures, published under the title The Great Chain of Being, Arthur Lovejoy formulated 'the Principle of Plenitude' which he found latent in the philosophy of Plato. This Platonic principle asserts that the universe is full of all conceivable kinds of living things; 'that no genuine potentiality of being can remain unfulfilled, that the extent and abundance of the creation must be as great as the possibility of existence and commensurate with the productive capacity of a "perfect" and inexhaustible Source…'¹ According to Lovejoy, this principle of plenitude passed through Neoplatonism into the theology and cosmology of medieval Christendom, and from there it had an enormous impact on modern Western thought. It was this principle, for example, that led Leibniz to affirm that this is the best of all possible worlds. For if God, the creative source of the world, is all-good and perfect, he cannot fail to have produced all conceivable forms of being, from the highest to the lowest, and to have fashioned them in the best possible manner.²

Lovejoy further argued that this principle, introduced into medieval thought especially by St. Augustine and Dionysius, came into conflict with the Christian doctrine of the freedom and omnipotence of the Creator God. The Platonic view of the necessary diffusion of the divine goodness to the full range of its power and the Christian dogma of the freedom of God in creation produced an internal strain in medieval theology. St. Thomas Aquinas was especially criticized by Lovejoy for affirming the principle of plenitude 'quite unequivocally and unqualifiedly', while at the same time holding that 'though the divine intellect conceives of an infinity of possible things, the divine will does not choose them all; and the existence of finite things is therefore contingent and the number of their kinds is arbitrary'.³ The only medieval schoolmen, Lovejoy contended, for whom this conflict of ideas did not arise were the 'extreme anti-rationalists', particularly the Scotists and William of Ockham. These men 'held the arbitrary and inscrutable will of the deity to be the sole ground of all distinctions of value'.⁴ Consequently they posited no rational basis of the goodness of creatures but solely the will of God. As a consequence of their voluntarism, they maintained that 'the world contained whatever it had pleased its Maker to put into it; but what sort of creatures, or how many of them, this might mean, no man had any means of judging, except by experience or revelation'.⁵

The conflict of ideas that Lovejoy alleged to have occurred in St. Thomas' thought through his acceptance of the principle of plenitude is not our present concern. It has been convincingly shown that this conflict is not really present in Thomism but is of Lovejoy's own making.⁶ Unlike the Neoplatonists, St. Thomas did not hold that the world emanated necessarily from its divine source, but rather that it was created by a self-sufficient and autonomous God, who out of his goodness and generosity freely willed to share his perfection with creatures. The only necessary object of God's will is himself; he wills creatures not because of any need on his part but as a free expression of his goodness. Neither do we intend to discuss the supposed anti-rationalism of Duns Scotus and his followers. Recent studies have shown that according to Scotus there is nothing irrational in the works of God; that in fact he assigned a central role to the divine intellect in determining good and evil.⁷ This paper focuses rather on the case of William of Ockham. Did he in fact reject the principle of plenitude, and if so, on what grounds: philosophical or theological? More particularly, what were his views on the possibility of a better world? Could God create a variety of worlds the same or different from our own, and better than ours? The answers to these questions reveal Ockham as both a theologian and a philosopher, anxious to maintain the Christian truth of the freedom and omnipotence of God, but at the same time careful to do justice to the rational claims of the philosophers who uphold the principle of plenitude.

I

In the course of commenting on the Sentences of Peter Lombard, Ockham reached the point where the Lombard treats of the power and omnipotence of God. The Lombard takes the orthodox Christian stand that God is all-powerful, and in this connection he criticizes theologians such as Abelard, who is his view restricted the power of God by denying that he can create things he has not created or make them better than he has made them. Of course, God could not beget a Son better than the one he did, as St. Augustine correctly points out, but this is because the Son is equal to the Father. But when it is a question of creatures, who are not equal to God or consubstantial with him, he can make others better than those he has created, and he can make those he has created better than they now are.⁸

On the occasion of these remarks of Peter Lombard, his medieval commentators were accustomed to discuss at length problems concerning God's power to create, the range of his creative power, his freedom to create or not create, and the possibility of his creating a better world. Ockham follows this tradition with a series of Questions on the divine power, two of which are especially important for his views on the principle of plenitude. They are: Can God make things he has not made nor will make? (1 Sent. 43, 1), and: Can God produce a world better than this world? (1 Sent. 44, 1).

In his discussion of the first question, Ockham begins by assuming that God is the efficient cause of things.⁹ The assumption is obviously necessary, for if God were not their efficient cause there would be no point in inquiring whether he can make something he has not made nor will make. Now this assumption is not groundless, in Ockham's view, for it rests not only on the Christian faith but also on the teaching of philosophers such as Aristotle. In his early work, the commentary on the Sentences, Ockham interprets Aristotle as holding that God is the efficient cause of the celestial Intelligences and through them the remote cause of all other things.¹⁰ He rejects the opposing interpretation, that God is not the efficient cause of the world but only its final cause, moving it solely as an object of love.¹¹

Ockham's reading of Aristotle at this early stage was clearly influenced by Duns Scotus and, before him, by Avicenna. Like Scotus, Ockham thought that according to the mind of Aristotle God is the efficient cause of the total being of the Intelligences, who in turn produced the sublunar world.¹² The obvious objection to this Neoplatonic understanding of Aristotle is that he defines an efficient cause as 'the source of the beginning of motion'.¹³ Since God does not bring the Intelligences into being by moving or changing matter but by producing their total being, they cannot be efficiently produced by God. Ockham meets this difficulty by distinguishing between two Aristotelian uses of the term 'efficient cause'. In one sense an efficient cause brings about its effect by moving or changing matter; in another sense it is 'that at whose existence there follows the existence of something else'. In this second meaning of the term God can be the efficient cause of the Intelligences, since they are produced not by motion but by creation.¹⁴

The distinction between two kinds of efficient cause, one of which is a principle of motion or change and the other a principle of being, originated not with Aristotle but with Avicenna.¹⁵ The distinction was well known among thirteenth century schoolmen. Ockham inherited it from them, reworded it in terms of his own sequential notion of cause, and used it in his interpretation of the causal power of God when commenting on the Sentences.

