In this article I present Aquinas's 5 ways in their logical structure and provide some discussion of the contentious premises or inferences.

This chapter contains sections titled: The First Way – The Argument from Motion The Second Way – The Argument from Causation The Third Way – The Argument from Possibility and Necessity The Fourth Way – The Argument from Gradation The Fifth Way – The Argument from the Governance.

Henry, his parents, and his dog Mudge take a vacation out West, where they enjoy tumbleweeds, desert animals, souvenirs, and the wide open spaces.

This paper will argue that the order and the unity of St. Thomas Aquinas’s five ways can be elucidated through a consideration of St. Thomas’s appropriation of an Avicennian insight that he used to order and unify the wisdom of the Aristotelian and Abrahamic philosophical traditions towards the existence of God. I will begin with a central aporia from Aristotle’s Metaphysics. Aristotle says that the science of first philosophy has three different theoretical vectors: ontology, aitiology, and theology. But (...) how can all three be united into a single Aristotelian science? In his Metaphysics of the Healing, Avicenna resolved the impasse by taking the ontological vector as the subject of metaphysics. He then integrated the question of the four first causes into the penultimate stage of his demonstration for the existence of God, thereby placing aitiological and theological questions among the ultimate concerns of a unified Aristotelian metaphysics. In the five ways, St. Thomas integrated Avicenna’s Aristotelian search for the first four causes into the last four of his five ways, by showing that each of the four aitiological orders terminate in an ultimate first cause that we call God. Finally, by appending the proof from the Physics to the beginning of the five ways, St. Thomas was able to show that the ultimate aim of both natural philosophy and metaphysics is the divine first principle, which is the beginning and subject of sacra doctrina. (shrink)

Reflecting on the knowledge of God in the Old and the New Covenant offers us anew way to address the theological status of the philosophical proofs for theexistence of God. In the treatise De Deo Uno of the Summa, Aquinas discusseshow the intellect experiences its natural capacity to know God. The “five ways”are inseparable from one another. In the prologue to the Lectura on Saint John,Aquinas‟s last Gospel commentary, the Doctor Angelicus praises the depth of theevangelist‟s contemplation by (...) comparison with pagan philosophical knowledgeof God, relating it to Isaiah‟s vision of God in the Temple in Jerusalem .“I saw the Lord on an elevated throne” . . . . Saint John‟s vision focuseson the authority and power of the Word: “I saw the Lord,” on hiseternity: “the Lord was seated;” on the excellence and nobility of hisnature: “I saw the Lord seated on a throne;” on his incomprehensibletruth: “an elevated throne.”2Bringing to light the unity of the knowledge of God in the Old and the NewCovenant, Aquinas continues: “It is through these ideas that the ancientphilosophies rose to knowledge of God.” Thus pagan philosophies becomeconnected with the Evangelist and with the Prophets. Indeed one can recognize inthe fourfold articulation of the contemplation of the Prophet and the Evangelistthe central axis of the “four ways” by which “several philosophies arrived atknowledge of God;” God as the intelligence governing nature ; as theunchangeable principle of all motion ; as supreme cause of being; as intelligence and infinite truth . Aquinas briefly developseach of these ways and concludes with a line of Scripture taken from Isaiah, apsalm, or the New Testament. He then adds: “Such was the contemplation of John who because he had seen the Word in its regulatory authority, its eternity,its excellence, and its incomprehensibility, wanted in his Gospel to transmit to ussomething about his contemplation.”3Here, unlike in the commentary on Hebrews 11: 6,4where Aquinasaccents the difference between philosophical knowledge of God and faith,Aquinas emphasizes the unity of the motion of the intellect seeking God, whetherit is philosophical or theological. These two ways of emphasis do not contradicteach other. The natural knowledge which a human being has of God receivesconfirmation and fulfilment in the revelation given to the prophets and to theapostles in the Old and the New Covenant. The fulfilment of the knowledge ofGod by philosophers transforms their “proofs” of God‟s existence by witnessingto the motion by which the human intellect is naturally drawn toward God itscreator. For natural knowledge of God, the intellect leads itself to the conclusions and, in a certain way, “walks forward” to encounter faith. Divine revelation transforms the “proofs” into “ways” toHim, who in reality manifests Himself by drawing to Himself the intellectthrough the infinite action by which he creates it. This natural motion is soimportant for Aquinas that in the prologue he suggests that the readers of hisbiblical commentary verify it for themselves. May we not consider that the “fiveways” of Question 2 of the Summa Theologica, the hinge between the definitionof sacra doctrina and the treatise De Deo Uno, play a similar role of theologicalself-verification? (shrink)

