Placing Aquinas in the same category as Leibniz, J.F. Ross claims that Aquinas’ understanding of God's perfection and God's freedom to create are incompatible. Ross argues that “Aquinas interprets the statement ‘God is absolutely perfect’ in a way incompatible with the statement ‘God's decision might have been different from what it was.’”Footnote 1 Footnote 2 Footnote 3 Claiming that Aquinas rejects the notion of a ‘best possible world’, Klaas J. Kraay mentions that Aquinas and others holding to this position fall prey to the ‘problem of no best world’. Kraay includes Aquinas with philosophers who “have suggested that perhaps there are no unsurpassable worlds, but that instead there is an infinite hierarchy of increasingly better worlds.”Footnote 4 Kraay mentions that a major objection to this concept is that it “precludes perfect being theism, since no matter which world a putatively unsurpassable being actualizes, that being could be surpassed by a being who (all else equal) actualizes a better world.”Footnote 5
However, it seems that Aquinas’ position is being misrepresented in this debate. In this essay, I will explore Aquinas’ position regarding best possible worlds and defend it against the problem of no best world. First, I will review objections to Aquinas’ position. Next, I will explain concepts from Aquinas’ writings that have been overlooked, which have implications for the concept of a best possible world. Finally, after explaining the implications of these concepts regarding a best possible world, I will discuss how Aquinas’ position avoids the problem of no best world.
Objections to Aquinas
As mentioned above, Ross argues that Aquinas’ concepts of God's perfection and God's freedom to create are incompatible. Ross believes that Aquinas’ writings entail that God must create a best possible world.Footnote 6 Ross emphasizes Aquinas’ arguments in the Summa Theologiae (ST) regarding God's freedom and God's will. In ST I, 19, 3, Aquinas argues that the only thing God necessarily wills is His own goodness and God has a free choice to will the existence of anything else but Himself. In ST I, 19, 2, Aquinas argues that God must communicate His goodness to other beings as far as possible. Ross takes this to mean that God's will is such that He must create the best possible world, which is incompatible with Aquinas’ belief that God has free will in creating. Ross concludes that “Thomas Aquinas concurs with Leibniz and Spinoza in premises which entail that anything that is such that it is impossible that God should will its existence, is impossible absolutely. All worlds other than the actual fulfill that condition, given what has just been reported; therefore the actual world is the only possible world.”Footnote 7 Thus, Ross places Aquinas in the same category as Leibniz in making the case that the actual world is the best possible world and the only world that God would choose to create.
Elsewhere, Kraay mentions three theistic positions regarding best possible worlds. He says that theists either argue that (1) “there is exactly one unsurpassable world,” (2) “there are multiple unsurpassable worlds,” or (3) “there are no unsurpassable worlds.”Footnote 8 As mentioned above, Kraay places Aquinas in category (3) and goes on to mention that this category is susceptible to the problem of no best world.Footnote 9
The problem of no best world was formulated by William Rowe in 1993.Footnote 10 The problem emphasizes that if there is a better world that a being could have created, it seems possible that there could be a morally better being. This is a problem for category (3) theists because if God is a perfect being and morally unsurpassable, then God should not be able to create a world if there could be a better world. If God is perfect and there is no such thing as a best possible world, then God should never decide to create.Footnote 11
If Kraay is correct, and all category (3) positions fall prey to the problem of no best world, then Aquinas’ writings need to entail propositions that are foundational to the problem of no best world:
- NBW
- For every world w that is within God's power to actualize, there is a better world, x, that God has the power to actualize instead.
- P1
- If it is possible for the product of a world-actualizing action performed by some being to have been better, then, ceteris paribus, it is possible for that being's action to have been (morally or rationally) better.
- P2
- If it is possible for the world-actualizing action performed by some being to have been (morally or rationally) better, then, ceteris paribus, it is possible for that being to have been better.
- G
- There possibly exists a being who is essentially unsurpassable in power, knowledge, goodness, and rationality.Footnote 12
However, it will be shown that Aquinas does not necessarily hold to all of these. He most likely would have rejected P1 and P2.