Later, in his Quodlibets, Ockham abandoned this rendering of Aristotle in favor of the Averroistic view that God is only the final cause of the world. When Ockham wrote this work he no longer believed that according to Aristotle God is the immediate efficient cause of the separated substances, and through them the remote efficient cause of the sublunar world. Rather, it was Aristotle's mind that 'the Primary Being is the final, but not the efficient cause of other things, because he [i.e. Aristotle] holds that the heavenly bodies, with other lower causes, produce these inferior beings'.¹⁶ The Avicennian interpretation of Aristotle in the commentary on the Sentences has given way, in the Quodlibets, to the Averroistic notion that God causes the world only as an object of desire or love.

Both in the commentary on the Sentences and the Quodlibets Ockham strictly limits the power of human reason to prove convincingly anything about God's causal relation with the world. He denies that natural reason can prove that God is the immediate efficient cause of all things; indeed that he is the efficient cause of any effect. No adequate proof can be given that there are other effects than generable and corruptible beings, and their efficient causes are the natural bodies in the sublunar world and the heavenly bodies; and there is no adequate proof that the heavenly bodies, or the separate substances, have an efficient cause. It cannot even be proved that God is the remote or partial cause of any effect. Only persuasive arguments can be offered that God is the efficient or moving cause of some effect. It can be argued, for example, that if God produced nothing his existence would be useless.¹⁷

Accordingly, in the discussion whether God can make things he has not made or will not make, it must be assumed (supponendum est) that God is the efficient cause of things. The arguments of the philosophers, based on natural reason, are no more than persuasions of this truth; it is known with certainty only by faith.

Assuming that God is the efficient cause of the world, can natural reason prove that he produced it as a free and contingent cause? On this point Ockham's interpretation of the philosophers does not waver. It was their mind, he says, that God is not a free or contingent cause of the world, but rather than he produced it naturally. Even though the world issued from God acting through intellect and will, he caused the world by necessity of his nature (per necessitatem naturae). Moreover, Ockham does not think that human reason can conclusively disprove this position of the philosophers. All the arguments of St. Thomas and Duns Scotus to the contrary he rejects as inconclusive.¹⁸

In his De potentia Dei 3.15, St. Thomas gives four reasons for holding 'that God brought creatures into being by no natural necessity but by the free choice of his will (ex libero arbitrio suae voluntatis)'. The first argument is based on the premise that the universe as a whole is directed towards an end, for otherwise everything in it would happen by chance. Hence God had some end in view in the production of creatures. Could he have produced it acting through his nature and not through his will? No, for a natural agent does not determine the end for which it acts. It must be directed to an end predetermined by an intelligent and voluntary agent, which in the case of the universe can only be God. So God directs the universe to its end through his will, and consequently he produced creatures through his will and not by necessity of nature.

The second Thomistic proof also stresses the difference between a natural and voluntary agent. A natural agent is limited to produce one effect equal to itself, unless there is some defect in its active power or in the recipient of the effect. Now far from being defective, the divine power is infinite. Only one 'effect' proceeds from it naturally, namely the Son, who is equal to the Father. Hence creatures, which are unequal to the divine power, proceed from the divine will.

The third argument of St. Thomas is based on the fact that an effect preexists in its cause according to the mode of being of the cause. Since God is an intellect, creatures must preexist in him as in an intellect. But what exists in an intellect can be produced only by means of the will. Consequently creatures proceed from God by means of his will.

The fourth argument also presupposes that God is an intelligent agent. Now his actions must be understood as immanent operations, like understanding and willing, not as transient actions such as heating or moving. The reason for this is the identity of the divine operations and the divine essence, which always remains within God and does not proceed outside of him. Hence everything God creates outside himself is created by the divine knowledge and will.

All these arguments lead to the same conclusion, in St. Thomas' view: 'Therefore it is necessary to say that every creature proceeded from God through his will and not through necessity of his nature'.

After faithfully summarizing these Thomistic arguments, Ockham hastens to add that all of them are inconclusive. They prove that God produced creatures by his will, but they do not establish that this operation of willing was free and contingent. God may produce creatures through his will, as a voluntary agent, and yet produce them naturally and necessarily. Does not St. Thomas himself hold that the will acts in two ways, naturally and freely? Thus he says that the will wills the end naturally and the means to the end freely and contingently.¹⁹ Hence, the fact that God acts through his will does not entail that he does not act through necessity of nature. This is confirmed by the fact that philosophers like Aristotle held that the first cause acts through intellect and will, and yet that it acts by necessity of nature. And does not St. Thomas himself maintain that the Holy Spirit proceeds from the Father through the divine will and yet naturally and necessarily? There is no contradiction, then, in God's producing creatures through his will and yet through necessity of nature.²⁰

Ockham's criticism of the first Thomistic argument pinpoints the weakness he finds in all of them. Even though the divine will directs the universe to its end, it does not follow that it has ordained this end freely and contingently. St. Thomas contends that the will wills what is ordained to the end contingently and freely, even though it wills the end necessarily. While necessarily willing himself as the end, God wills creatures freely because they are ordained to that end. But Ock-ham insists that this explanation is insufficient, 'because it has not been adequately proved that the divine will wills contingently what is ordained to an end, and yet this is in special need of proof'²¹.

Accordingly, in Ockham's view St. Thomas has failed to prove the freedom of God as a creator. He has not demonstrated beyond all doubt that God acted freely and contingently in his production of the universe. For a cause to act freely and contingently, nothing can impede its action, and, after equally regarding several options, it produces one and not the other.²² But according to an unbeliever such as Aristotle this is not the way God is related to the universe. The unbeliever would say that God immediately and equally regards everything producible, but that he necessarily produces the first Intelligence, and by means of it he produces other things, or that the first Intelligence itself produces them. Only if it could be demonstrated by natural reason that God created the universe with a beginning in time (de novo), freely choosing one creature in preference to another possible one, could one prove contingency in him. But no adequate proof of this is possible.²³

If it is impossible to demonstrate contingency in God in the Thomistic manner, by considering the nature of the divine will, can this be done beginning with contingency in things? This is the method of Duns Scotus. The fact that contingent events occur in nature is proof to him that the first cause acts contingently. If the first cause produced its effect necessarily, this effect, acting as a second cause, would in turn produce a necessary effect, and so on for the whole series of causes. So the whole chain of primary and secondary causes would act necessarily, with the result that nothing would happen contingently. Since second causes cause only through the power of the first cause, the fact that they do cause contingently is proof of the contingency of the first cause.

