Selected essays presented at Aquinas and the Arabs / Thomas d’Aquin et ses sources arabes research seminars in North America (Fall) and Paris, France (Spring)



Work in progress


Aquinas on the Eternity of the World in II Sent., d 1, q 1 art. 5 and his Arabic/Islamic and Jewish Sources


                                                                                             Luis Xavier López-Farjeat

                                                                                  Universidad Panamericana, Mexico




Ancient Greek philosophers from Parmenides and Heraclitus to Aristotle, and the Stoics, shared the common view of the eternity of the world. It is well known that later philosophers, Jewish, Christian, and Muslim, thoroughly discussed this issue since the eternity of the world seems to be incompatible with the doctrine of creation in time. There are numerous discussions on this subject both in the philosophy of Hellenistic commentators and in medieval philosophers. In this paper I will revise the way in which Thomas Aquinas makes use of Arabic/Islamic philosophers, especially Avicenna and Averroes, and of Maimonides, the Jew, when he addresses this problem in II Sent., d 1, q. 1, art. 5. Aquinas tries to refute some Aristotelian arguments for the eternity of the world coming from the Physics and from the De Caelo. Most of the works devoted to discuss the proofs for the eternity of the world focus their analysis on the physical and metaphysical character of the problem. However, I think that it is also relevant to attend Aquinas’ argumentative strategies. Aquinas thinks that for Aristotle the question of the eternity of the world is a dialectical problem and this is why he concludes, following Maimonides, that there is not a demonstrative argument in this regard within the Aristotelian corpus. This assertion is not precise but in this paper I will allude this discussion.


It is true that the method by which Aristotle discusses the matter is clearly dialectical. In Topics I, 11, 104b 16 he mentions that the problem on the eternity of the world is a dialectical one.[1] Therefore, Aquinas interprets that there are not demonstrative proofs in this respect. However, there are strong reasons in order to conclude that both Aristotle and Averroes considered their arguments as correct and demonstrative. In his Commentary on the Sentences Aquinas tries to make clear that those arguments are dialectical and, in this sense, they are just probable. In order to discuss the implications of Aquinas’ understanding of the eternity of the world as a dialectical problem I will proceed in the following order: first, I will introduce a general view of the problem of the eternity of the world in the Arabic tradition including its Greek background; second, I will present Aquinas’ view in II Sent., d 1, q. 1, art. 5 paying attention to the references to Avicenna, Averroes and the way in which he introduces Maimonides in order to give a possible solution to the problem; third, I will finish with a short disquisition on the advantages of moving this problem from the demonstrative to the dialectical realm. Within my analysis I will show that Aquinas adopts some metaphysical aspects coming from Avicenna, some views from Averroes’ natural science, and the argumentative strategies of Maimonides.







Aristotle rejects the possibility of the world having a beginning. Hence, he formulates several arguments in order to prove the eternity of the heavens, of matter, and of time and motion. When testing his own position Aristotle discusses some arguments for creation having a beginning. This is a common dialectic strategy within the corpus. However, as I will argue later this does not mean, as Aquinas interprets, that the problem has exclusively a dialectical status. Aristotle is convinced that the world is eternal (just to mention some relevant passages: Metaphysics XII, 6, 1071b; Physics VIII, 1, 251a 1-251b 1-25) His position had a strong influence even in Neoplatonism but it was clearly modified. For instance, Plotinus followed Aristotle’s position but he states an ultimate principle for everything: the One. Plotinus conceived that the world takes its eternal existence from the One through a process of emanation (Enneads I, 6). Hence, the One produces everything through an eternal and voluntary process where matter itself is generated at the last part of the process. Matter is not generated ex nihilo but neither exists independently. Plotinus’ position is neither Aristotelian nor compatible with creation ex nihilo. His views were very influential among Arabic/Islamic theologians and philosophers. It is known that they learned Plotinus’ position as an Aristotelian one through the Theology of Pseudo-Aristotle, a relevant reference especially for al-Kindī (Adamson 2000: 105-125) and Avicenna (1951: 346-406).[2]


The Arabic/Islamic discussions on the eternity of the world shall be understood from both previous positions, the Aristotelian and the Neoplatonist. A third important influence is the Christian Alexandrian Neoplatonism of John Philophonus. His position is quite different from that of Plotinus since Philophonus refutes the Aristotelian arguments for the eternity of the world and he provides some allegedly demonstrative arguments for the temporal creation ex nihilo (Davidson 1987: 86-116). These arguments were helpful for some Islamic theologians and for the first philosopher al-Kindī who used them as proofs for the creation in time. But, at the same time, they were criticized by one of the most important philosophers, al-Fārābī (Mahdi 1967: 233-260). Philophonus wrote two treatises against the arguments for the eternity of the world, De Aeternitate Mundi contra Proclum (1984) and Contra Aristotelem (1987). In these two writings Philophonus argues against the two positions described above, i.e. the Neoplatonist and the Aristotelian. He scrutinizes the arguments for the eternity in order to remove any doubt that the world is created. According to Philoponus, Aristotle is not entirely consistent when he argues for the eternity of heavens, matter, time and motion. We do not know the complete version of Contra Aristotelem but fragments. However, in his Commentary on Physics, Simplicius (In Physics 1178, 7-35) reports one of the most influential arguments from Philoponus. The core of the argument is the impossibility of conceiving an infinite chain of beings: the existence of something needs the preexistence of something previous and Aristotle himself has argued that an infinite number cannot exist in actuality.[3] Hence, it seems that Aristotle is inconsistent. As I will show later, Aquinas himself will use this argument.


The argument above leads, according to some Islamic theologians, to a logical conclusion: if it is not possible to conceive an infinite chain of beings, it is necessary to conclude the existence of a first being. Nothing could be preexistent to this being and actually it is the Creator of the world in time. This proof of temporality (dalīl al-ḥudūth) can be found in one of the most representative theological groups, i.e. the Ash‘arites. There were several controversies on the way in which temporal creation should be understood. For example, the Ash‘arites disagreed with the Mu‘tazilites in regard to the understanding of nothingness (‘adam). While the Ash‘arites argued for the temporal creation from absolute nothingness,[4] the latter conceived a relative nothingness or, in other terms, the Mu‘tazilites did not find any problem in accepting the eternity of other objects than God (MacDonald 1965: 159-160). They discerned between nothingness as non-existence and nothingness as something that could be considered object of knowledge. Nothingness is something negative in the realm of the existence but is something positive in the realm of the essence. This is why the Mu‘tazilites believed that there was no conflict between a temporal creation and the eternity of the essences. 


As far as I can see, despite the controversies between the different theological schools, there are some general coincidences that allow us to propose a standard theory of creation among theologians. Most of them agree in the following points: a) God is eternal and He creates matter in time from nothingness; b) God creates everything by free choice; c) the nature of God is completely different from the nature of the world. Christian theologians, including Aquinas, shared this view. However, it was challenged, especially a) and b), by Islamic philosophers such as al-Fārābī, Avicenna and Averroes. I will concentrate my analysis in the last two philosophers since they were more influential than al-Fārābī in the philosophy of Thomas Aquinas.


Avicenna explains the origin of the world as an eternal (qadīm) emanation.[5] In different places but especially in al-Shifā’, al-Ilāhiyāt IX, he describes the emanative process as coming from the self-contemplation of God that originates the first intellect from which the multiplicity of the world proceeds. While God is a Necessary Being the others are just possible beings (al-Shifā’, al-Ilāhiyāt I, 6).


The Necessary Being is simple, perfect and immutable. He is one, single and unique (al-Shifā’, al-Ilāhiyāt I, 7). In God existence and essence coincide.[6] Actually, God cannot be otherwise but existent.[7] Necessity and possibility are modal categories of logic but Avicenna transfers these notions from the logical to the metaphysical realm. Both are related to a third notion or modal category, i.e. impossibility. Avicenna reasons as follows: a) there cannot exist an impossible being because our mind cannot conceive the impossible to be; b) the necessary being cannot be impossible; c) the possible being could or could not exist and if it exists, an external cause is needed (al-Shifā’, al-Ilāhiyāt I, 6; VIII, 3). This external cause is God: He is the one who gives existence to possible beings. Thus, possible beings are possible in se (mumkin al-wujūd bi dhātih)) and necessary ab alio. Every possible being has essence but not existence. The latter is given by an external cause and, therefore, existence is an accident for possible beings. These metaphysical assumptions are necessary in order to understand the emanative process. The Necessary Being cannot originate the impossible but the possible beings. When God gives existence to an essence He inserts a necessary existence in something that is possible in se. Given that it is not necessary for possible beings to exist unless an external cause gives them their existence, if the world (a possible being) exists, it is because God has generated it necessarily.  


The latter explanation suggests that Avicenna is rejecting God’s free choice. God thinks every possible essence and since He knows and wills the perfection of every being, then He adds the existence to the essence of the possible beings. God’s will is determined by its own perfection (al-Shifā’, al-Ilāhiyāt VIII, 4). This is one of the reasons why in his Tahāfut al-falāsifa (The Incoherence of the Philosophers) al-Ghazālī criticizes the Avicennan attempt to harmonize an eternal emanation with the creation of the world understood as a free choice of God. It seems that the emanative process occurs necessarily: through it self-contemplation the necessary being conceives a first intellect that generates the multiplicity of the possible beings. In this complex process, the most difficult part to understand is the way in which the necessary being is related to the possible being. Avicenna combines necessity and possibility.[8] The first intellect “emanates” from the necessary being. The next part of the process consists in the origin of the possible beings through an eternal emanation from the first intellect’s contemplation of God and itself. The emanative process has a triadic structure (intellect, soul, body): from the contemplation of the first intellect as described above emanates a second intellect and the soul and body of the ten heavenly spheres (al-Shifā’, al-Ilāhiyāt IX, 3). At the last link of the process there is the active intellect from which the sublunary world emanates. Hence, God produces (muḥdath) the world through several mediations.