Of course, if Ross is correct and Aquinas holds to a position similar to Leibniz the problem of no best world will be no problem for Aquinas. However, in the interest of fully explaining Aquinas’ position, I intend to show that Ross is mistaken and that Aquinas does not agree with Leibniz. To do so it will be necessary to discuss Aquinas’ views of God's purpose for His creation.
God's Purpose for the Universe
Aquinas’ discussion on God's will in the Summa contra Gentiles (SCG) has important implications for the purpose of His creation.Footnote 13 In SCG I, 74, he concludes that God wills His own goodness. Aquinas explains that “The understood good is the object of the will, as has been said. But that which is principally understood by God is the divine essence, as was proved above. The divine essence, therefore, is principally the object of the divine will.”Footnote 15 Given that the understood good is the object of the will, God wills Himself because He is Infinite GoodnessFootnote 16 and perfectly understands Himself.Footnote 17 Goodness (that which is desirable) and existence are interchangeableFootnote 18 and God must will Himself because He is Infinite Existence (e.g. infinitely desirable).Footnote 19
For those unfamiliar with Aquinas, it might sound strange for him to say that God wills Himself. Aquinas explains that there are two ways that a person can will something depending on whether or not the person possesses the good they desire:
To seek perfection belongs differently to those that have it and those that have it not. For those that have it not tend by desire, through the appetitive power proper to them, to acquire what is lacking to their desire, whereas those that have it rest in it. Hence, this cannot be lacking to the first being, which is God.Footnote 20
After comprehending the good, a person wills the good. If that person does not possess the willed good, then his willing it consists of performing actions to obtain it. If that person possesses the willed good, then his willing it consists of resting in (e.g. delighting in) the possession of the good. Just because a person possesses the good he desires does not mean that he any less wills the obtained good. So because God has will and perfectly understands His infinite goodness, He rests in and delights in His goodness (i.e. He wills His own goodness).
After explaining that God wills His own goodness, Aquinas moves on to discuss that God can will things other than Himself at SCG I, 75. This is necessary because it would seem that if God delights in Infinite Goodness, it would be unnecessary for Him to will any good apart from Himself.Footnote 21 In this regard, Aquinas emphasizes that when willing an end it is possible to will means to the end that are not necessary.Footnote 22 To borrow Aquinas’ illustration, someone can choose to ride a horse when willing to make a short trip although walking is all that is required.Footnote 23 Walking to the destination is required and must be willed, at a minimum, if the trip is to be made. However, although riding a horse is not necessary for a short trip, riding could be willed for a particular reason.
So it would seem that God needs a certain reason for willing things other than Himself and Aquinas finds this in God's goodness. Aquinas believes that God wills to create things other than Himself because of the Dionysian principle that the good is naturally diffusive of itself. He mentions that “…it belongs to the essence of goodness to communicate itself to others, as is plain from Dionysius (Div. Nom. iv). Hence it belongs to the essence of the highest good to communicate itself in the highest manner to the creature… .”Footnote 24 Garrigou-Lagrange expounds on this concept:
Goodness is essentially communicative; good is diffusive of itself. In the material order, we observe that, the sun imparts its light and vivifying heat to all that comes in contact with it. In the intellectual order, when the intellect has arrived at the knowledge of truth, it spontaneously seeks to impart this to others. In the moral order, those with a holy ardor for goodness, like the Apostles, have no rest until these same aspirations, this same love, are aroused in others.Footnote 25
Goodness is found to be naturally diffusive throughout creation including the material, mental, and moral realms. So although God has no need to will any goodness in addition to the Infinite Goodness in which He delights, He can decide to create a world to which He can communicate His goodness. God's infinite perfection entails that making creatures adds nothing to His goodness, but this does not mean that He cannot decide to create a world if He is inclined to do so.
Given these considerations, it seems that the only possible end or purpose God could have for His creation is His goodness. God's pure actuality entails that His one act can only consist of willing His own goodness.Footnote 26 If God wants to create something, He cannot create it for its own sake, but for the sake of His goodness. However, Aquinas explains that in necessarily willing God's goodness, He has the choice to will creatures apart from Himself that also have His goodness as their end.Footnote 27 God willing His own goodness is analogous to willing to take a trip and His willing the good of creatures ordered to the same end is analogous to choosing to ride a horse (because He chooses to communicate His goodness). In other words, the purpose of the world is for God to communicate His goodness to things other than Himself.Footnote 28 This has important implications regarding the type of universe that God must create.