The same conclusion can be drawn from the existence of evil in the world. A necessary cause, Scotus argues, produces its effect in the recipient to the greatest possible extent. Now the effect of the first cause is goodness and perfection. Hence, if the first cause acted necessarily, it would produce the greatest possible amount of goodness in things, and there would be no evil in them. Moreover, the existence of second causes itself argues against the necessary causality of the first cause. An agent acting necessarily acts to the limit of its power (causa necessario agens agit secundum ultimum potentiae suae). Consequently, if the first cause acts necessarily, it produces everything it can produce. Now it can produce everything producible. Therefore, in the event that the first cause acted necessarily, there would be no second causes.²⁴

In a note appended to these arguments Scotus concedes that they would not convince the philosophers (non valent contra philosophos).²⁵ Ockham readily agrees that they are inconclusive from the philosophical point of view. It cannot be evidently proved that because something occurs contingently the first cause acts contingently. The philosophers would reply that the contingency of the effect may result from the contingency of the action of some creature, such as the activity of the created will. The will is a contingent cause, according to the philosophers, and however much other causes may act naturally, when it concurs with them the resultant effect is contingent. The fact that the will is moved or conserved by a necessary first cause does not necessitate its action; it may be left free to act or not to act.²⁶

The concurrence of the will may also account for evil in the world. We need not suppose that the first cause is the immediate and total cause of everything, and hence that evil is to be imputed to it; the created will has a role in many effects, and evil may reside in it, not in the divine will.²⁷ In general, to prove that secondary causes have no part in causation, one would have to demonstrate by natural reason, in opposition to the philosophers, that God, acting by himself, can cause everything producible, or that he immediately concurs in its production. But neither of these is susceptible of proof.²⁸ By 'proof' in this context Ockham means a strict demonstration or 'sufficient proof', which would dispell all doubt and settle the matter philosophically. He grants that persuasive arguments can be given that God is the immediate cause of all things, and that he is a free and contingent cause, but these do not amount to demonstrations.²⁹ Human reason simply cannot disprove the opposite thesis of the philosophers, that God, as the first cause, stands in necessary relation to his effects, and that these effects flow from him in hierarchical order, from the first Intelligence, who proceeds immediately from him, to the lowest material bodies in the sublunar world. From the standpoint of natural reason, this world of the philosophers is entirely plausible. This world constitutes a 'great chain of being', to use Lovejoy's phrase, flowing from the first cause as naturally and necessarily as effects from the sun.

Of course, to Ockham the Christian theologian, this is not the truth of the matter. For this we must turn to the faith, which teaches that God is a cause that acts contigently, and that he can produce the world of generable and corruptible bodies immediately and totally. And because God is a contingent cause, he is not limited to produce creatures as he has in fact done. He can make some that he has not made; for instance, he can produce an infinity of souls, though in fact he will create only a finite number.³⁰ Can he create more worlds than he actually has created, worlds different from, and better than, our own? It is to this question that we now turn.

II

Before answering the question whether God can create a better world, Ockham clarifies the meaning of the terms 'world' and 'better'. A world can be understood in two senses: 1) as the total aggregate of all creatures, whether substances or accidents, or 2) as a whole composed of a multitude of things contained under one body and the body containing them. In the second sense 'world' can be taken precisely for its substantial parts or indifferently for everything contained in it. Ockham specifies that in the present discussion he is using the term 'world' to mean 'precisely one universe composed as it were of parts that are substances, not as including accidents with substance'.³¹

The second sense of the term 'world' is the one familiar to medieval physics through the works of Aristotle. This cosmos was a vast but finite sphere whose outermost limit was the sphere of the fixed stars; within this sphere were contained the planetary spheres, which in turn enclosed the sublunar world of the four elements, with the spherical earth at the center. Ockham's second description of this world is close to that of Richard of Middleton, which runs as follows: 'I call the universe the collection of creatures contained within one surface—which is contained by no other surface within that universe—including also the surface that contains these creatures.'³² Richard of Middleton's specification that the surface of the sphere containing the universe is not itself contained within the surface of another sphere rules out the hypothesis that our universe might be encased in another; that beyond the outermost sphere that limits our world there might be another world contained in another sphere far distant from that which encircles our own. This hypothesis of several worlds, one included in another like layers of an onion, was raised and rejected by William of Auvergne on the ground that the outermost sphere of the second world, enveloping and containing the heavens of that world, would also contain the outermost sphere of our world, and thus it would constitute but one world. The supposed two worlds would be contiguous, one enveloped in the other, with no void separating them, for Aristotle proved convincingly that there is no void in nature.³³

Against this background, Ockham's second definition of a world as 'a whole composed of a multitude of things contained under one body and the body containing them' becomes clearer. The containing body is the outermost sphere of the universe that envelops and contains the heavens and the earth. Properly speaking, the parts included in the universe are its substances, not its accidental properties. There are qualities in the universe really distinct from substances, but these accidents are not contained in the universe as principal parts but as modifications of substances.

What is meant by asking whether God can create a 'better' world? One thing can be better than another essentially or accidentally. A universe essentially better than the present one would be different from it in species and not only in number; that is, it would contain individuals of more perfect species than those in our present world. A universe accidentally better would contain individuals of the same species as ours but their goodness would be heightened.³⁴

Having clarified the terms of the question, Ockham proceeds to answer it. He holds it as possible that God can produce another universe substantially or essentially better that ours. He sees no compelling reason why God cannot create substances more perfect in species than any he has created, and this to infinity. Can he not increase the perfection of a quality, such as grace, without limit? Why can he not increase the goodness of individuals to the point where they constitute a new and better species? Even if one maintains that there is a limit to the perfection of a creature, so that there is a most perfect substance possible for God to create, it can still be held as probably true that God can create another world distinct in species from our own, and hence substantially better than ours.