Although according to this emanative process there is a strong relationship between God and the world, the distinction between the Necessary and the possible being helps to avoid any pantheistic implication. Actually, Aquinas will adopt this distinction. The world is concomitant to God’s essence but it does not share the same essence as God (al-Shifā’, al-Ilāhiyāt IX, 1). However, although Avicenna distinguishes between both beings, he assumes that a) God’s production of the world is voluntary and necessary, b) being the cause (God) eternal and being emanation his action (his effect) the emanative process is eternal; c) through the emanative process God gives the existence to possible beings and, in this sense, it is possible to assume a notion of creation (ibdā‘) (al-Shifā’, al-Ilāhiyāt I, 6).[9] This latter aspect is problematic: although an emanative process only makes sense if the world is eternal, Avicenna thinks that the term ibdā‘ also makes sense if we understand its metaphysical sense. To talk about “creation” does not imply that at some point in the process the world, the possible being, did not exist. It is not possible to think that the world has a beginning because God’s eternal action does not have a beginning (al-Shifā’, al-Ilāhiyāt I, 6). Hence, what Avicenna thinks is that in itself the possible being is non-existent because it has always depended on God’s action. The possible being is concomitant to God. If every possible being receives its existence from God —and this is what Avicenna calls ibdā‘— we can understand creation as an eternal process of producing the existence. Since the process is eternal Avicenna conceives a non-temporal creation, an eternal process in which God permanently produces the possible being making of it a necessary being by another.


The reactions after Avicenna’s position were critical. In his Tahāfut al-falāsifa  (The Incoherence of the Philosophers) al-Ghazālī affirms that philosophers have built arguments for the eternity of the world incompatible with the temporal creation of it as, according to the theological tradition, the Qur’an has stated. I will not analyze in depth al-Ghazālī’s arguments against the eternity of the world. What I want to highlight is the dialectical methodology that as every theologian, al-Ghazālī is using. At the end of the first discussion of The Incoherence, he argues that it is not possible to accept that philosophers have proven the eternity of the world and that the aim of his treatise is, precisely, to refute their arguments but not to support a particular point of view.[10]  


In addition to the physical and metaphysical mistakes that philosophers have made, al-Ghazālī transfers this problematic to a dialectical discussion. He shows the inconsistencies of the philosophical arguments formulating refutations but not demonstrations for his own position, i.e. the temporal origin of the world. This will be the same strategy that Maimonides will use: showing that the arguments for the eternity of the world are defective and they state just the possibility of the world being eternal is, in some way, an attempt to confirm that temporal creation is a possibility too.


Averroes continues with the dialectical discussion in his Incoherence of the Incoherence (Tahāfut al-Tahāfut). As it is well known, in this treatise he answers to al-Ghazālī but he also corrects the way in which al-Fārābī and Avicenna have understood some philosophical problems. Averroes argues for the eternity of the world in different places: in the Tahāfut al-Tahāfut, in his Decisive Treatise (Faṣl al-Maqāl) but especially in his commentaries on Metaphysics, Physics and on De Caelo. In the first treatise I have mentioned, i.e. the Tahāfut Averroes shows that neither al-Ghazālī nor al-Fārābī and Avicenna have reached demonstrative arguments for the creation in time and the eternity of the world, respectively. I will not analyze in depth each response that Averroes formulates in order to refute al-Ghazālī’s arguments. I just want to underline the dialectical character of the discussion and the way in which Averroes refines some philosophical concepts in order to state the debate in the correct terms. Averroes thinks that al-Ghazālī and the theologians have not understood, for instance, that God’s free will is determined by the most perfect alternative or, for example, they have a wrong conception of (1987: 22) God as agent (1987: 148-9). In each response, Averroes defends the eternity of the world and he argues that God produces it continuously. However, although he suggests that the arguments for the eternity of the world are more consistent, his main interest in this treatise is, in my view, to set the debate in the correct terms and to show that the controversy between philosophy and theology is just an apparent one. Hence, the aim of the Tahāfut is not to formulate the strong and demonstrative arguments for the eternity. However, in this treatise there are some traces of Averroes’ final position:


a)    The arguments that have been formulated by al-Ghazālī, al-Fārābī and Avicenna are not demonstrative. This is why it is necessary to reformulate their arguments. But, the first step is to show their inconsistencies and then, refine some philosophical terms as, for instance, “eternal”;

b)         Averroes distinguishes between two different senses of eternal: eternal in the sense of a continuous process of origination that has neither beginning nor end, and eternal as something self-sufficient and with no first cause. The world is eternal just in the first sense (1987: 162);

c)          If the world is not eternal by itself, then it needs an external agent. Hence, God is the first cause of the world. But that does not mean that he creates the world from nothingness. It means that God continuously produces it and, since God’s action is eternal, its effect has to be eternal, i.e. it has no beginning nor end.


In the Faṣl Averroes mentions once again the controversy between philosophers and theologians in the way in which both have understood the term “eternal” (qadīm) (1976: 55-6). Averroes assumes that there is a disagreement between both parties because theologians have understood the term qadīm as contradictory with the term muḥdath (translated as “produced in time”). Averroes finds that both theologians and philosophers agree in the necessity of interpreting the apparent meaning of the Qur’an. The Book mentions that the world was produced and both parties agree with that. However, theologians interpret as temporal production from absolute nothingness (‘adam) and the Book does not support an interpretation in those terms. There is no contradiction between philosophy and religion, but between philosophers and some theological interpreters. However, if theologians refine their terminology they will find that it is possible to harmonize both views.


Now, in addition to what Averroes states in both treatises the Tahāfut and the Faṣl, it is essential to complement his views with his commentaries on the Aristotelian corpus. In these commentaries, especially on Metaphysics, Generation and Corruption, Physics and on De Caelo, Averroes formulates some demonstrative arguments. In II Sent., d 1, q. 1, art. 5, Aquinas refers to some of the them. I will focus on those arguments that, as far as I can see, share something in common: they are Aristotelian. This precision is relevant because Averroes formulates some un-Aristotelian arguments in which it is possible to recognize the influence he received from Neoplatonism.


In the fourteen objections that Aquinas discusses in II Sent., d 1, q. 1, art. 5, Averroes’ commentaries on De Caelo and on Metaphysics are mentioned once each, while the commentary on Physics appears six times. Averroes wrote an epitome (jawāmi‘), a middle commentary (talkhīṣ), and a long commentary (tafsīr) on the Physics. The epitome is the only one preserved in Arabic. The middle and the long commentaries are preserved in Hebrew and Latin. The Latin translation from the long commentary is attributed to Michael Scotus and it was well known during the thirteen century. As Ruth Glasner (2009: 41-56) has observed, the long commentary was subject of massive revisions that reveal a strong influence by the Greek commentators, especially in the way in which Averroes analyzes the logical structure of Aristotle’s arguments. Averroes makes use of Theophrastus, Themistius, Alexander, and also Philoponus in order to reformulate and strengthen Aristotle’s arguments. In addition, in his reformulation of the arguments it is clear that Averroes is using the logical strategies of the Stoics and not those of Aristotle. This is quite relevant: Averroes is not interested just in formalizing Aristotle’s arguments but in emphasizing its demonstrative character.


In Physics VIII there are several arguments in order to demonstrate that motion, time, and the agent of motion are continuous and infinite. This book deals, as it is well known, with three central issues: a) the eternity of motion; b) the unmoved mover; c) the characteristics of the unmoved mover. Aquinas’ references in In II Sent., d 1, q. 1, art. 5 are coming from the first chapter of Averroes’ commentary, where the main arguments for the eternity are presented. A fundamental argument is the so-called “succession argument”: before any motion there must have been a previous motion or change, or a mover (In Physics VIII, 1).[11] Following Aristotle, Averroes explains that if there was a beginning of time, we should assume that the mover was still and at some point it started to move before any other mover. However, if this happens, it is necessary to postulate an earlier motion that caused the movement of the mover. Therefore, it is not possible to conceive a previous temporary move, but an eternal motion previous in nature. Averroes disagrees with Islamic theologians that, following John Philoponus, have understood that it is impossible to consider an infinite chain of motion and, therefore, it is necessary to establish a first motion in time. In contrast, Averroes, as Aquinas points out, argues for a continuous motion.


Aquinas does not accept the demonstrative character of Averroes’ arguments, but he will adopt some of his views on natural science. Although Aquinas defends the temporal creation of the world, he does not discard Averroes’ position and he considers it as a possibility. With some nuances, Averroes’ position will serve Aquinas to argue later on for the necessity of God’s action being eternal.  






In II Sent., d 1, q. 1, art. 5 Aquinas discusses the possibility of the world being eternal. In the fourteen objections Aquinas states several arguments for the eternity of the world, all of them coming from Aristotle and his Arab commentators. The arguments are divided in four parts: those that are built from i) the substance of the heavens, ii) time, iii) motion, and iv) the agent of motion. [Videtur quod mundus sit aeternus: et ad hoc possunt adduci rationes sumptae ex quatuor, scilicet ex substantia caeli, ex tempore, ex motu, et ex agente vel moverte]



[i) The substance of heavens]


(1)  According to Aquinas, in Physics 1 Aristotle builds the following argument: a) all that is ungenerable and incorruptible has always existed and will always exist; b) prime matter is ungenerable and incorruptible because all that is generated is generated in a subject, and all that is corruptible is an alteration of a subject, and prime matter is not a subject; c) hence, prime matter has always existed and will always exist. Now, given that matter is never deprived from its form, then matter has always been perfect in its forms from which the species are constituted. In conclusion, the universe from which these species are part has always existed.[12]


(2)  In De Caelo 1 Aristotle affirms that a) all that has no contrary is neither corruptible nor generable, because generation comes from the contrary and corruption results in the contrary; b) now, the heaven does not have contrary because nothing opposes to its motion; c) hence, the heaven is neither generable nor corruptible and it has always existed and will always exist.[13]


(3)  According to Aquinas, from the standpoint of faith the substance of the world is incorruptible. Now, following Aristotle in De Caelo 1 a) all that is incorruptible is ungenerable; b) therefore, the world is ungenerable; c) then, it has always existed. In order to prove the middle term, Aquinas affirms that all that is incorruptible has the potency to always exist. And, referring to all that has the potency to always exist, it is not as if sometimes it is and sometimes it is not. From the latter would follow that at the same time it would and would not be a being. Because something is always a being, from which its virtuality of being is determined. Therefore, if it always has the virtuality of being, it will always exist, because if it is supposed that at some time it does not exist, it would follow that it would exist and not exist at the same time. Then, no incorruptible is sometimes a being and sometimes not.[14]


(4)  The following argument appears in Physics 8 and in Averroes’ commentary on De caelo: a) if the world has been created from nothingness, then before the world there was vacuum; b) now, as Aristotle has shown and as our senses make evident, nature does not tolerate the vacuum; c) hence, it is impossible to conceive that the world has a beginning.[15]