Aquinas and the Best Possible World
Aquinas’ writings entail that, in a way, God cannot create a best possible world. This is for at least two reasons. First, God cannot create an infinitely perfect world because the only thing that is infinitely perfect is God. Given this, there can be no best possible world in terms of quantitative and qualitative goodness because for any given world, there is another world in which we can imagine something greater with more goodness.
Aquinas mentions the first reason in SCG II. While discussing certain things that it would be impossible for God to do, Aquinas argues that it would be impossible for God to create something equal to Himself.Footnote 29 He says, “…God cannot make a thing equal to Himself; for a thing whose being does not depend on another is superior in being, and in the other perfections, to that which depends on something else, such dependence pertaining to the nature of that which is made.”Footnote 30 For God to create something infinitely perfect, it would have to be Pure Actuality. But this rules out any possibility of God creating something infinitely perfect because every created thing is contingent and possesses potencies.
Moreover, the essence and existence of every created thing must be conjoined, which is a less perfect mode of existence than God. Therefore, God cannot create something infinitely perfect. Aquinas explains what this means for the universe that God chooses to create:
…created things cannot attain to a perfect likeness to God according to only one species of creature. For, since the cause transcends the effect, that which is in the cause, simply and unitedly, exists in the effect in composite and multiple fashion—unless the effect attain to the species of the cause; which cannot be said in this case, because no creature can be equal to God. The presence of multiplicity and variety among created things was therefore necessary that a perfect likeness to God be found in them according to their manner of being.Footnote 31
In other words, God created to communicate His infinite goodness, but because nothing but God is infinitely perfect, He cannot communicate His goodness through creating a perfect likeness of Himself. So He must create a world with vast diversity and a hierarchy of being to best communicate His goodness. But no matter how much He creates or how diverse His creation is, it will never perfectly represent Him.
This eliminates the possibility of God creating an infinitely perfect world. But this does not mean that God cannot create a world that is perfect in some way. With infinite perfection eliminated as a possibility, the only way a world could be perfect is if it is a perfect instance of its kind. Aquinas discusses this when he says that
…if each thing tends toward a likeness of divine goodness as its end, and if each thing becomes like the divine goodness in respect of all the things that belong to its proper goodness, then the goodness of the thing consists not only in its mere being, but in all the things needed for its perfection, as we have shown. It is obvious, then, that things are ordered to God as an end, not merely according to their substantial act of being, but also according to those items which are added as pertinent to perfection, and even according to the proper operation which also belongs to the thing's perfection.Footnote 32
In other words, something can be said to possess perfection in that it exists and also if it fully actualizes its purpose. A world that fully actualizes its purpose can be said to be a perfect world. Thus, a world that communicates God's goodness to the degree that He determines will be a perfect world.
Aquinas believes that it would be impossible for there to be a best perfect world, however, because no possible finite world can completely communicate God's infinite goodness. This is entailed by Aquinas’ argument in SCG II, 45. Kretzmann offers an analogy that explains this concept well:
In creating, God undertakes to represent simple, eternal, perfect goodness in a composite, temporal, necessarily imperfect medium. It's like undertaking to represent a geometer's straight line (which is continuous, infinite, and invisible) by nothing but pencilled dots. Preserving the perfection of the order of these elements would require that any additional representational dots occur in positions that preserve the representation of the line's one-dimensional straightness. The addition of dots to the representation in that way could be said to improve the dotty representation, to enhance its capacity for conveying the nature of the invisible, continuous, straight, one-dimensional thing (visibly, discontinuously, not perfectly straightly, in pencilled dots that have at least two dimensions apiece). But, of course, there can't be a theoretically best representation of that sort.Footnote 33
When God creates He cannot create something that completely represents His goodness. Even an infinite creation with an infinite amount of good creatures would fall short of fully communicating God's goodness. Thus, there can be no best possible world that fulfills His purpose for creation.