For confirmation of this Ockham appeals to both St. Augustine and Peter Lombard. According to St. Augustine, God could have made a man who could neither sin nor will to sin and if he did there can be no doubt that he would be a better man than ourselves. Ockham, for his part, contends that he would not only be better but he would belong to a different and higher species of man. The individuals in our human species are able to sin and will to sin. This he considers to be a defining property of our species, and hence it cannot be formally repugnant to any of the individuals in it. If there are individuals who cannot sin, they must belong to an infima species of man different from ours. It follows that if God created such individuals, the universe in which they lived would belong to a different and better species than our own.³⁵

An objection that readily occurs to a Christian is that Christ could not sin, and yet he belonged to the same human infima species as we who can sin. Ockham replies that Christ's incapacity to sin was due to the fact that he possessed the divine nature. Sin was incompatible with the divine Word; it was not incompatible with the human nature united to the Word. If Christ's human nature were separated from the Word, it could sin.³⁶

Ockham's hypothesis of a human nature specifically different from our own runs counter to the usual notion that man is an infima species. How can there be a species of man different from the one we know? Ockham hopes to show the possibility by clarifying the meaning of the term 'man'. In one sense it means a composite of a body and an intellectual nature. Taken in this broad sense, man does not constitute a species specialissima or infima species. In this meaning of the term there could be a man who is by nature incapable of sinning, but he would not belong to the same species as the man who can sin. In another sense, 'man' means a composite of a body and an intellectual soul such as we have. Thus understood, man is an infima species, and this human species would not contain the hypothetical man who is incapable of sinning.³⁷

It is at least probable, therefore, that God could create another world better than the present one and specifically different from it. This better world would contain things of different species, and a greater number of species, than our world. God could also create a better world that is only numerically different from ours. Nothing prevents him from creating an infinite number of individuals of the same species and nature as those existing in our world; nor is he restricted to creating them within the confines of our world. He could produce them outside our world and form another world from them, just as he has already formed our world from the things he has created.³⁸

The hypothesis of a plurality of worlds was not new in Ockham's day; it was debated throughout the thirteenth century in the wake of the translation of Aristotle's works into Latin. The scholastics could then read his arguments that there can be only one world. If there were a number of worlds, Aristotle reasoned, they would contain elements of the same nature as ours; otherwise they would be worlds in name only. They would be equivocally the same as our world. Now, each of the four elements has its proper place. For example, earth is at the center and fire is at the circumference of our world. When they are removed from these places they naturally tend to return to them: earth naturally moves downwards to the center and fire naturally moves upwards to the circumference. On the supposition of a plurality of worlds, the particles of earth in the worlds outside our own would naturally move to our center, and their fire would move to our circumference. If they did not, they would naturally move away from the center and circumference of our world, which is contrary to their nature. Hence there cannot be many worlds.³⁹

The possibility remains that there are many worlds, each with its own center and circumference. On this hypothesis, earth in each of them would always move to the center and fire to the circumference, but to numerically different centers and circumferences. Individual particles of the same species would then naturally move to the same place in species but not in number. But Aristotle rejected this possibility on the ground that there would then be no reason why in our own universe different particles of earth would move to numerically different centers—which is contrary to the evidence of the senses. So there can be only one center to which all particles of earth, having the same form or nature, naturally move, and one circumference to which all particles of fire naturally move. In short, there can be only one world.⁴⁰

Aristotle also reasoned that there cannot be many worlds because the heavens of our own contain all the available material, with none left over for other worlds. Theoretically he saw no reason why the form or nature expressed by the term 'world' could not be realized in many particular worlds, as the form of circle can exist in many particular bronze or gold circles. But this possibility is ruled out by the fact that the one instance of world perceptible to us exhausts all the matter, leaving none for other worlds. The case would be the same if one man were created containing all flesh and bones; there would be none left for other men.⁴¹

In the first half of the thirteenth century there were Christian thinkers who did not find these arguments convincing. Better informed than Aristotle through revelation, they believed that God created the world from nothing and that his infinite creative power is not exhausted by the production of a single world. Writing about 1225 or 1230, Michael Scot reported: 'There are some who pretend that God, being omnipotent, had the power and is still able to create, over and above this world, another world, or several other worlds, or even an infinity of worlds, composing these worlds either of elements of the same species or nature as those that form this one, or from different elements'. Michael Scot himself did not share this view. While acknowledging that God is all-powerful, he was too good an Aristotelian to think that in fact there could be many worlds. 'God can do this', he wrote, 'but nature cannot bear it, as Aristotle says in De caelo et mundo, book 1, chapter 3. It follows from the very nature of the world, from its proximate and essential causes, that a plurality of worlds is impossible. Nevertheless, God could do this if he wanted to'.⁴² In other words, there is a distinction between the power of God taken absolutely and his power relative to the subject of his operation. He has the power, absolutely speaking, of doing many things that can never be realized because nature is not capable of receiving these actions of the divine power. This is the case with the creation of a plurality of worlds.

Michael Scot's ingenious method of harmonizing Aristotle and the Christian faith was followed by others in the thirteenth century. William of Auvergne never doubted the omnipotence of God and yet, like Aristotle, he could not conceive of a plurality of universes. He pointed out that the word 'universe' itself contains the notion of oneness: a universitas is 'a multitude gathered into a unity' (in unum versa multitudo). A 'universe' of colors is the union of all colors under one genus. Similarly, there is a universe of beings all united by their sharing in the nature of being. Outside this universe there can be nothing. The oneness of the universe is also proved by the oneness of its divine source.⁴³

In a similar vein, St. Thomas argued that the universe is one by its very nature. It has a unity which consists in the order of all its parts to each other and to its creator. Since the universe has one order, all creatures belong to one universe.₄₄ The appeal to the omnipotence of God did not shake St. Thomas' conviction of the oneness of the universe, for God did not create the universe with sheer power but with wisdom, and wisdom demands that everything have one order and be directed to one end. St. Thomas was also sympathetic to Aristotle's arguments that the present universe exhausts all the available material, and that the elements, no matter how widely dispersed, naturally tend to one natural place.⁴⁵ Of course, God could make the present universe better by creating many other species or by ameliorating all its parts. If the amelioration added to the universe's essential goodness, the result would be a different universe essentially and specifically better than ours; but in any case there would be but one universe.⁴⁶