[ii) Time]


(5)  The eternity of the world could be demonstrated from time: a) all that is always in its beginning and in its end, has always been and will always be; b) because something exists after the beginning and before the end; c) thus, time will always be in the beginning and in the end because time is nothing else but now; “now” is defined as itself being the end of the past and the beginning of the future. According to Physics 8 it seems that time has always existed and will always exist, just as motion, the mobile, and the whole world.[16]


(6)   a) All that cannot be shown as being still, but rather as always flowing, has before itself something from which it flows. b) But the “now”, as happens with the point, cannot be shown as still, but rather as ever flowing, because the whole character of time consists in flowing and succession. c) Therefore, before the “now” another “now” has to be set; hence, it is impossible to imagine that time had a first now. In conclusion and as Averroes has argued in his commentary on Physics 8, time has always existed.[17]     


(7)  The creator of the world precedes the world either only in nature or also in duration. If preceded only in nature, as the cause precedes the effect, then as the Creator existed also the creature existed. Hence, the world is eternal. But if it is preceded in duration, then the “before” and the “after” in the duration is the cause of the reason of time. Thus, before the whole world there was time; but this is impossible, because time is an accident of motion and it cannot exist without motion. In conclusion and according to Avicenna in Metaphysics 9, it is impossible that the world had not always existed.[18]  


[iii) Motion]


(8)  It is also possible to demonstrate the eternity of the world from motion. It is impossible for a new relation between two things to exist if there is no change in one of them, as happens in quality; two things are not made equal for the first time without augmenting or diminishing one of them. Now, every motion includes a relationship between the one that moves and the mobile, which are relationally oppose. Hence, it is impossible that there is a new motion if it is not preceded by some change either in the one that is moving or in the mobile, such as one approaching the other or something similar. In conclusion, as it appears in Physics 8 there is motion before any movement; and in this way motion is eternal and also the mobile and the world.[19]


(9)  All that sometimes moves and sometimes remains still, reduces to a continuous motion which always exists. The reason of this succession is that something that behaves in the same manner cannot be the cause of the alternation between motion and stillness; because what behaves always in the same manner always does the same. Hence, it is necessary that the cause of this alternation to be some motion that does not always exist, and thus a previous motion is necessary; now, since it is impossible to proceed ad infinitum it is necessary to come to a motion that always exists; and from here the previous conclusion. And this is Averroes’ reason in his commentary on Physics 8 and Aristotle’s as well. Averroes also introduces this reason in his commentary on Metaphysics 7 in order to demonstrate that if the world had been made, it would be necessary that this world were a part of another world and its motion could introduce the variation in the present world, either in the alternation between motion and stillness, or in the alternation between being a not being.[20]


(10) The generation of one thing is the corruption of another. Now, nothing corrupts if it is not previously generated. Hence, before any generation, there is generation and, before any corruption, there is corruption. Nothing of this could occur if the world did not exist. In conclusion, according to Aristotle in De Generatione 1, the world has always been.[21]



[iv) The agent of motion]


(11)        The same can be demonstrated from the standpoint of the agent of motion. It is necessary that any action or motion that comes from an agent or from something that moves does exist without it being moved. But the first agent or the first one that moves is c∫ompletely immobile. Thus, it is necessary that its action and motion always exist. The first premise is proved as follows: everything that moves or acts after it did not act nor move is brought from potency to act, because each one of those that act, does so according to that which is in act; therefore, if it acts after the non-activity, it is necessary for what was in potency now to be in act. Now, everything that is brought from potency to act does move; hence, everything that acts after the non-activity is moved (Physics 8).[22]


(12)        Either God is a voluntary agent or He is so because of necessity of nature. If He is so by nature’s necessity, since such reality is determined to one single thing, it is necessary that he does always the same; therefore, if the world has been made by Him, it is necessary for the world to be eternal. But if He is a voluntary agent, no will begins to work for the first time if a motion does not occur in the one who wills: either coming from something that it impeded existing before and stopping later; or stimulated now and not before by something that induces to act and that did not induce before. Hence, God’s will (which does not move) always being the same, it seems that He does not begin to act for the first time. This reason appears in Aristotle’s Physics 8, and in Avicenna’s Metaphysics 9, and in Averroes.[23]


(13)        For anyone who wants sometimes to act and sometimes not to act, it is necessary to imagine one time after another, distinguishing the time in which he wants to act from that in which he does not want to act. Now, imagining one time after another follows some change: either from imagination itself or at least from what is imagined, because the succession of time is caused by the succession of motion, as the philosopher states in Physics 4. As Averroes concludes in Physics 8, it is impossible for the will to begin any new motion if this is not preceded by another movement[24].


(14)        Any will to bring about an effect produces the effect immediately, unless what is willed lacks something that will be added later. For instance, now I have the will to make fire tomorrow when it is cold; what is wanted lacks the presence of cold but, when it comes, I will immediately make the fire, if I can, unless this lacks any other thing. Now, God had the eternal will to make the world because otherwise He would be mutable. Hence, it is impossible that He should have made the world from eternity, unless the world lacked something that was added to it later. This could not be added but through some action; therefore, it is necessary that in what was made for the first time, some action that makes the change should precede, and this, in such a way that nothing new ever proceeds from the eternal will, if it is not by an eternal motion. In conclusion, as Averroes states in In Physics 8, it is necessary that the world always existed[25].           


After these fourteen objections Aquinas states nine contrary arguments that, in my view, could be divided as follows: a) arguments based on the ‘necessity’ of the world and the heavens being created (1-2)[26], b) arguments based on the impossibility of the infinite (3, 4, 5, 6)[27]; c) arguments based on the distinction between God and the world (7, 8, 9)[28]. The first two arguments presuppose the necessity of the world and the heavens being created because they cannot exist by themselves. According to the first argument God is the cause of motion but He also creates the substance of the world. According to the second argument, if the heaven is created, therefore it has not always existed. These arguments are dialectical. They do not demonstrate the necessity of creation in time but they suggest that the arguments for its eternity are not conclusive. In both cases a premise is presupposed: nothing can exist by itself; thus, the world and the heavens received their beings from another. As it is clear, the arguments for the eternity claim that since motion and time are continuous, the matter of the world and the heavens is eternal. 


The arguments based on the impossibility of infinity recall those of John Philoponus. Aquinas resorts to Aristotelian arguments in order to show that the infinity cannot exist in actuality. He refers to Metaphysics II[29] and Physics III.[30] This is an alleged inconsistency. A possible solution consists in considering different kinds of infinity. As Aquinas points out following Aristotle, it is not possible to conceive infinite series of causes. However, as Aristotle himself —and Averroes following him— explains in Physics III, 6, 206a29-33, “infinity” can be understood from the point of view of a process. Hence, if the infinity is a process, it is referred to something that is not complete. In other terms, infinity cannot be in actuality but potentially. And this is precisely what Aristotle affirms in Physics III, 6, 206a14-29. Aristotle, Averroes, and Aquinas himself agree that infinity cannot exist in actuality. The arguments based on the impossibility of infinity are helpful against someone who conceives the infinity in actuality. However, what Aristotle and Averroes defend is a potential infinite.


Finally, we get to the arguments based on the distinction between God and the world. The three arguments consider the impossibility of the world and the heavens as eternal. But if this assumption is true, there would be no difference between God and the world. Nevertheless, those who argue for the eternity think that God being eternal and the cause of the world, the world (the effect) has to be eternal. If we accept the difference between God and the world, another problem arises: we would have to answer how can the eternal cause a finite effect. This last group of arguments against the eternity of the world shows the dialectic character of the discussion. They do not prove that the world is created; instead, they only provide another possibility. The supporters of the eternity reason as follows: if the cause is eternal, the effect has to be eternal. Their opponents think that if the cause and the effect are both eternal, there would be no difference between them. However, they would have to explain how could the eternal cause an effect substantially different.


Aquinas confirms the dialectic character of this discussion in his solutions. He considers three positions:


a)    That of the philosophers who argued that God and the world are both eternal (from Empedocles and Democritus to Plato and Aristotle). Aquinas explains the different approaches of the Greek philosophers and he concludes that Aristotle and his followers have given the most probable opinion. However, he concludes, all these opinions are false and heretical ([3498] Super Sent., lib. 2 d. 1 q. 1 a. 5 co. Alii dixerunt, quia res fuerunt ab aeterno secundum illum ordinem quo modo sunt; et ista est opinio Aristotelis, et omnium philosophorum sequentium ipsum; et haec opinio inter praedictas probabilior est: tamen omnes sunt falsae et haereticae)


b)    That of those who affirm that the world is created and, therefore, the world came into existence after God created it. They affirm that the fact that the world has a beginning is not only sustained by faith but also by rational demonstration ([3498] Super Sent., lib. 2 d. 1 q. 1 a. 5 co. volunt etiam quod mundum incepisse, non solum fide teneatur, sed etiam demonstratione probetur)


c)    That of those who affirm that everything except God has come into existence. However, they have to face the proposition God could have produced everything from the eternity. The problem is that it is not possible to prove that the world began to exist and this is something that has to be believed by divine revelation. Aquinas supports this alternative. It is impossible to build a demonstrative argument for the beginning of the world, nor one for its eternity ([3498] Super Sent., lib. 2 d. 1 q. 1 a. 5 co. Tertia positio est dicentium, quod omne quod est praeter Deum, incepit esse; sed tamen Deus potuit res ab aeterno produxisse; ita quod mundum incepisse non potuit demonstrari, sed per revelationem divinam esse habitum et creditum. Et haec positio innititur auctoritati Gregorii, qui dicit quod quaedam prophetia est de praeterito, sicut Moyses prophetizavit cum dixit Genes. 1: in principio creavit Deus caelum et terram. Et huic positioni consentio: quia non credo, quod a nobis possit sumi ratio demonstrativa ad hoc; sicut nec ad Trinitatem, quamvis Trinitatem non esse sit impossibile; et hoc ostendit debilitas rationum quae ad hoc inducuntur pro demonstrationibus, quae omnes a philosophis tenentibus aeternitatem mundi positae sunt et solutae: et ideo potius in derisionem quam in confirmationem fidei vertuntur si quis talibus rationibus innixus contra philosophos novitatem mundi probare intenderet)