However, Aquinas emphasizes that God can perfectly order the world to Himself to fulfill His purpose for creating it.Footnote 34 In other words, God can perfectly order a world so that it fulfills its intended purpose of communicating His goodness and attains its perfection. Aquinas explains this concept:
For as “it belongs to the best to produce the best,” it is not fitting that the supreme goodness of God should produce things without giving them their perfection. Now a thing's ultimate perfection consists in the attainment of its end. Therefore it belongs to the Divine goodness, as it brought things into existence, so to lead them to their end: and this is to govern…For since the end of the government of the world is that which is essentially good, which is the greatest good; the government of the world must be the best kind of government.Footnote 35, Footnote 36
So although God cannot create a best perfect world, He can create a world that communicates His goodness by creating a world that is perfectly ordered for this purpose.
Here it will be good to briefly discuss what Aquinas means by perfectly ordering the world. Aquinas explains this in SCG III, 17:
Again, order among ends is a consequence of order among agents, for, just as the supreme agent moves all secondary agents, so must all the ends of secondary agents be ordered to the end of the supreme agent, since whatever the supreme agent does, He does for the sake of His end. Now, the supreme agent does the actions of all inferior agents by moving them all to their actions and, consequently, to their ends. Hence, it follows that all the ends of secondary agents are ordered by the first agent to His own proper end.Footnote 37
For God to perfectly order the world is for God, as the First Agent of all things, to determine the final causes of all things, create and sustain their natures, and move them to their ends.
The order Aquinas is mentioning is the collective final causes of every substance in the universe. All final causes are determined by God and actualized through the natures of all substances and God's per se series of efficient causation in the world. The nature of every substance is determined for it to play a role in the perfection of the entire universe, which consists of communicating God's goodness. As the First Mover, God uses efficient causality to ‘pull’ all things to their final causes and their ultimate final cause, which is God and His purpose for creation.
One more digression is needed here. Aquinas argues that because God intends to communicate His goodness, God must include rational beings in His creation.Footnote 38 Aquinas concludes this for several reasons including that God must create beings with an intellect and will because God has an intellect and will.Footnote 39 Another reason is that if God wants to communicate His goodness, it is not only necessary to communicate being to creatures, but also to make creatures that can know His goodness.Footnote 40 In other words, there needs to be someone capable of understanding the message. If God failed to communicate the knowledge of His goodness, then He would fail to fully communicate His goodness.
This entails that human beings are, in a way, the purpose of all creation because they exist to fulfill God's purpose. Thus, within the hierarchy of beings that God creates, all of the lower beings have final causes that are ordered to the perfection of the beings above them. Aquinas explains that “…elements exist for the sake of mixed bodies; these latter exist for the sake of living bodies, among which plants exist for animals, and animals for men. Therefore, man is the end of the whole order of generation.”Footnote 41
What all of this entails is that, for God's purpose, a perfectly ordered world will consist of a hierarchy of beings, in which the final causes of all the beings are ordered to actualize rational beings. There must be a diverse and abundant hierarchy of beings that will represent God's goodness in being (to the imperfect degree that it can). Also, the hierarchy must be ordered so that it is conducive for the creation, subsistence, and perfection of rational creatures. This seems to be exactly what is found in our world. For decades, scientists have known that the cosmological constants and many other factors of our universe are ‘finely-tuned’ to permit intelligent life.Footnote 42 For example, if gravity were stronger or weaker by one part in 1040, stars like our sun (and thus humanity) could not exist.Footnote 43
So it is the order of the world that God creates that determines if it is a perfect world. In reference to Aquinas’ second argument against a best possible world, Aquinas argues that there cannot be a best possible world in terms of quantitative and qualitative goodness because for any given world we can imagine a world with one more good thing in it.Footnote 44 He mentions this in ST I:
The universe, the present creation being supposed, cannot be better, on account of the most beautiful order given to things by God; in which the good of the universe consists. For if any one thing were bettered, the proportion of order would be destroyed; as if one string were stretched more than it ought to be, the melody of the harp would be destroyed. Yet God could make other things, or add something to the present creation; and then there would be another and a better universe.Footnote 45
Aquinas here mentions two different senses of the term ‘better’. To make the universe better in one way, all God would need to do is add a creature or make creatures with greater abilities than the creatures He decided to create. This would add to the goodness of the universe as far as God communicates being. However, this would make the universe worse in another way because it would disturb the perfect order that God initially established. For example, as mentioned above, if the amount of mass in the universe were increased by a fraction, then humanity would not exist and God's purpose would not obtain.