To the Franciscan Richard of Middleton this conceded too much to Aristotelianism and failed to give proper weight to the divine omnipotence. God could have produced another universe besides the present one, and he still has the power to do so if he wished. Nothing prevents this on his part, for he can do everything that does not include a contradiction, and a plurality of worlds is not contradictory. No finite universe exhausts the infinite creative power of God. Neither does anything on the side of the universe stand in the way of a plurality. Matter does not, for it has been created out of nothing; it was not created from a preexistent stuff that would limit the scope of the divine action. Moreover, there is no receptacle, such as space, which receives the whole universe and makes it one. Neither do the special natures of the four elements prevent a plurality of worlds. God could create other worlds with elements of the same nature as ours. In these worlds earth would naturally move to the center and rest there, just as it does in our world. In the hypothesis of many worlds, each with its own center, earth would naturally tend to be at rest in whichever center it was first located, and it would not naturally tend to move to the center of another world.⁴⁷

Richard of Middleton felt he was on sure ground in adopting this position, for in 1277 Stephen Tempier, the Bishop of Paris (and also a master of theology, as Richard pointedly adds), condemned the proposition that God could not produce many worlds.⁴⁸ And this is not all that God can do. If God has infinite power, he could give the outermost sphere of the heavens, which according to the Aristotelians has only a circular movement, a lateral movement as well. He could also create a universe which, though not actually infinite or infinitely divided, could be expanded or divided beyond any given limit. Writing in an age in revolt against Greek necessitarianism, this Franciscan theologian was raising the possibility of viewing the universe differently from Aristotle and his commentators.⁴⁹

Ockham's speculation about the possibility of other worlds shows the same effort to free Christian thought from the shackles of Aristotelianism. Like Richard of Middleton, he does not consider Aristotle's arguments for the oneness of the world demonstrative. Elements of the same species need not move to numerically the same place; there can be several worlds, each with its own center and circumference, to which the elements would naturally tend if displaced from them. Ockham argues for this possibility not only a priori, like Richard of Middleton, but also from experience. If two fires are lighted in different places on the earth, say in Oxford and Paris, they naturally move upwards to the circumference of the heavens, but not to numerically the same place. Only if the fire at Oxford is placed in the same spot as the fire at Paris will it move to the same place as the fire at Paris. Similarly, if the earth of another world is placed in ours, it will by nature tend to the center of our world; but within the heavens of another world the earth will naturally tend to rest at its center. The reason why particles of earth in the two worlds will move to numerically different centers is not only that these particles are different in number, but also that they are in different situations in their respective heavens. The case is similar to the two fires that move to different places on the circumference of our universe because of their different situations in this universe.⁵⁰

It is true that the outermost sphere or circumference of our world is one continuous body and hence one in number; but it does not follow that two fires in different places on earth tend upwards to numerically the same place, for they move to numerically different parts of the circumference. With equal reason different particles of earth within the confines of distinct worlds could move to different centers.⁵¹

But if a particle of earth in another world naturally moves to the center of that world, would it not naturally move away from the center of our world? If it moved to the center of our world, its motion would be violent and not natural—which is clearly false, because in our experience earth moves naturally to the center of our world. Ockham grants that on the hypothesis of another world, earth moving towards its center would naturally move away from the center of our world, but he insists that this behavior of the earth would not be per se but per accidens, owing to the situation of the particle of earth within the boundary of its own world. If placed between the center and circumference of the world, fire naturally tends upwards to the circumference, but it moves away from the opposite side of the circumference. It recedes from the opposite side per accidens, owing to its situation in the world. If the same fire is located between the center and that part of the circumference, it would naturally move upwards to it. Thus not only the nature of the elements but also their situation in a world must be taken into account when explaining their motion. A particle of earth can naturally move downwards to the center of one world and per accidens, owing to its position in that world, move away from the center of another world.⁵²

Accordingly, the nature of the elements and their natural movements place no barrier to a plurality of worlds. Neither does the limited amount of matter available for their production. Granted that the present world exhausts all the matter God has created, it does not contain all he can create. An omnipotent God is not restricted to produce a certain amount of matter; he can always create more, both celestial and terrestrial, and form from it other worlds like, or better than, our own.⁵³

Can God create other worlds essentially better than ours without limit, or would he finally reach a best of all possible worlds? Ockham does not presume to settle this question but is content to remark that the answer depends on whether or not there is a limit to the degree of perfection God can give to individuals in other species. Those who say there is no limit would conclude that there is no best of possible worlds; those who affirm a limit would conclude the opposite. However this may be, there is no doubt that God can create a world essentially and accidentally more perfect that the present one.⁵⁴

III

Ockham's treatment of the possibility of a better world is a good illustration of his complex relationship to Aristotelianism. He has no quarrel with Aristotle as far as the actual constitution of the world is concerned. He does not suggest that the world is different from Aristotle's, or that in fact there are other worlds besides the one described by him. What interests Ockham is not so much the scientific question of the actual structure of the world as the theological issue of what worlds are possible, given the absolute power of God. Lacking the Christian faith, Aristotle did not believe in the divine freedom and omnipotence. He did not realize that the present world is governed by God's potentia ordinata, but that there are other and better worlds that come under his potentia absoluta.⁵⁵ Hence he took the limitations of the present world to be those of all possible worlds. He also failed to see that his arguments for the oneness of the world are not demonstrative but only probable, leaving open the possibility of other worlds better than our own.

The question remains why Ockham, unlike other Christian theologians, did not consider the Aristotelian arguments for the oneness of the world to be truly demonstrative. As we have seen, Michael Scot believed as firmly as Ockham that God has the power to create other worlds, but he denied the real possibility of plural worlds because 'nature cannot bear it'. A plurality of worlds is impossible, in his view, not because of any limitation on the side of God but because of the nature of the world.