Aquinas’ support of the third solution is quite relevant. As I have mentioned he is using dialectical arguments. And what he is going to show in his replies to the arguments for the eternity is that they are not demonstrative but probable: God could have produced the world from the eternity. The arguments for the creation in time are also probable per se but true by faith. Both positions the eternity and the temporal creation could be possible. Now, as Aquinas himself mentions, he uses the same argumentative strategy as Maimonides. It is quite representative that the assumption of God producing everything from the eternity is not false but a possibility. Put it in other terms, Averroes’ position is a possibility. Aquinas will refute the demonstrative character of the arguments for the eternity of the world. What he does in his responses to the arguments is to show that they do not have demonstrative status but are purely dialectical. That gives him the opportunity to formulate a group of arguments in order to affirm the possibility of the world being created. Neither the temporal creation nor the eternity of the world can be demonstrated. Both parties have valid arguments but they conclude with a mere possibility. Aquinas believes in temporal creation because it comes from divine revelation. The following passage is quite relevant since it underlines what I have explained, and it also provides Maimonides’ solution to this problem: 


Therefore, I say that neither of these questions has a demonstration, but at the most, probable or sophistic reasons for both of them. And this is what the words of the philosopher mean, who states that there are certain problems about which we have no reasons, such as the world being eternal [Topics I, 11]. Therefore, Aristotle himself never tries to demonstrate it, and this is evident from his way of proceeding, because every time he treats this question, he always adds some persuasive argument that he takes from the common opinion or from some sort of prove, that in no way belongs to demonstration. The cause why this statement cannot be demonstrated, is that the nature of the thing changes in the subject, depending of the subject being in its perfect state, and depending on it being in its first coming to be, as it comes from the cause; as the nature of the man that is already born is different from that which is still in its mother’s womb. Therefore, if someone wanted to argue from the conditions of a born and perfect man about the conditions of another which is imperfect and is still in its mother’s womb, he would mislead himself; as Rabbi Moses narrates about certain boy whose mother died a couple of months after being born and that, having grown in a solitary island, when he came to the age of discretion, he asked someone if men had been made and how. When explaining him the process of human birth, the boy objected that this was impossible, affirming that men could not live even one single day without breathing, eating, and disposing of its wastes and that, therefore, it could not live for nine months in its mother’s womb. In the same way are mistaken all those who want to show the necessity or impossibility of the beginning of the world recurring to the way things are done in an already perfect world: because that which now begins to exist, begins by motion; thus, it is convenient that motion precedes in duration, and it is also convenient that it precedes by nature, and contrary aspects are present. Now, all this is not necessary in the coming to be of any being since it comes from God.[31]   


Maimonides’ influence on Aquinas is quite important. According to Maimonides in the Guide of the Perplexed the main problem of the arguments for the eternity of the world is that they start from the consideration of the world as it is now to the explanation of the world as it might have been.[32] Thus, there is no way to find out whether the world had or had not a beginning. Since there is not a demonstrative answer in this respect, the problem has to be seen in the realm of dialectic and in this sense Maimonides’ proposal is to verify the logical arguments that the supporters of the eternity have stated. He concludes that Aristotle does not “demonstrate” the eternity of the world, but the temporal creation has not been demonstrated either. Thus, the problem appears clearly as a dialectic discussion. Maimonides does not want to demonstrate creation nor absolutely rejects the eternity hypothesis. He just shows that the arguments coming from both sides are weak. Since it is not possible to demonstrate either the creation or the eternity of the world, the discussion shall be moved from the realm of scientific demonstration to the realm of dialectic.







Aquinas is consistent in his adoption of Maimonides’ strategy. His replies to the arguments for the eternity do not demonstrate that the world has been created but they assert that there are not defintive proofs in order to discard temporal creation. Aquinas’ replies presuppose that creation is true because that is what divine revelation has stated. By formulating arguments that can be followed if one assumes divine revelation, Aquinas seeks to neutralize the alleged demonstrative arguments from his adversaries.


The responses to arguments 1, 2 and 3 state that matter and the heavens exist because God created them voluntarily in time.[33] However, these arguments depend on proving creation. The response to argument 4 seems to be more consistent. The argument holds that the world is eternal because otherwise we would have to conceive that before it there was vacuum; nature does not tolerate the vacuum; hence it is eternal. Aquinas focuses his response on the impossibility of vacuum understood as privation since any privation requires something to be deprived of. It is equivocal, according to Aquinas, to think on vacuum as certain entity that occupies a space. Rather, vacuum is a privation of a given reality that does occupy a space of its own. In this sense, the impossibility of the vacuum does not leads us to affirm the necessity of the eternity.[34]


Responses 5 and 6 reject the possibility of time being eternal.[35] Since the now is always flowing and it never stays still, it is impossible to determine a beginning and an end. For Aquinas it maes no sense to think of time as a succession of “nows”. He considers that it would be more consistent to postulate a beginning and an end. However, Averroes’ argument in his commentary on Physics VIII points out the difficulty of imagining that time had a first now. Both arguments the one that postulates a beginning and the one that denies it, have the same inconvenience: they are limited by the impossibility of defining the very first now.


The response to argument 7 accepts that God precedes the world in nature and in duration.[36] However, God’s duration is different from that of time. In other terms, God as eternal is not subject of time but its creator. This does not imply a radical difference between time and eternity. Instead, it points out the dependence of time from eternity. Response 8 answers to the eternity of movement distinguishing the kind of relationship between the mover and the mobile.[37] The argument for the eternity establishes the identity of the mover and the mobile. Aquinas’ response distinguishes different kinds of relationship in order to defend that in the act of creation the mobile receives the motion as something new coming from the mover.


In argument 9 it is stated that all that sometimes moves and sometimes remains still, reduces to a continuous movement that always exists. However, Aquinas answers that there is a difference between the eternal motion and the eternal will of God: the fact that God has an eternal will does not imply that the world has always existed. Aquinas emphasizes that God is a free agent who created the world according to his will but he is not determined by his creation.[38] The response to argument 10 avoids an infinite process of generation and corruption, which Aquinas substitutes for creation ex nihilo.[39] 


Arguments 11, 12, 13, and 14 are focused on the characteristics of the agent of motion.[40] The arguments for the eternity of the world affirm the necessity of an eternal agent since its effect seems to be eternal. In contrast, Aquinas’ answers arguing the convenience of God being a free agent. In response 11 Aquinas makes a distinction between two classes of agents: a) those which act determined by their nature and b) voluntary agents. The latter can be divided in those agents that act through an action that is not their essence; and those whose will is its action i.e. God. Since God’s will is eternal, his action is eternal. However, Aquinas affirms that this does not mean that He is determined to act in a definite way. Rather, his will acts freely. In God it is possible to harmonize free will and eternal action.  In response 12 Aquinas argues that God’s will does not move by an external finality. Being the world something external and inferior, God’s will is not  determined by the world: God’s will is self-determined. In responses 13 and 14 Aquinas rejects the propositions that state that God’s will is eternal and, therefore, the world is eternal. Particularly strong is the response 14: God introduces a finality in the world. If the world has always existed it is impossible to attribute it finality. According to Aquinas, the finality of the world is proportional to the divine will.


With this set of arguments, Aquinas neutralizes the creation in time/eternity of the world debate. This is an advantage for those following the divine revelation because he has shown that neither the arguments for the eternity nor the arguments for the creation in time offer certitude. The way in which Aquinas approaches this particular problem offers, in my view, helpful methodological guidelines for those cases where a philosophical proposition is in conflict with faith: a) Aquinas scrutinizes the arguments for the eternity and he concludes that they are not demonstrative arguments; b) therefore, the problem is moved to the realm of probability and, in this sense, it is more complicated to conclude that the arguments for the eternity are stronger than the arguments for creation; c) Aquinas shows that although it is impossible to demonstrate the temporal creation ex nihilo, it is possible to build rational arguments that state its possibility.


Aquinas ends the Distinction with some remarks on the arguments (in this case, nine arguments) against the eternity of the world. This time Avicenna and Averroes play on his side. And this is not strange. Aquinas was able to realize that although he did not share some views of the Arabs, their way of reasoning the philosophical problems, most of their premises, and many of their conclusions were useful in his defense of Christianity. I will just mention some of his remarks to arguments 1, 2, 5, and 8, where he explicitly refers to Avicenna and Averroes and points out the correct parts of their arguments. He affirms that the arguments he is going to refine are not demonstrative but it is necessary to give them an adequate response. What Aquinas does, in my view, is to concede that some arguments for the eternity consider some physical and metaphysical assumptions that are correct. I will start with Avicenna and afterwards with Averroes.  


In his remarks to argument 2, Aquinas affirms that Avicenna was correct when he distinguished between the creation previous in duration and the creation previous in nature (al-Shifā’, al-Ilāhiyāt VI, 1; IX, 4). According to Aquinas, Avicenna’s notion of “creation previous in nature” is true. It is correct to distinguish between the Necessary Being and the possible being. Avicenna understood creation as God being previous in nature because every possible creature receives its being by an external agent.[41]


When revising argument 1, Aquinas mentions Averroes’ De substantia orbis. He affirms that Averroes’ interpretation of Aristotle is the correct one when he states that God is the cause of motion of the heavens and He is also cause of its substance. It seems that both Averroes and Aquinas are assuming that Aristotle argued for God as an efficient cause. Evidently this will be disputed. However, Aquinas follows Averroes and explains that since God is eternal, the world and the heavens are eternal, but not in duration but because of God’s eternal influence.[42] Aquinas accepts that this argument is formally correct. In argument 5 Aquinas refers to Averroes’ commentary on Physics VIII where the Commentator argues for the necessity of secondary causes in order to refute an infinite chain of efficient causes.[43] Once again, Aquinas affirms that Averroes is correct: it is possible to conceive an infinite chain of secondary causes that are not related directly to the effect. And finally, in argument 8 Aquinas mentions that in Metaphysics IX Averroes has shown that motion is infinite in duration because of the infinite potency of the mover.[44] In other terms, motion has an infinite duration because God’s action is eternal. The latter is a common view in Avicenna and Averroes. Aquinas will assume it in his Commentary on the Sentences and in other works as Summa Contra Gentiles,[45] and especially, in the controversial treatise De aeternitate mundi. As it is known, in this work Aquinas discusses some arguments that have been formulated against the eternity of the world and he concludes that they are not defintive arguments or, in other words, they are not demonstrative. Hence, he argues for creation ab initio temporis. However, as Maimonides did, he affirms that it is impossible to demonstrate the doctrine of creation in time. For Aquinas, it is an article of faith.