So any given world will be perfected through the means of its order and not the quantity of good beings it contains. This entails that there cannot be a best perfect world because the number of quantitatively/qualitatively greater worlds is infinite. So although it is logically impossible for God to create a best perfect world, God can create a best possible world out of all of the possible arrangements of any particular world given its quantity and quality of substances.Footnote 46
However, it is not God's purpose to create a best perfect world. Instead, as mentioned above, it is God's purpose to create a world that will communicate His goodness: a perfectly ordered world. So Aquinas agrees that God will “produce the best.” However, when he says “the best” he is referring to the order of a world, not the quantity and quality of the world's substances. A ‘best possible world’ to Aquinas would be any particular world that is perfectly ordered to God given the substances it contains. So Aquinas concludes that for any world God decides to create, God will create a teleologically best world.
Implications for Objections to Aquinas
It should be apparent at this point why Ross is mistaken on what Aquinas’ writings entail regarding a best possible world. Ross concludes that Aquinas believes God must create a best possible world because Aquinas argues that God must communicate His goodness as far as possible.Footnote 47 However, Ross fails to account for Aquinas’ argument that nothing but God is infinitely perfect and God cannot create a world that perfectly represents His goodness. God cannot create a perfect likeness of Himself and there are an infinite number of worlds with varying quantities and qualities of goodness.
Thus, Ross’ conclusion, that Aquinas’ concepts of God's perfection and God's free will in creating are incompatible, is incorrect. The nature of contingent being is such that it metaphysically precludes God from creating anything infinitely perfect. Moreover, the nature of contingent being metaphysically precludes the possibility of God creating a best perfect world that best communicates His goodness. Therefore, differing with Leibniz’ understanding of God, Aquinas believes that God can create any possible world He chooses as long as He perfectly orders that world to communicate His goodness.
So Kraay, in a sense, is correct to say that Aquinas believes that there is no unsurpassable world that God can create. Aquinas does believe that God cannot create a world that has an unsurpassable quantity or quality of goodness. But the world that God chooses to create is unsurpassable in that its ordering to God's goodness is perfect or “the best.” But this does not mean that Aquinas is susceptible to the problem of no best world.
Aquinas would reject propositions P1 and P2 of the problem of no best world. This is because Aquinas understands the term ‘better world’ in proposition NBW differently than what is usually meant in the contemporary debate. As shown, when Aquinas says that God could create a better world, Aquinas means that God could have created a world that has a larger quantity or quality of goodness. However, a world with more substances is not a better world in that it does not fulfill its purpose to a higher degree than the actual world.Footnote 48
Thus, proposition P1 does not apply to Aquinas’ position and this means that P2 does not apply either. If God's purpose is to communicate His goodness, then He is not logically or morally obligated to create a best world with the highest quantity and quality of goodness. All He is required to do is create a world that fulfills His purpose. Thus, the problem of no best world dissolves because God can choose to create any world that is perfectly ordered to His goodness. There can be an infinite number of worlds with more and better substances, but God is not less perfect for choosing to create a world than which greater can be conceived.
At this point, it might be objected that I am misrepresenting the problem of no best world. One of Rowe's biggest points of emphasis in the problem of no best world lies in proposition P1. Rowe argues that if a being creates a world that could have been morally better (i.e. a world with less suffering or more happiness), that being cannot be an absolutely perfect being. For example, after mentioning that theism often includes the idea that God is morally perfect, Rowe explains that
If, no matter what world an omnipotent being creates, there is a morally better world that being can create, then, provided that the omnipotent being creates a significantly good world, it cannot be morally at fault for not having created a morally better world. But our question is whether a being in such a situation can be an absolutely perfect being. And for reasons I have already uncovered, I think the answer is no. A being is necessarily an absolutely perfect being only if it is not possible for there to be a being morally better than it. If a being creates a world when there is some morally better world that it could have created, then it is possible that there be a being morally better than it.Footnote 49
So it might be objected that Aquinas still falls prey to the problem of no best world because if God does not create the morally best world, then God cannot be said to be an absolutely perfect being.