First published in 2003. Routledge is an imprint of Taylor & Francis, an informa company.

First published in 2003. Routledge is an imprint of Taylor & Francis, an informa company.

FIVE 'WAYS' TO PROVE THAT GOD EXISTS ARE OFFERED IN AQUINAS' "SUMMA OF THEOLOGY," ALL TAKEN FROM HISTORICALLY TRACEABLE SOURCES IN WHICH THEY DID NOT REACH THE CONCLUSION ENVISAGED BY HIM. 'WAYS' UP TO ELEVEN IN NUMBER ARE IN FACT USED IN HIS WORKS. ALL FUNCTION IN A STRICTLY METAPHYSICAL--NOT COSMOLOGICAL OR TELEOLOGICAL--FRAMEWORK THAT WAS DEVELOPED EARLY IN HIS CAREER. THE ANSELMIAN AND OTHER ARGUMENTS THAT CANNOT FIT INTO THAT FRAMEWORK ARE REJECTED OR LEFT UNNOTICED, WHILE THOSE (...) THAT DO FIT IN ARE ACCEPTED IN LINE WITH THE CONVENIENCE OF THE MOMENT. ACCORDINGLY THE NUMBER AND ORDER OF THE 'FIVE WAYS' MEAN NO MORE THAN A MOMENTARY CONVENIENCE OF THIS TYPE. (shrink)

Some will wonder why this book was ever written, thinking perhaps that there is nothing more to be said about "proofs" for the existence of God. Others of a more traditional inclination might be surprised at some of the conclusions drawn by the author. Kenny carefully scrutinizes the five ways of St. Thomas and concludes that they do not constitute rational proofs for God's existence. Kenny's chief criticism is that the arguments of Aquinas are too closely wedded to (...) a cosmology that cannot stand up under a modern critique. The value of this book rests precisely in its use of contemporary philosophy in evaluating the five ways. Perhaps the author's most serious criticism is directed against the Thomistic concept of esse and the notion of God as ipsum esse subsistens. These metaphysical notions of Aquinas have long been acclaimed as extensions of Aristotelian thought. Kenny, however, claims that they are Platonic in nature and hence subject to the centuries of criticism leveled against Plato's Ideas. Under a logical analysis, the notion of God as ipsum esse subsistens "turns out to be the Platonic Idea of a predicate which is at best uninformative and at worst unintelligible."--J. J. R. (shrink)

Without doubt, St Thomas Aquinas was the greatest of the medieval philosophers. Aquinas was a prolific writer and he made contributions to virtually every area of Philosophy and Theology. His account of the existence of God is perhaps the best known aspect of his work. This is especially true of the celebrated five arguments he adduced in demonstration of the existence of God. In exploring Aquinas’ Five ways, which some commentators regard as Aquinas’ substantive contribution to Philosophy (...) of religion, our contention is that they demonstrate the possibilities as well as the limits of natural theology, so far as while Aquinas does not deny that natural reason can establish the existence of God he nonetheless maintains that there are aspects of God’s nature that can be known only through the means of divine revelation. Consequently unless we take into account the double emphasis on the possibilities and limits of natural theology, we are sure underestimate the contemporary relevance of Aquinas’ Five ways. -/- . (shrink)

I present and evaluate the 5 Ways of St. Thomas Aquinas. I discuss the contentious premises and inferences of the arguments.