In conclusion, although Aquinas coincides with the Arabs in considering God’s action as eternal, he makes clear that from this it is not necessary to conclude that therefore the effect exists from the eternity. This is just a possibility. However, the arguments of the Arabs are helpful because when trying to define the way in which God is related to the world, what they have really shown is that it is necessary to understand God as creator. In this sense, what the arguments for the eternity of the world prove is the necessity of an agent, a creator, whose action is eternal, but they do not demonstrate that the world has always existed. Nevertheless, Aquinas did not deny the possibility of an eternal created world. He considered the creation in time/eternity of the world debate an unsolved dialectical problem. But on the basis of faith, as he states in Summa Theologiae I, q. 46, a. 2, the world as having a beginning is an object of faith but not of demonstration (credibile, non autem scibile vel demonstrabile).







al-Ghazālī, The Incoherence of the Philosophers, M. Marmura (trans.), Utah: Brigham Young University Press, 1997.


Acar, Rahim, Talking about God and Talking about Creation, Leiden/Boston: Brill, 2005.


Adamson, Peter, “Two Early Arabic Doxographies on the Soul: al-Kindī and the Theology of Aristotle”, Modern Schoolman LXXVII, 2 (2000), pp. 105-125.

—The Arabic Plotinus: a Philosophical Study of the “Theology of Aristotle”, London: Duckworth, 2002.

—“Non-Discursive Thought in Avicenna’s Commentary on the Theology of Aristotle,” J. McGinnis (ed.), Interpreting Avicenna: Science and Philosophy in Medieval Islam, Leiden: Brill, 87–111, 2004.


Aquinas, Thomas, Pars Prima Summae theologiae, Romae: Ex Typographia Polyglotta S. C. de Propaganda Fide, 1888-1889.

Scriptum super libros Sententiarum magistri Petri Lombardi episcopi Parisiensis, t. 2., Ed. P. Mandonnet (P. Lethielleux, Parisiis, 1929).

Liber de veritate catholicae Fidei contra errores infidelium seu Summa contra Gentiles, Romae: Marietti, 1961.

De aeternitate mundi, Roma: Editori di San Tomasso, 1976, pp. 49-89.

Aquinas on Creation, Writings on the Sentences of Peter Lombard Book 2, Distinction 1, Question 1, S. Baldner and W. Carroll, (trans.), Toronto: Pontificial Institute of Medieval Studies, 1997.


Aristotle, The Complete Works of Aristotle, Jonathan Barnes (ed.), Princeton: Princeton University Press, 1984.


Asharí, The Theology of Al-Ash‘arī (Kitāb al-Luma‘), Richard C. McCarthy (trans.), Beirut: Imprimérie Catholique, 1953.


Averroes, Long Commentary on Aristotle’s Physics, Aristotelis Opera cum Averrois commentariis vol. IV, Venice, 1562.

On the Harmony of Religion and Philosophy, George F. Hourani (trans.), London: Luzac & Co., 1976.

The Incoherence of the Incoherence, Simon van den Bergh (trans.), London: E.J.B. Gibb Memorial, 1987.


Avicenna, Notes sur la “Théologie d’Aristote”, G. Vajda (trans.), Revue Thomiste LIX, LI, 1 (1951) , pp.346-406.

The Metaphysics of “The Healing”, M. Marmura (trans.), Utah: Brigham Young University Press, 1997.


Bertolacci, The reception of Aristotle’s Metaphysics in Avicenna's Kitab al-Shifa, Leiden/Boston: Brill, 2006.


Cruz Hernández, Miguel, “La Teología del Pseudo-Arisóteles (Kitāb Utūlūŷīya Li-Aristū) y la estructuración del neoplatonismo islámico”, Anuario Filosófico 33 (2000) pp. 87-110


D’ Ancona, Cristina, “Per un Profilo Filosofico dell’Autore Della ‘Theologia di Aristotele’”, Medioevo 17 (1991), pp.82-134.

“Pseudo-Theology of Aristotle, Chapter I: Structure and Composition”, Oriens, vol.36 (2001), pp.78-112.


Davidson, H. A., Proofs for Eternity, Creation and the Existence of God in Medieval Islamic and Jewish Philosophy, Oxford: Oxford University Press, 1987.


Glasner, Ruth, Averroes Physics, Oxford: Oxford University Press, 2009.


Hyman, Arthur, Averroes’ De Substantia Orbis, Massachusetts and Jerusalem, Cambridge, 1986.


Janssens, Jules, “Creation and Emanation in Ibn Sīnā”, Ibn Sīnā and his Influence on the Arabic and Latin World,  Great Britain: Ashgate, 2006 (originally printed in 1997), pp. 451-477.


Kretzmann, Norman, The Metaphysics of Creation, Aquinas’s Natural Theology in Summa Contra Gentiles II, Oxford: Clarendon Press, 1999.


Kogan, B. S., Averroes and the Metaphysics of Causation, New York: Columbia University Press, 1985.


MacDonald, Duncan B.,  Development of Muslim Theology, Jurisprudence and Constitutional Theory, New York: Russell & Russell, 1965.


Mahdi, Muhsin, “Alfarabi Against Philoponus”, Journal of Near Eastern Studies 26/4 (1967), pp. 233-260.


Maimonides, Moses, The Guide of the Perplexed, Shlomo Pines (trans.), 2 vols., Chicago: The University of Chicago Press, 1963.


Philoponus, On the Eternity of the World against Proclus, H. Rabe (ed.), Hildesheim: Olms, 1984.

Against Aristotle, On the Eternity of the World, Christian Wildberg (trans.), London: Duckworth, 1987.


Plotinus, Ennéades, Émile Bréhier (trans.), Paris: Société d’édition, 1963-1964.


Puig Motada, Epítome de Física, Madrid: Consejo Superior de Investigaciones Científicas/Instituto Hispano-Árabe de Cultura, 1987. 


Sorabji, Richard, The Philosophy of the Commentators (200-600 AD) vol. 2, Ithaca: Cornell University Press, 2005. [Simplicium in Phys., p. 179]  


Zimmermann, F. W, “The Origins of the So-Called Theology of Aristotle”, Warburg Institute Surveys and texts XI: Pseudo-Aristotle in the Middle Ages, London: Warburg Institute, 1986, pp.110-240.

[1] “Problems also include questions in regard to which deductions conflict (the difficulty then being whether so-and-so is so or not, there being convincing arguments for both views); others also in regard to which we have no argument because they are so vast, and we find it difficult to give our reasons, e.g. the question whether the universe is eternal or no; for into questions of that kind too it is possible to inquire” (Topics I, 11, 104b 12-16)

[2] The Theology of Pseudo-Aristotle is a fundamental treatise in order to understand the Islamic Neoplatonism. Cruz Hernández (2000: 87-110) made a comparative study between this treatise and  Enneads IV, V,  and VI. As it is known the Theology corresponds, although not literally, in numerous passages with Plotinus’ main work. See also Zimmermann (1986: 110-240), D’Ancona (2001: 78-112; 1991: 82-134), and Adamson (2002; 2004: 87-111).      

[3] Philoponus built three proofs for creation arguing the impossibility of an infinite number. The first one, the same that Simplicius reports, was used by most of the Islamic philosophers: al-Kindī and al-Ghazālī accepted it, but Avicenna, Averroes and Maimonides rejected it (Davidson 1987, 119-20).    

[4] When arguing for the restoration of the world, Ashari affirms in Against Deviators and Innovators: “God did not create them [the creatures] initially according to an antecedent exemplar. So if their initial creation was due solely to Him, He is not incapable of creating them anew” (§9, 1953: 10). Actually the first chapter of this treatise is devoted to demonstrate the necessity of a Creator of the world. 

[5] Avicenna uses different terms for emanation. J. Janssens (2006: 456) finds five terms: fayḍ, taǧallī, ṣudūr, inbi‘āṯ, and inbiǧās. The latter just appears twice in the Commentary on the Theologia Aristotelis. Thus, Janssens focuses his analysis on the first four terms. After a careful revision of each of them, he concludes that Avicenna is trying to avoid any pantheistic connotation by stressing that his emanation refers to the existing things as concomitants of God (2006: 468). In this sense, Avicenna takes some distance from the Neoplatonic understanding of emanation and seems to be more Aristotelian. At the same time, with the precise distinction between God and the world he opens the way to accept in some sense the notion of creation. Janssens (2006: 468) analyzes the terms used by Avicenna for creation: takwīn (generation), iḥdāṯ (origination), ḫalq (material creation), ibdā‘ (creation from nothing). Avicenna, as we will see, tries to harmonize emanation and creation. The most difficult to interpret is the way in which he used the term ibdā‘. It seems, as Janssens points out, that he was trying to express a genuine theory of creation ex nihilo (2006: 476). 

[6]  “(…) That which in itself is a necessary existent has no cause, while that which in itself is a possible existent has a cause. Whatever is a necessary existent in itself is a necessary existent in all its aspects. The existence of the Necessary Existent cannot be equivalent to the existence of another where each would equal the other as regards necessary existence, becoming [thereby] necessary concomitants. The existence of the Neccesary Existent cannot at all be a composite, [deriving] from multiplicity. The true nature of the Neccessary Existent can in no manner be shared by another. From our verifying [all] this, it follows necessarily that the Necessary Existent is not [dependent on] relation, is neither changing nor multiple, and has nothing associated with His existence that is proper to Himself” (al-Shifā’, al-Ilāhiyāt I, 6, 30).

[7] “(…) there is, for the whole, a Principle whose existence is necessary, [that is] neither included in genus nor is subject to definition or demonstration; [that He] is free from quantity, quality, quiddity, place, time, and motion; [that He] has neither equal, companion, nor contrary; that He is one in all respects because He is not divisible—neither in terms of parts in actuality, [nor] in terms of parts by supposition and estimation (as with the continuous), nor in the mind in that His essence is composed of varied intellectual ideas from which an aggregate becomes united; [and] that He is one inasmuch as He does not share at all [with others] the existence that belongs to Him. He is thus, by this unity, single. He is one because He is perfect in existence; nothing in Him awaits completion, this being one of the aspects of the one. The one is only in Him in the negative manner. [This is] unlike the one belonging to bodies—by reason of connection or combination—or to some other thing among [things] where the one is in it through a unity which is an existential meaning that appends itself to an essence or essences” (al-Shifā’, al-Ilāhiyāt IX, 1, 299).