However, it is debatable whether or not Aquinas believes that God's infinite perfection includes moral perfection and that God is a moral agent.Footnote 50 Aquinas believes that God is infinitely perfect because God is Pure Actuality and is not limited in any way. But to be a moral agent is to be limited by a moral law. So it is hard to see how Aquinas could believe that God is a moral agent if morality entails being limited by moral rules. Indeed, Aquinas emphasizes that there is no law above God when he says that
Since good as perceived by intellect is the object of the will, it is impossible for God to will anything but what His wisdom approves. This is, as it were, His law of justice, in accordance with which His will is right and just. Hence, what He does according to His will He does justly: as we do justly what we do according to law. But whereas law comes to us from some higher power, God is a law unto Himself.Footnote 51
Certainly Aquinas believes that the phrases “God is good,” and “a just man is good” have two different, but analogous meanings. God is good because He possesses all metaphysical perfections. A just man is good because he not only exists, but also because he follows the moral law that God created. But God created the moral law to guide rational creatures to their ultimate end.Footnote 52 Without creation, there would be no moral law as we know it. And if this were so, it is hard to see how God could be said to be a morally perfect agent if no moral law existed.
This is why it is so difficult for contemporary theists, who believe that God is a moral agent, to reconcile God's nature with the existence of evil. As a human being, if I had the power to stop all of the evil in the world with no harm or loss coming to myself, most would agree that it would be wrong for me to refrain from using this power. If God is subject to the same moral rules as humans, then it seems He would never allow moral and natural evils to occur because He could easily prevent them.
Aquinas' understanding of God's infinite goodness is that God is Infinite Existence and therefore infinitely desirable. This definition does not necessarily include morality. This is especially because for humans, acting morally is acting the way they are supposed to act. But in this life, humans are incapable of fully knowing God's essence because He is transcendent and infinite.Footnote 53 It is known how humans are supposed to act, but no person could possibly know how God ought to act. So it is likely that Aquinas did not believe that God is a moral agent.
This, however, does not mean that Aquinas’ position falls prey to the Euthyphro dilemma. Given that God is not a moral agent, it might be suggested that God could arbitrarily command humans to do evil. On the contrary, God commands things because they are conducive to His purpose of communicating His goodness. His moral law guides people to flourish as human beings and to cultivate virtues, such as love, that imitate His goodness. But He would never do anything that He prohibits humans from doing because this would contradict His own eternal law (from which the moral law originates) and therefore would contradict His purpose for creating. Aquinas explains:
Now God cannot be directly the cause of sin, either in Himself or in another, since every sin is a departure from the order which is to God as the end: whereas God inclines and turns all things to Himself as to their last end, as Dionysius states (Div. Nom. i): so that it is impossible that He should be either to Himself or to another the cause of departing from the order which is to Himself.Footnote 54
God is logically obligated to refrain from lying, murdering, and breaking covenants, etc. If He did such things He would be contradicting His own purposes. So while God is not subject to a moral law, His moral commands are not arbitrary, but are intended to guide rational creatures to their ultimate end.
Getting back to the possible objection that I am misrepresenting the problem of no best world, it is good to note that Rowe's argument assumes that theism entails that God is morally perfect. Rowe was not directing his argument toward Aquinas in particular. However, if this objection were aimed at Aquinas, it would fail because according to Aquinas’ position God's intention is to communicate His goodness and not to create a morally unsurpassable world. On the contrary, Aquinas would reject the idea that a morally better world would communicate God's goodness to a higher degree. In several places Aquinas mentions that some goods would be impossible without particular evils. For example, Aquinas mentions that animal death is a necessary evil if God wants to include lions in creation.Footnote 55 While the loss of a gazelle is metaphysically evil because it entails the going out of existence of the gazelle, this evil contributes to the good of the lion while the existence of the lion contributes to the order of the world.Footnote 56
Aquinas even mentions that (as counterintuitive as it may seem) a world in which God condemns a number of people to hell will communicate His goodness more than a world in which all rational beings went to heaven.Footnote 57 This is because God's goodness not only includes His love, but also His justice. Although God antecedently wills that all rational beings join Him in heaven, His justice demands that He consequently wills condemnation for those who do not follow His moral law.Footnote 58 So when God condemns unrepentant sinners as His justice demands, this demonstrates His goodness more than in a world in which no one were held accountable for unrepentance. Thus, God cannot be faulted for not creating a morally unsurpassable world. God is only logically required to produce the best order in any given world that He chooses to create. God's choice to create a world with a surpassable amount of happiness does not conflict with His perfection.