This suggests that Ockham's conception of nature was not Aristotelian; and this is indeed the case. For Aristotle, each of the four elements has a form or nature, in virtue of which it naturally moves to its proper place when removed from it. Having the same nature, particular instances of each element must naturally have the same movement. As Aristotle says, 'the particular instances of each form must necessarily have for goal a place numerically one'.⁵⁶ From this he deduced the oneness of the world. Its oneness follows strictly from the oneness of the forms or natures with which the elements are endowed. For Ockham, on the contrary, bodies share no forms or natures. All particles of earth or fire have been created very similar to each other, and hence their movements are also very similar; but this is not because they have the same form or nature.⁵⁷ With the removal of natures or essences from individuals, the force of the Aristotelian argument for the oneness of the universe is lost. There is no longer a strict necessity for bodies to move to one place or that there be but one world. Ockham introduces the notion of the 'situation' (conditio) of the elements, thereby profoundly modifying the Aristotelian conception of their natural movement. Because they are differently situated in their respective worlds, heavy and light bodies move naturally up and down, but not to the same center or circumference. Even within the same world a light body, owing to its different situation, will natually move upwards to one place in the heavens and away from the opposite side of the heavens. We are here in the presence of a new, non-Aristotelian, conception of nature which is the philosophical basis of Ockham's doctrine of the possibility of a plurality of worlds. If more, and better, worlds are possible for him, it is because the Ockhamist nature, unlike the Aristotelian, can 'bear it'.

From a theological perspective Ockham's guiding principle was the freedom and omnipotence of God.⁵⁸ Above all else he wished to vindicate these attributes of the Christian God against the necessitarianism of the Greek and Arabian philosophers. Relying solely on natural reason they concluded that God is not a free but a necessary cause of the world, that his immediate causation does not extend to all its details, and that he is limited to producing the present world. Ockham did not think natural reason can effectively refute these philosophical tenets; it can at best offer persuasive arguments for the freedom of God as a creator. St. Thomas' method of establishing this divine freedom and his refutation of Greek necessitarianism had no appeal to Ockham; indeed it must be said that he showed little understanding of the Thomistic approach to this subject and he never adequately came to grips with it. Lacking a truly demonstrative proof of the divine freedom in relation to creatures, Ockham's Christian faith alone assured him that God can produce things he has not made and will not make, and that he can create many worlds and better ones than our own.

Of course all medieval theologians believed in the divine omnipotence. Every time they recited the Creed they professed their faith in 'one God, the Father almighty'. In this respect there was nothing to distinguish Ockham from the other theologians, such as Abelard, William of Auvergne, or St. Thomas Aquinas. The fact that the God of Ockham has the power to do things that the God of his predecessors could not do clearly indicates that he was giving a new interpretation to the divine omnipotence. A direct consequence of the divine omnipotence, as he saw it, was the divine freedom regarding the whole order of creation—a freedom that entailed the denial of any laws, ideas, or essences, that might rule the creative act. The God of Ockham is under no obligation to obey moral laws,⁵⁹ nor is he obliged to use eternal ideas or essences as a pattern of his creation.⁶⁰ He vigorously opposed any doctrine of the divine ideas that defined them as preconceived essences through which God created the world. To Ockham, this conceded too much to the necessitarianism of the philosophers, for it implies a limitation on the divine freedom and power, as though God's creative act were governed by eternal ideas or essences. In fact, Ockham insisted, God has no universal ideas as a pattern of his creation; he has ideas only of individuals, and these ideas are nothing but the individuals themselves producible by him. This ensures the absolute freedom of God as a creator as well as the complete contingency of his creation. It also guarantees that this is not the only possible world, but that other, and better, worlds are within the divine power. In the words of Lovejoy, 'The world contained whatever it had pleased its Maker to put into it; but what sort of creatures, or how many of them, this might mean, no man had any means of judging, except by experience or revelation'.⁶¹

Notes

¹ Arthur O. Lovejoy, The Great Chain of Being. A Study of the History of an Idea (New York, 1936), p. 52.

² ibid., pp. 144-182. For Leibniz' doctrine, see his Theodicy, 194, trans. E. M. Huggard (London, 1951), pp. 248-249; The Monadology, 53-60, trans. R. Latta (Oxford, 1898), pp. 247-250; The Principles of Nature and Grace, in T. V. Smith and M. Greene, From Descartes to Kant (Chicago, 1940), p. 364.

³ Lovejoy, ibid., p. 75.

⁴ ibid., p. 70.

⁵ ibid.

⁶ See A. C. Pegis' reply to Lovejoy in Saint Thomas and the Greeks (Milwaukee, 1939); also H. Veatch, 'A Note on the Metaphysical Grounds for Freedom, with Special Reference to Professor Lovejoy's Thesis in "The Great Chain of Being"', Philosophy and Phenomenological Research 7 (1947) 391-412, and A. Lovejoy's reply, pp. 413-438. A. C. Pegis, 'Principale Volitum: Some Notes on a Supposed Thomistic Contradiction', ibid., 9 (1948) 51-70; A. Lovejoy, 'Necessity and Self-Sufficiency in the Thomistic Theology: A Reply to President Pegis', ibid., 71-88, and A. C. Pegis' reply, ibid., 89-97; A. Lovejoy, 'Comment on Mr. Pegis's Rejoinder', ibid., 284-290, and A. C. Pegis' reply, ibid., 291-293.

⁷ 'Ainsi, Duns Scot enseigne simultanément qu'il ne peut y avoir d'arbitraire irrationnel dans les ceuvres de Dieu, mais que le choix (non l'essence) de chaque ordre rationnel dépend de sa volonté. C'est en ce sens qu'il faut entendre les déclarations relatives au bien et au mal, qui semblent les soumettre á l'arbitraire du vouloir divin' (E. Gilson, Jean Duns Scot (Paris, 1952), p. 611).

⁸ Peter Lombard, Sententiae in IV Libris Distinctae, 1. 1, d. 44, c. I (Grottaferrata, 1971), pp. 303-304. The Lombard refers to certain scrutatores who claimed that God cannot make something better than he has made it, for if he could and did not he would be envious and not supremely good (p. 304, lines 1-4). This is a reference to Abelard (p. 303, n.). See Abelard, Theologia Christiana, 5 (PL 178. 1326B-1327B); Theologia 'Scholarium' 3.5 (PL 178. 1093 D, 1094C). The reference to Augustine is from Abelard (ibid., 1054A), In libro quaestionum 8 3, 50 (PL 40. 31-32). St. Thomas also refers to this position of Abelard, whom he calls 'magister Petrus Almalareus' (Almarareus), in De potentia Dei, 1.5.