[8] As Acar (2005: 140-146) has pointed out, for Avicenna there is nothing external nor internal that determine God to create. God knows himself and by making this, the existence of the things are necessarily concomitant to God’s essence.

[9] A few lines before Avicenna had rejected the possibility of an absolute creation: “Therefore, everything, with the exception of the One who in His essence is one and the existent who in His essence is an existent, acquires existence from another, becoming through it an existent, being in itself a nonexistent. This is the meaning of a thing’s being created—that is, attaining existence from another. It has absolute nonexistence which it deserves in terms of itself; it is deserving of nonexistence not only in terms of its form without its matter, or in terms of its matter without its form, but in its entirety. Hence, if its entirety is not connected with the necessitation of the being that brings about its existence, and it is reckoned as being dissociated from it, then in its entirety its nonexistence becomes necessary. Hence, its coming into being at the hands of what brings about its existence is in its entirety. No part of it, in relation to this meaning, is prior in existence—ncither its matter nor its form, if it possesses matter and form.

Hence, the whole, in relation to the first cause, is created. Its act of bringing into being that which comes to be from it would entirely rule out nonexistence in the substances of things. Rather, it is an act of bringing into existence that absolutely prevents nonexistence in things that bear perpetualness. This, then, is absolute creation. Bringing into existence [in the] absolute [sense] is not any kind of bringing into existence. And everything is originated from that One, that One being the originator of it, since the originated is that which comes into being after not having been.

[Now,] if this posteriority were temporal, then the antecedent precedes it and ceases to exist with its origination. The [antecedent] would, hence, be described as something that was before and is now no more. Hence, nothing would have become disposed to become originated unless there had been something before it that ceases to exist by its coming into existence. Thus, origination from absolute nonexistence—which is creation—becomes false and meaningless. Rather, the posteriority here is essential posteriority. For, the state of affairs that a thing possesses from itself precedes that which it has from another. If it has existence and necessity from another, then from itself it has nonexistence and possibility. Its nonexistence was prior to its existence, and its existence is posterior to nonexistence, [involving] a priority and posteriority in essence. Hence, in the case of everything other than the First, the One, its existence comes about after not having been—[a nonbeing] that it itself deserves” (al-Shifā’, al-Ilāhiyāt VIII, 3, 272-3).

[10] “The objection necessarily shows the falsity of the argumentation. The problematic facet is resolved in evaluating the objections and what is being demanded [of the opponent]. In this book we have undertaken only to muddy their doctrine and throw dust in the face of their proofs with that which would reveal their incoherence. We have not undertaken to defend a specific doctrine and thus have not departed from the purpose of this book. We will not go exhaustively into proofs for the [world’s] temporal creation, since our purpose is to refute their claim that they have knowledge of [its] pre-eternity” (Tahāfut al-falāsifa 134: 46).

[11] Ruth Glasner (2009: 93-5) finds a connection between the long commentary and the epitome. She mentions that there are relatively minor differences between the manuscripts (Cairo, Madrid, and according to Puig (1987: 61-95) terminology, the Oriental manuscripts). Both Glasner and Puig observe that there are some differences precisely at the beginning of book VIII. This suggests that perhaps Averroes worked several times on the interpretation of book VIII and especially in the succession argument. Given the technical character of Glasner’s remarks I will keep the argument in the way in which Aquinas himself understood it. 

[12] [3475] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 1. (…) Ex substantia caeli sic. Omne quod est ingenitum et incorruptibile, semper fuit et semper erit. Sed materia prima est ingenita et incorruptibilis; quia omne quod generatur, generatur ex subjecto, et quod corrumpitur, corrumpitur in subjectum; materiae autem primae non est aliquod subjectum. Ergo materia prima semper fuit et semper erit. Sed materia nunquam denudatur a forma. Ergo materia ab aeterno fuit perfecta formis suis, quibus species constituuntur; ergo universum ab aeterno fuit, cujus istae species sunt partes. Et haec est ratio Aristotelis in 1 Physic.

[13] [3476] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 2. Praeterea, quod non habet contrarium, non est corruptibile nec generabile; quia generatio est ex contrario, et corruptio in contrarium. Sed caelum non habet contrarium, cum motui ejus nihil contrarietur. Ergo caelum non est generabile nec corruptibile: ergo semper fuit et semper erit. Et haec est ratio philosophi in 1 caeli et mundi.

[14] [3477] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 3. Praeterea, secundum positionem fidei, substantia mundi ponitur incorruptibilis. Sed omne incorruptibile est ingenitum. Ergo mundus est ingenitus: ergo fuit semper. Probatio mediae. Omne quod est incorruptibile, habet virtutem quod sit semper. Sed illud quod habet virtutem quod sit semper, non invenitur quandoque ens et quandoque non ens; quia sequeretur quod simul esset ens et non ens: toto enim tempore aliquid est ens ad quod virtus sua essendi determinatur; unde si habet virtutem ut sit in omni tempore, in omni tempore est: et ita, si ponatur aliquando non esse, sequitur quod simul sit et non sit. Ergo nullum incorruptibile est quandoque ens et quandoque non ens. Sed omne generabile est hujusmodi. Ergo et cetera. Et haec est ratio philosophi in 1 de Cael. et Mund.

[15] [3478] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 4. Praeterea, omne quod alicubi est ubi prius nihil erat, est in eo quod prius fuit vacuum: quia vacuum est in quo potest esse corpus, cum nihil sit ibi. Sed si est mundus factus ex nihilo; ubi nunc est mundus, prius nihil erat. Ergo ante mundum fuit vacuum. Sed vacuum esse est impossibile, ut probatur in 4 Physic., et ut multa experimenta sensitiva demonstrant in multis ingeniis quae per hoc fiunt quod natura non patitur vacuum. Ergo impossibile est mundum incepisse. Et haec ratio est Commentatoris in 3 Cael. et Mund.

[16] [3479] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 5. Idem potest argui ex parte temporis sic. Omne quod est semper in principio et fine sui, semper fuit et semper erit: quia post principium est aliquid, et ante finem. Sed tempus semper est in eo quod est principium temporis et finis; quia nihil est temporis nisi nunc, cujus definitio est quod sit finis praeteriti, et principium futuri. Ergo videtur quod semper fuit tempus, et semper erit; et ita motus, et mobile, et totus mundus. Et haec est ratio philosophi in 8 Physic.

[17]  [3480] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 6. Praeterea, omne id quod nunquam potest demonstrari ut stans, sed semper ut fluens, habet aliquid ante se a quo fluit. Sed nunc non potest demonstrari ut stans, sicut punctus, sed semper ut fluens; quia ratio tota temporis est in fluxu et successione. Ergo oportet ante quodlibet nunc ponere aliud nunc: ergo impossibile est imaginari tempus habuisse primum nunc: ergo tempus semper fuit, et ita ut prius. Et haec est ratio Commentatoris ibidem.

[18] 3481] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 7. Praeterea, creator mundi aut praecedit mundum tantum natura, aut etiam duratione. Si natura tantum, sicut causa effectum; ergo quandocumque fuit creator, fuit creatura; et ita mundus ab aeterno. Si autem duratione; prius autem et posterius in duratione causat rationem temporis: ergo ante totum mundum fuit tempus: et hoc est impossibile; quia tempus est accidens motus, nec est sine motu. Ergo impossibile est mundum non semper fuisse. Et haec est ratio Avicennae in sua Metaph.

[19] [3482] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 8. Idem potest ostendi ex parte motus. Impossibile enim est novam relationem esse inter aliqua nisi aliqua mutatione facta circa alterum eorum; sicut patet in qualitate; non enim aliqua fiunt de novo aequalia, nisi altero extremorum augmentato vel diminuto. Sed omnis motus importat relationem moventis ad motum, quae relative opponuntur. Ergo impossibile est motum esse novum, nisi praecedat aliqua mutatio vel in movente vel in moto: sicut quod unum approximetur ad alterum, vel aliquid aliud hujusmodi. Ergo ante omnem motum est motus; et sic motus est ab aeterno, et mobile, et mundus. Et haec est ratio philosophi, in 8 Physic.

[20] [3483] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 9 Praeterea, omne illud cujus motus quandoque est et quandoque quiescit, reducitur ad aliquem motum continuum, qui semper est: quia hujus successionis, quae est ex vicissitudine motus et quietis, non potest esse causa aliquid eodem modo se habens; quia idem eodem modo se habens, semper facit idem. Ergo oportet quod causa hujus vicissitudinis sit aliquis motus qui non est semper; et sic oportet quod habeat aliquem motum praecedentem: et cum non sit abire in infinitum, oportet devenire ad aliquem motum qui semper est; et sic idem quod prius. Et haec ratio est Commentatoris in 8 Physic. Idem potest etiam extrahi ex verbis philosophi. Inducit etiam hanc rationem Commentator in 7 Metaph., ad ostendendum, quod si mundus esset factus, oporteret quod hic mundus esset pars alterius mundi, cujus motu accideret variatio in mundo isto, sive in vicissitudine motus et quietis, sive in vicissitudine esse et non esse.

[21] [3484] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 10. Praeterea, generatio unius est corruptio alterius. Sed nihil corrumpitur nisi generetur prius. Ergo ante omnem generationem est generatio, et ante omnem corruptionem corruptio. Sed haec non potuerunt esse, nisi mundo existente. Ergo mundus semper fuit. Et haec est ratio philosophi in 1 de generatione.

[22] [3485] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 11 Idem potest ostendi ex parte ipsius moventis vel agentis. Omnis enim actio vel motus quae est ab agente vel movente non moto, oportet quod sit semper. Sed primum agens vel movens est omnino immobile. Ergo oportet quod actio ejus et motus ejus sit semper. Prima sic probatur. Omne quod agit vel movet postquam non agebat vel movebat, educitur de potentia in actum, quia unumquodque agit secundum id quod est in actu: unde si agit postquam non agebat, oportet quod sit aliquid in actu in eo quod prius erat in potentia. Sed omne quod educitur de potentia in actum movetur. Ergo omne quod agit postquam non agebat, movetur. Et haec ratio potest extrahi ex verbis philosophi, in 8 Physic.