‘The Five Ways’ has been used as a translation of the phrase quinque viae which is used by Aquinas in Summa Theologiae I, 2, 3. I have put it in inverted commas because I think that it is a poor translation of the Latin. Aquinas’s use of the word via is sufficiently rich to confront us with a choice of English equivalents. There is no reason why in this context we should opt for ‘way’. Since we are not (...) being invited in ST I, 2, 3 on any journey in space, the initial presumption must be that ‘way’ should be used only if we fail to turn up anything more fitting. However, there is no difficulty in providing a more suitable English equivalent. Via is used by Aquinas in the sense of ‘a method of arguing’ or, more specifically, as designating particular arguments. When he considers the two viae by which Aristotle arrived at a certain conclusion, Aquinas clearly distinguishes an argument based on Physics VII from that based on Physics VIII. And in the same context Aquinas uses rationes as an equivalent of viae. Ratio is frequently used by Aquinas in the sense of the English word ‘argument’, as, for instance, in ST I, 30, 2 or ST III, 55, 5. Hence it seems to me that quinque viae should be translated as ‘five arguments’. (shrink)

The aim of the book is to show that the ’five ways’ of Thomas Aquinas, i.e., his five arguments to prove the existence of God, are logically correct arguments by the standards of modern predicate logic. In the first chapter this is done by commenting on the two preliminary articles preceding the five ways in which Thomas Aquinas points out that on the one hand the existence of God is not self-evident to us and on (...) the other hand, that, similar as in some scientific explanations, the mere existence of a cause for an effect which is evidently known to us can be proved. In the second chapter every argument is translated into the symbolic form of predicate logic and its logical validity is shown. Additionally a detailed and critical discussion of the premises of each argument is given. (publisher). (shrink)

The aim of the book is to show that the Five Ways of Thomas Aquinas, i.e. his five arguments to prove the existence of God, are logically correct arguments by the standards of modern Predicate Logic. In the first chapter this is done by commenting on the two preliminary articles preceeding the Five Ways in which Thomas Aquinas points out that on the one hand the existence of God is not self-evident to us and on (...) the other hand, that, similar as in some scientific explanations, the mere existence of a cause for an effect which is evidently known to us can be proved. In the second chapter every argument is translated into the symbolic form of Predicate Logic and its logical validity is shown. Additionally a detailed and critical discussion of the premises of each argument is given. (shrink)

The Third Way is the most interesting and insightful of Aquinas' five arguments for the existence of God, even though it is invalid and has some false premises. With the help of a somewhat weak modal logic, however, the Third Way can be transformed into a argument which is certainly valid and plausibly sound. Much of what Aquinas asserted in the Third Way is possibly true even if it is not actually true. Instead of assuming, for example, that things (...) which are contingent fail to exist at some time, we need only assume that contingent things possibly fail to exist at some time. Likewise, we can replace the assumption that if all things fail to exist at some time then there is a time when nothing exists, with the corresponding assumption that if all things possibly fail to exist at some time then possibly there is a time when nothing exists. These and other similar replacements suffice to produce a cogent cosmological argument. (shrink)

A number of recent discussions of atheism allude to cosmological arguments in support of theism. The five ways of Aquinas are classic instances, offered as rational justification for theistic belief. However, the five ways receive short shrift. They are curtly dismissed as vacuous, arbitrary, and even insulting to reason. I contend that the atheistic critique of the Thomistic five ways, and similarly formulated cosmological arguments, argues at cross purposes because it misrepresents them. I first (...) lay out the context, intent and structure of Aquinas’ arguments, then show in what way recent discussions misrepresent them, and finally conclude with a comment on metaphysical orientation, which I take to be central, not only to a proper understanding of the Thomistic five ways but generally to the debate between atheism and theism on the existence of God. (shrink)