⁹ 'Circa istam quaestionem primo supponendum est quod Deus est causa effectiva rerum'; I Sent., 43.1B (Lyons, 1495).

¹⁰ 'Intentio ergo Philosophi est quod Deus ut (leg. est) causa immediata et totalis omnium substantiarum separatarum; sed generabilium et corruptibilium (secundum eum) non est causa immediata nec totalis nec partialis, sed tantummodo mediata'; 2 Sent., 6C.

¹¹ ibid., A.

¹² Scotus, Rep. Paris., 2.1.3, nn. 5-9; 22 (Paris, 1894), pp. 532-536. See E. Gilson, Jean Duns Scot, pp. 331-332. For Avicenna's doctrine of creation, see L. Gardet, La pensée religieuse d'Avicenne (Ibn Sina) (Paris, 1951), pp. 62-68.

¹³ '… sed Deo non convenit diffinitio causae efficientis, quia quinto Physicorum et alibi frequenter dicit Philosophus quod causa efficiens est unde principium motus…, Ockham, 2 Sent. 6B. See Aristotle, Metaphysics, 5.2. (1013a29); Physics, 2.3 (194b29-31).

¹⁴ Ockham, ibid., C.

¹⁵ Avicenna, Metaph., 6; 1 (Venice, 1508), fol. 91rb. See E. Gilson, 'Notes pour l'histoire de la cause efficiente', Archives d'histoire doctrinale et littéraire du moyen âge 37 (1962) 7-31; W. Dunphy, 'St. Albert and the Five Causes', ibid., 41 (1966) 7-21.

¹⁶ 'Ad ultimum dico quod intentio Aristotelis fuit quod primum ens sit causa finalis aliorum sed non efficiens, quia ponit quod corpora caelestia cum aliis causis inferioribus producunt omnia ista inferiora'; Ockham, Quodl., 4.2 (Strasbourg, 1491). For Averroes, the Intelligences exercise final and formal, but not properly efficient, causality on the sublunar world. See Averroes, In IV De Caelo, 1; 5 (Venice, 1574), fol. 234A.

¹⁷ Ockham, Quodl., 2.1. Neither can an adequate proof be given that God is the final cause of any effect. Quodl., 4.2. In his Commentary on the Sentences Ockham says that Aristotle proved by reason that God is the cause of all things, but not that he caused the world contingently or with a beginning in time. 2 Sent. 6B.

¹⁸ 1 Sent., 43, 1B-L.

¹⁹ St. Thomas, Summa theologiae, 1, 82, 2; 1, 41, 2 ad 3.

²⁰ Ockham, I Sent., 43. 1C.

²¹ ibid. Elsewhere St. Thomas gave this proof, but unfortunately Ockham does not seem to be aware of this; in any case he does not allude to it in the present context. The Thomistic proof rests upon the fact that only the divine goodness is the natural and principal object (principale volitum) of the divine will. As such, it alone is proportionate to the divine will and is willed necessarily. Similarly the human will necessarily wills its natural and proportionate end, which is happiness; but it wills particular goods freely. Since the good of creatures is not proportionate to the divine will, it does not necessitate that will but is willed freely and contingently. See St. Thomas, ST 1, 19, 3; De potentia, 1, 5; De Veritate, 23, 4; Contra gent., 1, 81. On God's freedom in creation, see A. C. Pegis, 'Necessity and Liberty: an Historical Note on St. Thomas Aquinas', The New Scholasticism 15 (1941) 18-45.

²² 'Dupliciter accipitur… producere aliquid contingenter. Uno modo quod simpliciter potest… producere et non producere. Et isto modo quidquid producit quemcumque effectum, producit contingenter, quia po-test Deus facere quod non producat. Alio modo accipitur pro illo quod producit aliquem effectum, et nullo variato ex parte sua nec ex parte cuiuscumque alterius habet in potestate sua ita non producere sicut producere, ita quod ex natura sua ad neutrum determinatur.' 1 Sent., 1, 6. 1 (St. Bonaventure, N.Y., 1967), p. 501, lines 2-11.

²³ 2 Sent. 6BC.

²⁴ 1 Sent. 43, IG. These arguments of Scotus are taken from his Opus Oxoniense (Ordinatio), 1, 8, pars 2, q. unica; 4 (Vatican City, 1956), pp. 310-315. See E. Gilson, Jean Duns Scot, pp. 270-278.

²⁵ Scotus, ibid., p. 313, note a.

²⁶ Ockham, ibid., H.

²⁷ ibid., K.

²⁸ ibid., L.

²⁹ 'Ideo quod Deus sit causa libera respectu omnium tenendum est tanquam creditum, quia non potest demonstrari per aliquam rationem ad quam non responderet unus infidelis; persuaderi tamen potest sic…', 2 Sent. 4-5, E. For Ockham's notion of demonstration, see D. Webering, Theory of Demonstration according to William Ockham (St. Bonaventure, N.Y., 1953).

³⁰ I Sent. 43, IN.

³¹ 'Sed in ista quaestione accipiendus est mundus praecise pro uno universo quasi composito ex partibus quae sunt substantiae, et non secundum quod includit accidentia cum substantia' (1 Sent. 44, lB. This description of the world fits in well with Ockham's doctrine of a collective whole. A world has the same kind of unity as a city, a nation, an army, a kingdom, the church, or a university. They are not one reality but an aggregate of individuals having only the unity of a collection (unitas collectionis). See Quodl., 7.13; In libros Physicorumn, Prol., ed. P. Boehner, Ockham, Philosophical Writings (London, 1957), p. 7.

³² 'Respondeo, vocando universum universitatem creaturarum infra unam superficiem contentarum, quae a nulla alia superficie continetur infra illam universitatem, comprehendendo etiam superficiem continentem.' Richard of Middleton, 1 Sent. 44, 4 (Brescia, 1591; rpt. Frankfurt, 1963), p. 392.