[23] [3486] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 12. Praeterea, Deus aut est agens per voluntatem, aut per necessitatem naturae. Si per necessitatem naturae, cum talia sint determinata ad unum, oportet quod ab eo semper idem fiat: unde si ab eo mundus est aliquando factus, necesse est mundum esse aeternum. Si autem agens per voluntatem; omnis autem voluntas non incipit agere de novo nisi aliquis motus fiat in volente, vel ab aliquo impediente, quod prius erat et postmodum cessat, vel ex eo quod excitatur nunc et non prius, aliquo inducente ad agendum quod prius non inducebat: cum ergo voluntas Dei immobiliter eadem maneat, videtur quod non incipiat de novo agere. Et ista ratio communiter est philosophi in 8 Physic., et Avicennae, et Commentatoris.

[24] [3487] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 13. Praeterea, omnis volens quandoque agere et quandoque non agere, oportet quod imaginetur tempus post tempus, discernendo tempus in quo vult agere, a tempore in quo non vult agere. Sed imaginari tempus post tempus, sequitur mutationem vel ipsius imaginationis, vel saltem imaginati, quia successio temporis causatur a successione motus, ut patet ex 4 Physic. Ergo impossibile est quod voluntas incipiat aliquem novum motum agere quem non praecedat alius motus. Et haec est ratio Commentatoris in 8 Physic.

[25] [3488] Super Sent., lib. 2 d. 1 q. 1 a. 5 arg. 14 Praeterea, omnis voluntas efficiendi statim producit effectum, nisi desit aliquid illi volito quod sibi postmodum adveniat; sicut si modo habeam voluntatem faciendi ignem cras quando erit frigus, modo isti volito deest praesentia frigoris, qua adveniente, statim faciam ignem, si possum, nisi ad hoc aliquid aliud desit. Sed Deus habuit voluntatem aeternam faciendi mundum; alias esset mutabilis. Ergo impossibile est quod ab aeterno non fecerit mundum, nisi per hoc quod aliquid mundo deerat quod postmodum advenit. Sed non potuit advenire nisi per actionem aliquam. Ergo oportet quod ante hoc de novo factum praecedat aliqua actio mutationem faciens; et ita a voluntate aeterna nunquam procedat aliquid novum, nisi motu mediante aeterno. Ergo oportet mundum aeternum semper fuisse. Et haec est ratio Commentatoris, ibidem.

[26] [3489] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 1. Sed contra, Deus aut est causa substantiae mundi, aut non, sed motus ejus tantum. Si motus tantum, ergo ejus substantia non est creata: ergo est primum principium; et sic erunt plura prima principia et plura increata, quod supra improbatum est. Si autem est causa substantiae caeli, dans esse caelo; cum omne quod recipit esse ab aliquo, sequatur ipsum in duratione, videtur quod mundus non semper fuerit.

[3490] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 2. Praeterea, omne creatum est ex nihilo factum. Sed omne quod est ex nihilo factum est ens postquam fuit nihil, cum non sit simul ens et non ens. Ergo oportet quod caelum prius non fuerit et postmodum fuerit, et sic totus mundus.

[27] [3491] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 3. Praeterea, si mundus fuit ab aeterno, ergo infiniti dies praecesserunt diem istum. Sed infinita non est transire. Ergo nunquam fuisset devenire ad hunc diem; quod falsum est: ergo et cetera.

[3492] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 4 Praeterea, cuicumque potest fieri additio, isto potest esse aliquid majus vel plus. Sed diebus qui praecesserunt, potest fieri dierum additio. Ergo tempus praeteritum potest esse majus quam sit. Sed infinito non est majus, nec potest esse. Ergo tempus praeteritum non est infinitum.

[3493] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 5 Praeterea, si mundus fuit ab aeterno, ergo et generatio fuit ab aeterno tam hominum quam animalium. Sed omnis generatio habet generans et generatum; generans autem est causa efficiens generati; et sic in causis efficientibus est procedere in infinitum, quod est impossibile, ut probatur in 2 Metaph. Ergo impossibile est generationem semper fuisse, et mundum.

[3494] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 6 Praeterea, si mundus semper fuit, homines semper fuerunt. Ergo infiniti homines sunt mortui ante nos. Sed homine moriente non moritur anima ejus, sed manet. Ergo modo sunt infinitae animae in actu a corporibus absolutae. Sed impossibile est infinitum esse in actu, ut in 3 Physic. probatur. Ergo impossibile est mundum semper fuisse.

[28]  [3495] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 7 Praeterea, impossibile est aliquid Deo aequiparari. Sed si mundus semper fuisset, aequipararetur Deo in duratione. Ergo hoc est impossibile.

[3496] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 8 Praeterea, nulla virtus finita, est ad operationem infinitam. Sed virtus caeli est virtus finita, cum magnitudo ejus finita sit, et impossibile sit a magnitudine finita esse virtutem infinitam. Ergo impossibile est quod motus ejus fuerit in tempore infinito, et similiter impossibile est ut esse ejus tempore infinito duraverit: quia duratio rei non excedit virtutem quam habet ad esse: et sic incepit quandoque.

[3497] Super Sent., lib. 2 d. 1 q. 1 a. 5 s. c. 9 Praeterea, nullus dubitat quin Deus natura praecedat mundum. Sed in Deo idem est natura et duratio sua. Ergo duratione Deus mundum praecedit. Ergo mundus non fuit ab aeterno.

[29] “Evidently there is a first principle, and the causes of things are neither an infinite series nor infinitely various in kind. For, on the one hand, one thing cannot proceed from another, as from matter, ad infinitum, e. g. flesh from earth, earth from air, from fire, and so on without stopping; nor on the other hand can the efficient causes form and endless series, man for instance being acted on by air, air by the sun, the sun by Strife, and so on without a limit. Similarly the final causes cannot go on ad infinitum (…)” (Metaphysics II, 2, 994a1-5).  

[30] In Physics III, 5 Aristotle argues that infinity cannot exist in actuality. Within this book, Aristotle is rejecting the possibility of a body being eternal.

[31] Dico ergo, quod ad neutram partem quaestionis sunt demonstrationes, sed probabiles vel sophisticae rationes ad utrumque. Et hoc significant verba philosophi dicentis quod sunt quaedam problemata de quibus rationem non habemus, ut utrum mundus sit aeternus; unde hoc ipse demonstrare nunquam intendit: quod patet ex suo modo procedendi; quia ubicumque hanc quaestionem pertractat, semper adjungit aliquam persuasionem vel ex opinione plurium, vel approbatione rationum, quod nullo modo ad demonstratorem pertinet. Causa autem quare demonstrari non potest, est ista, quia natura rei variatur secundum quod est in esse perfecto, et secundum quod est in primo suo fieri, secundum quod exit a causa; sicut alia natura est hominis jam nati, et ejus secundum quod est adhuc in materno utero. Unde si quis ex conditionibus hominis nati et perfecti vellet argumentari de conditionibus ejus secundum quod est imperfectus in utero matris existens, deciperetur; sicut narrat Rabbi Moyses, de quodam puero, qui mortua matre, cum esset paucorum mensium, et nutritus fuisset in quadam insula solitaria, perveniens ad annos discretionis, quaesivit a quodam, an homines essent facti, et quomodo; cuis cum exponerent ordinem nativitatis humanae, objecit puer hoc esse impossibile, asserens, quia homo nisi respiret et comedat, et superflua expellat, nec per unum diem vivere potest; unde nec in utero matris per novem menses vivere potest. Similiter errant qui ex modo fiendi res in mundo jam perfecto volunt necessitatem vel impossibilitatem inceptionis mundi ostendere: quia quod nunc incipit esse, incipit per motum; unde oportet quod movens praecedat duratione: oportet etiam quod praecedat natura, et quod sint contrarietates, et haec omnia non sunt necessaria in progressu universi esse a Deo.

[32] “No inference can be drawn in any respect from the nature of a thing after it has been generated, has attained its final state, and has achieved stability in its most perfect state, to the state of that thing while it moved toward being generated” (Guide II, 17, p. 295).

[33] [3499] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 1 Ad primum ergo dicendum est, quod materia est ingenita et incorruptibilis, non tamen sequitur quod semper fuerit: quia incepit esse non per generationem ex aliquo sed omnino ex nihilo; et similiter posset deficere si Deus vellet, cujus voluntate materiae et toti mundo esse communicatur.

[3500] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 2 Et similiter dicendum est ad secundum, quod illa ratio procedit de inceptione per generationem et motum; unde illa est ratio contra Empedoclem et alios, qui posuerunt caelum generari.

[3501] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 3 Ad tertium dicendum, quod potentia quae nunc est in caelo ad durationem non mensuratur ad determinatum tempus; unde per eam in ante et post potuit infinito tempore esse, si eam semper habuisset: sed hanc potentiam durationis non semper habuit, sed voluntate divina in sua creatione sibi tradita est.

[34]  [3502] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 4 Ad quartum dicendum, quod ante creationem mundi non fuit vacuum, sicut neque post: vacuum enim non est tantum negatio sed privatio; unde ad positionem vacui oportet ponere locum vel dimensiones separatas, sicut ponentes vacuum dicebant, quorum nullum ponimus ante mundum. Et si dicatur, quod possibile erat ante factionem mundi, mundum futurum esse ubi nunc est, dicendum ad hoc, quod non erat nisi in potestate agentis, ut supra dictum est.

[35]  [3503] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 5 Ad quintum dicendum, quod illa ratio est circularis, quod sic patet secundum philosophum. Per prius et posterius in motu, est prius et posterius in tempore; unde quando dicitur, quod omne nunc sit finis prioris, et posterioris principium, supponitur quod omne momentum motus sequatur quemdam motum, et praecedat quemdam. Unde dico, quod propositio illa non potest probari nisi ex suppositione ejus quod per eam concluditur; et ideo patet quod non est demonstratio.

[3504] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 6 Ad sextum dicendum, quod nunc nunquam intelligitur ut stans sed semper ut fluens; non autem ut fluens a priori, nisi motus praecedat, sed in posterius; nec iterum in posterius sed a priori, nisi motus sequatur. Unde si nunquam sequeretur vel praecederet motus, nunc non esset nunc: et hoc patet in motu particulari, qui sensibiliter incipit, cujus quodlibet momentum est fluens, et tamen aliquod est primum et aliquod ultimum, secundum terminum a quo et in quem.

[36]  [3505] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 7 Ad septimum dicendum, quod Deus praecedit mundum non tantum natura sed etiam duratione: non tamen duratione temporis, sed aeternitatis; quia ante mundum non fuit tempus in rerum natura existens, sed imaginatione tantum: quia nunc imaginamur huic tempori finito, ex parte ante Deum potuisse multos annos addidisse quibus omnibus praesens esset aeternitas; et secundum hoc dicitur quod Deus potuit prius facere mundum quam fecerit et majorem et plures.