This leads to an important point regarding the perfect order of a world that God creates. It might be objected that it seems that a world with less evil would be a world with better ordering. If God needs to create a world with rational beings, then it seems that He should make a world where those beings do not die or face disease.
Aquinas famously believes that evil is a privation of the good.Footnote 59 Given his evil as privation theory and his position regarding God's purpose for creation, it is important to note that the presence of evil in the world would do nothing to disturb the order of creation. Indeed, Aquinas’ metaphysics entail that death and decay are to be expected in any contingent world. Contingent things, by nature, are corruptible. So God would need to supernaturally cause them to be incorruptible if He wanted them to last forever.Footnote 60 Because this is something that is not natural to contingent beings, it would be considered a grace if God were to cause contingent beings to become incorruptible.Footnote 61 However, He would not be obligated to bestow incorruptibility upon contingent beings, including humans.
Aquinas rejects the possibility of the existence of an actually infinite number of beings.Footnote 62 This means that any world God will create will be finite. Given this, there will always be a limited amount of resources in any world that God creates. A contingent world with limited resources entails the necessity of a natural order that is conducive to the subsistence of rational beings as a species, but will not guarantee the continued survival of individual rational beings.
Aquinas explains that
…since the good of the whole is better than the good of each part, the best maker is not he who diminishes the good of the whole in order to increase the goodness of some of the parts; a builder does not give the same relative value to the foundation that he gives to the roof, lest he ruin the house. Therefore, God, the maker of all things, would not make the whole universe the best of its kind, if He made all the parts equal, because many grades of goodness would then be lacking in the universe, and thus it would be imperfect.Footnote 63
A contingent world with limited resources would quickly degenerate if rational beings were exempt from the natural cycle of birth and death. Such a finite world would be quickly overpopulated and overtaxed. The perfection of the universe does not necessitate the continued existence of each individual rational being, but only the continued existence of the species of rational beings.Footnote 64
Conclusion
It is unfortunate that Aquinas has been misrepresented in the contemporary debate regarding best possible worlds. His natural theology has many good things to contribute to the theistic understanding of God's obligations and choices in creating. As shown, Aquinas should not be counted with Kraay's third category of positions if it is assumed that they all fall prey to the problem of no best world.
Aquinas’ philosophy entails that God is Infinite Goodness. God's infinite perfection entails that He is not obligated to will anything other than His own goodness and that God cannot create an infinitely perfect world. God's infinite goodness also provides a clue as to why He created, which is to communicate His goodness. So while God cannot create a best perfect world, He can create a perfectly ordered world. For any given world, God must create the best, but this only means that He must create a teleologically best world (given its quantity and quality of substances).
This shows that Ross is mistaken in claiming that Aquinas’ position is similar to Leibniz’. Aquinas’ concepts of God's freedom and God's perfection are compatible because God is not obligated to create an infinitely perfect world. He can choose to create any world He pleases as long as it is perfectly ordered to His goodness.
While Aquinas is a category (3) theist, he is not susceptible to the problem of no best world. God's perfection, according to Aquinas, does not entail that God must maximize the quantity and/or quality of goodness or happiness in the world He chooses to create. Instead, God intends to create a world that is perfectly ordered to His goodness. This means that worlds with higher quantities and qualities of goodness do no more to fulfill God's purpose and are not considered better. Thus, God's perfection is compatible with His choosing to create a world than which a greater can be conceived.