³³ William of Auvergne, De universo, primae partis principalis, pars 1, cap. 13; 1 (Paris, 1674), p. 607.

³⁴ Ockham, 1 Sent. 44, lB.

³⁵ ibid., C. See St. Augustine, De Genesi ad litteram, 11.7 (CSEL, 28/3. 340); Peter Lombard, Sententiae in IV libris distinctae, 1. 1, d. 44, c. 1; p. 304, lines 23-25.

³⁶ Ockham, ibid., D.

³⁷ ibid.

³⁸ ibid., E.

³⁹ ibid. See Aristotle, De caelo, 1. 8 (276al8-b22).

⁴⁰ Ockham, ibid. See Aristotle, ibid., 277al-13.

⁴¹ Aristotle, ibid., 277b26-278b9.

⁴² 'Et dicendum quod quidam dicunt quod Deus potuit et potest ita cum isto mundo alium et alios facere, vel etiam infinitos cum sit omnipotens, et hoc ex elementis eiusdem speciei et naturae, vel etiam diversae. Sed ista positio insufficiens est. Et causa huius est quia, quamvis Deus possit hoc facere, non tamen natura hoc posset pati, ut habetur primo Caeli et Mundi, tertio capitulo.

Quia quantum est de natura mundi impossibile est esse plures mundos, et hoc quantum ad eius causas proximas et essentiales, licet hoc Deus posset si vellet. Multa namque Deus de potentia sua apta posset facere quae respectu fieri non possunt. Cuius causa est quia non omnis potentia activa convertitur in passivam nisi solum quando patiens habet proportionatum et possibilitatem ad receptionem illius. Natura vero causata non est talis potentiae receptiva, quantum est de natura sui, scilicet quod sit receptiva plurium mundorum simul.' Michael Scot, Super auctore spherae (Venice, 1518), fol. 105b. See P. Duhem, Etudes sur Léonard de Vinci 2 (Paris, 1909), pp. 73-74. For the history of the problem of plural worlds, see ibid., pp. 57-96, 408-423.

⁴³ 'Universitas, sicut apparet etiam ex ipsa nominatione, non est nisi in unum versa multitudo; versa autem non intelligitur nisi collectione, vel adunatione in aliquid, vel sub aliquo, quod tota illa multitudo communicat; quemadmodum dicitur universitas colorum quae colligitur ad genus, et sub genere quod omnes colores communicant'. William of Auvergne, De universo, primae partis principalis, pars 1, cap. 11; 1 (Paris, 1674), p. 605 C.

⁴⁴ St. Thomas, ST 1, 47, 3.

⁴⁵ ibid., ad 3. See In I De caelo et mundo, 19, 14; 2 (Rome, 1886), pp. 78-79.

⁴⁶ St. Thomas, I Sent. 44.1.2; ed. Mandonnet, 1 (Paris, 1929), p. 1018. God has the power to create things he has not actually created, De potentia, 1.5; ST, 1.25.5. Any world God created would be the best in relation to his goodness and wisdom; in short, there is no best of all possible worlds, De potentia, ibid., ad 15.

⁴⁷ Richard of Middleton, ibid.

⁴⁸ Tempier condemned the proposition: 'Quod prima causa non posset plures mundos facere.' Chartularium universitatis Parisiensis; ed. Denifle and Chatelain, 1 (Paris, 1889), p. 543, a. 473.

⁴⁹ See E. Gilson, History of Christian Philosophy in the Middle Ages (New York, 1954), pp. 348-349.

⁵⁰ Ockham, I Sent., 44, IF.

⁵¹ ibid., G.

⁵² ibid., H.

⁵³ ibid., I.

⁵⁴ ibid. M.

⁵⁵ For the distinction between these two divine powers, see Quodl. 6. 1: 'Haec distinctio est sic intelligenda quod posse Deum aliquid quandoque accipitur secundum leges ordinatas et institutas a Deo et illa dicitur Deus posse facere de potentia ordinata. Aliter accipitur posse pro posse omne illud quod non includit contradictionem fieri, sive Deus ordinavit se hoc fac-turum sive non, quia multa potest Deus facere quae non vult facere.'

⁵⁶ Aristotle, De caelo, 1.8, 276b32.

⁵⁷ Nature, for Ockham, is an absolute, positive, extramental reality: 'Per naturam intelligo rem absolutam, positivam, natam esse extra animam (3 Sent., IC). It is also individual of itself and in no way common or universal. See I Sent., 2, 6-7; 2 (St. Bonaventure, N.Y., 1970), pp. 160-266.

⁵⁸ Fr. Léon Baudry gives a good defense of Ockhamism as a philosophy of the divine omnipotence. See his Le Tractatus de principiis theologiae attribué à G. D'Occam (Paris, 1936), pp. 37-42. More correctly, it should be called a 'theology of the divine omnipotence' since this divine attribute is solely a matter of faith. See also R. Guelluy, Philosophie et théologie chez Guillaume d'Ockham (Louvain-Paris, 1947).

⁵⁹ Ockham, 2 Sent. 5H; 4 Sent. 9EF. See G. Leff, William of Ockham (Manchester, 1975), p. 496: 'Absolutely then the criterion of good or bad is what God wills or rejects, which is ipso facto always for a good end … it is true that for Ockham what God decrees is ultimately the measure of all value'; F. Copleston, A History of Philosophy 3.1 (New York, 1963), p. 116: 'For Ockham, however, the divine will is the ultimate norm of morality: the moral law is founded on the free divine choice rather than ultimately on the divine essence.'

⁶⁰ Ockham, 1 Sent. 35, 4-5. L. Baudry (Le Tractatus de principiis theologiae attribué à G. D'Occam, p. 39, n. 2) points out the connection between Ockham's defense of the divine freedom and his doctrine of the divine ideas as purum nihil: 'C'est donc le souci de sauvegarder l'absolue liberté de Deu qui conduit Guillaume d'Occam à nier que les essences possedent l'être ab aeterno. Par où sl'on voit une fois de plus que l'idée de la toute-puissance anime toute la doctrine.'

⁶¹ Lovejoy, The Great Chain of Being, p. 70.