[37] [3506] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 8 Ad octavum dicendum, quod novitas relationis contingit non ex mutatione moventis sed ex mutatione mobilis, ut large mutatio sumatur pro creatione quae proprie mutatio non est, ut dictum est supra. Unde motum caeli praecedit creatio ejus ad minus natura: creationem autem non praecedit aliqua mutatio, cum sit ex non ente simpliciter. Si tamen supponeretur quod etiam caelum extitisset antequam moveri coepisset, adhuc ratio non procederet: quia intelligendum est quod duplex est relatio. Quaedam est relatio absoluta, sicut in omnibus quae sunt ad aliquid secundum esse ut paternitas et filiatio; et talis relatio non efficitur nova nisi per acquisitionem illius in quo relatio fundatur; unde si acquiratur per motum, talis relatio sequitur motum; sicut similitudo unius ad alterum sequitur alterationem in qualitate supra quam fundatur relatio. Si autem acquiratur per creationem, sequitur creationem, sicut similitudo creaturae ad Deum fundatur super bonitatem quae per creationem acquiritur, per quam creatura Deo assimilatur. Quaedam autem relativa sunt quae simul important relationem et fundamentum relationis. Novitas autem talium relationum exigit acquisitionem illius rei quae significatur per nomen, sicut ipsius habitus qui est scientia; et similiter est de relatione quam importat nomen motus, quae efficitur nova per acquisitionem ipsius motus a movente in mobili.

[38] [3507] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 9 Ad nonum dicendum, quod hujusmodi vicissitudinis quod quandoque mundus non fuit et postmodum fuit, non est causa efficiens aliquis motus sed aliqua res semper eodem modo se habens, scilicet voluntas divina, quae ab aeterno fuit de hoc quod mundus in esse post non esse exiret. Et si diceretur, quod idem semper facit idem, dico, quod verum est, si accipiatur agens secundum propriam rationem, qua producit determinate hunc effectum. Sicut autem agens naturale determinatur per formam propriam, ut nunquam sequatur actio nisi secundum convenientiam ad formam illam; ita agens voluntarium determinatur ad actionem per propositum voluntatis; unde si voluntas non sit impedibilis nec mobilis, non sequitur effectus nisi secundum hoc quod voluntas proposuit; et hoc est verum quod voluntas divina in hoc quod semper est eadem, semper facit illud quod ab aeterno voluit, quia nunquam causatur; non tamen facit ut sua volita semper sint; quia hoc ipse non vult; unde si hoc faceret, quia faceret illud quod ipse non vult, esset simile ac si calor faceret frigus

[39] [3508] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 10 Ad decimum dicendum, quod prima individua generabilium et corruptibilium non prodierunt in esse per generationem, sed per creationem; et ideo non oportet quaedam praeextitisse ex quibus creata sint ut sic in infinitum abeatur.

[40] [3509] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 11 Ad undecimum dicendum, quod est duplex agens. Quoddam per necessitatem naturae; et istud determinatur ad actionem per illud quod est in natura ejus; unde impossibile est quod incipiat agere nisi per hoc quod educitur de potentia ad actum, vel essentiali vel accidentali. Aliud est agens per voluntatem, et in hoc distinguendum est: quod quoddam agit actione media quae non est essentia ipsius operantis; et in talibus non potest sequi effectus novus sine nova actione, et novitas actionis facit aliquam mutationem in agente prout est exiens de otio in actum, ut in 2 de anima dicitur. Quoddam vero sine actione media vel instrumento, et tale agens est Deus; unde suum velle est sua actio; et sicut suum velle est aeternum, ita et actio: non tamen effectus sequitur nisi secundum formam voluntatis, quae proponit sic vel sic facere; et ideo non exit de potentia in actum; sed effectus qui erat in potentia agente, efficitur actu ens.

[3510] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 12 Ad duodecimum dicendum, quod in omnibus illis quae agunt propter finem qui est extra voluntatem, voluntas regulatur secundum illum finem; unde secundum ea quae impediunt et juvant ad finem, vult quandoque agere et quandoque non agere. Sed voluntas Dei non dedit esse ipsi universo propter alium finem existentem extra voluntatem ejus, sicut nec movet propter alium finem, ut philosophi concedunt, quia nobilius non agit propter vilius se; et ideo non oportet ex hoc quod non semper agat, quod habeat aliquid inducens et retrahens, nisi determinationem voluntatis suae, quae ex sapientia sua omnem sensum excedente procedit.

[3511] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 13 Ad decimumtertium dicendum, quod intellectus divinus intelligit omnia simul; et ideo ex hoc quod intelligit praesentia hujus temporis et illius, non est aliqua mutatio in intellectu ejus, licet hoc non possit contingere in intellectu nostro; et ideo patet quod ratio sophistica est. Similiter nec ponitur aliquis motus ex parte rei imaginatae, quia Deus noluit facere universum post aliquod tempus; quia tempus ante non erat nisi imaginatum, ut prius dictum est.

[3512] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad 14 Ad decimumquartum dicendum, quod voluntas divina non ab aeterno produxit universum, quia aliquid deerat ipsi volito: hoc enim quod volito potest intelligi deesse propter quod differtur, est proportio ipsius ad finem; sicut voluntas hominis differt sumere medicinam, quando medicina non est proportionata sanitati hominis; et sic dico quod ipsi universo quod fieret ab aeterno, deerat proportio ad finem, quae est voluntas divina: hoc enim voluit Deus ut haberet esse post non esse, sicut natura ita et duratione; et si ab aeterno fuisset, hoc sibi defuisset; unde non fuisset proportionatum divinae voluntati quae est finis ejus.


[41] [3514] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad s. c. 2 Ad secundum respondet Avicenna in sua metaphysica: dicit enim omnes res a Deo creatas esse, et quod creatio est ex nihilo, vel ejus quod habet esse post nihil. Sed hoc potest intelligi dupliciter: vel quod designetur ordo durationis, et sic secundum eum falsum est; aut quod designetur ordo naturae, et sic verum est. Unicuique enim est prius secundum naturam illud quod est ei ex se, quam id quod est ei ab alio. Quaelibet autem res praeter Deum habet esse ab alio. Ergo oportet quod secundum naturam suam esset non ens, nisi a Deo esse haberet; sicut etiam dicit Gregorius quod omnia in nihilum deciderent, nisi ea manus omnipotentis contineret: et ita non esse quod ex se habet naturaliter, est prius quam esse quod ab alio habet, etsi non duratione; et per hunc modum conceduntur a philosophis res a Deo creatae et factae.

[42] [3513] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad s. c. 1 Et quia ad rationes in contrarium factas, quas dixi demonstrationes non esse, inveniuntur philosophorum responsiones; ideo quamvis verum concludant, ad eas etiam respondendum est, secundum quod ipsi philosophi respondent, ne alicui disputanti contra tenentes aeternitatem mundi ex improviso occurrant. Ad primum ergo dicendum, quod sicut dicit Commentator in Lib. de substantia orbis, Aristoteles nunquam intendit quod Deus esset causa motus caeli tantum, sed etiam quod esset causa substantiae ejus dans sibi esse. Cum enim sit finitae virtutis, eo quod corpus est, indiget aliquo agente infinitae virtutis, a quo et perpetuitatem motus habeat, et perpetuitatem essendi, sicut motum et esse. Non tamen ex hoc sequitur quod praecedat duratione: quia non est dans esse per motum, sed per influentiam aeternam, secundum quod scientia ejus est causa rerum; et ex hoc quod scit ab aeterno et vult, sequitur res ab aeterno esse; sicut ex hoc quod sol est ab aeterno, sequitur quod radius ejus ab aeterno sit.

[43] [3517] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad s. c. 5 Ad quintum dicendum, quod eumdem effectum praecedere causas infinitas per se, vel essentialiter, est impossibile; sed accidentaliter est possibile; hoc est dictu, aliquem effectum de cujus ratione sit quod procedat a causis infinitis, esse impossibilem; sed causas illas quarum multiplicatio nihil interest ad effectum, accidit effectui esse infinitas. Verbi gratia, ad esse cultelli exiguntur per se aliquae causae moventes, sicut faber, et instrumentum; et haec esse infinita est impossibile, quia ex hoc sequeretur infinita esse simul actu; sed quod cultellus factus a quodam fabro sene, qui multoties instrumenta sua renovavit, sequitur multitudinem successivam instrumentorum, hoc est per accidens; et nihil prohibet esse infinita instrumenta praecedentia istum cultellum, si faber fuisset ab aeterno. Et similiter est in generatione animalis: quia semen patris est causa movens instrumentaliter respectu virtutis solis. Et quia hujusmodi instrumenta, quae sunt causae secundae, generantur et corrumpuntur, accidit quod sunt infinitae: et per istum etiam modum accidit quod dies infiniti praecesserint etiam istum diem: quia substantia solis ab aeterno est secundum eos, et circulatio ejus quaelibet finita. Et hanc rationem ponit Commentator in 8 Physic.

[44] [3520] Super Sent., lib. 2 d. 1 q. 1 a. 5 ad s. c. 8 Ad octavum dicendum, quod in caelo non est potentia ad esse, sed ad ubi tantum, secundum philosophum: et ideo non potest dici, quod potentia ad esse sit finita vel infinita: sed potentia ad ubi finita est. Nec tamen oportet quod motus localis, cui correspondet haec potentia, sit finitus: quia motus est infinitus duratione ab infinitate virtutis moventis, a qua fluit motus in mobile. Et haec est ratio Commentatoris, in 11 Metaph.: tamen hoc quod dicit, quod non habet potentiam ad esse, intelligendum est, ad acquirendum esse per motum; habet tamen virtutem vel potentiam ad esse, ut dicitur in 1 Cael. et Mund., et haec virtus finita est; sed acquiritur duratio infinita ab agente separato infinito, ut ipsemet dicit.

[45] “Effectus procedit a causa agente per actionem eius. Sed actio Dei est aeterna: alias fieret de potentia agente actu agens; et oporteret quod reduceretur in actum ab aliquo priori agente, quod est impossibile. Ergo res a Deo creatae ab aeterno fuerunt” (Summa Contra Gentiles, II, 32, 4). Kretzmann (1999: 161ff) discusses this passage and Aquinas’ doctrine of creation in Summa Contra Gentiles II.