This slender volume is a polemical work on two fronts. First and foremost, it is an attempt to distinguish sharply the aim of Aquinas from that of post-Cartesian rationalism with respect to the role of philosophical argumentation in establishing the existence of God. Cartesian rationalism holds that it is possible to articulate presuppositionless, universal, compelling, and purely philosophical reasons to justify a foundational belief in God. Velecky criticizes this view on Wittgensteinian grounds and holds that there are significant affinities between (...) Aquinas and Wittgenstein on the relationship between religious belief and philosophical justification. What counts as a good philosophical case for the existence of God is always relative to the existential situation of the inquirer. So-called proofs for the existence of God are really attempts to formulate corroborating intellectual grounds for a belief that one has already come to on the basis of God's self-revelation, faith, and personal encounter. Belief in the proposition "that God exists" is not a statement reporting the existence of an item encounterable in our normal experience or the conclusion of an argument, but rather expresses the adoption of an entirely distinct perspective on the whole of reality. So when Aquinas describes arguments for the existence of God as preambula fidei, he does not mean that they are prior to faith as epistemologically necessary conditions for belief, but rather that they are logically required by faith in a different sense. It must be possible to locate or refer to the object of religious belief within a universe of philosophical discourse; or, to put it another way, it must be possible to give some content to the notion of divinity. The function of Aquinas's arguments is thus to make the proposition Deum esse intelligible within the universe of broadly Aristotelian discourse. This is especially important if believers want to have any kind of conversation with nonbelievers. Velecky writes: "At the conclusion of the Five Arguments nothing more--and nothing less--has been achieved than that a reasonable philosophical case has been made for a topic of conversation between Christians and others about the basic characterization of something which is thought to be the transcendent cause of all beings and which has left some traces of its transcendence in the world we can experience". Velecky's Wittgensteinian reading of Aquinas is a welcome antidote to the more usual Cartesian reading. But while Velecky is careful to distinguish Aquinas from Wittgensteinian fideism, nevertheless his overall strategy comes dangerously close to pushing Aquinas too far in that direction; Aquinas is neither Cartesian nor Wittgensteinian. (shrink)

The “existential inertia” thesis holds that, once in existence, the natural world tends to remain in existence without need of a divine conserving cause. Critics of the doctrine of divine conservation often allege that its defenders have not provided arguments in favor of it and against the rival doctrine of existential inertia. But in fact, when properly understood, the traditional theistic arguments summed up in Aquinas’s Five Ways can themselves be seen to be (or at least to imply) (...) arguments against existential inertia and in favor of divine conservation. Moreover, they are challenging arguments, to which defenders of the existential inertia thesis have yet seriously to respond. (shrink)

Anthony Kenny criticized the Five Ways, by Thomas Aquinas, in a widespread and influential book. About the First Way, among other critiques, Kenny considers that Thomas Aquinas failed to prove that “whatever is in motion is put in motion by another”. As this principle is central for the argument developed by Aquinas on the “first mover, put in movement by no other”, the First Way is insufficient and grounded on a mistake. In this article, Aristotle’s and Aquinas’s works (...) are analysed to expose that their arguments about movement are sound and persuasive. On the contrary, Kenny’s criticism is not consistent and is misled by bad interpretation of texts and concepts. Oderberg and Weisheipl agree with Aquinas and Aristotle, and their papers reinforce the conclusions of this article, favourable to the Medieval philosopher and against Kenny. (shrink)

Considered one of the leading proponents of natural theology in the 20th century, E. L. Mascall (1905–1993) taught philosophy and theology at King’s College London for most of his career. Unlike many of his contemporaries, he insisted that classical theism, embodied in the writings of Augustine and Thomas Aquinas, could be successfully revived for a modern audience. Known for his vigorous defense of neo-Thomism, Mascall offered an unusual interpretation of The Five Ways. While modern scholastics typically read the (...) proofs as syllogistic exercises, Mascall maintained that God’s existence could not be deduced from premises, but must be grasped by means of a unique type of “metaphysical intuition” which he called “contuition.” In my paper, I will re-examine his position, explore his reasons for adopting it, and finally raise several questions concerning its significance for the history of neo-Thomism. (shrink)

My article critically evaluates five key claims in Kerr’s interpretation of Aquinas’s De Ente et Essentia, ch. 4, proof for God. The claims are: the absolutely considered essence is a second intention, or cognitional being; à la John Wippel, the real distinction between essence and existence is known before the proof; contra David Twetten, Aristotelian form is not self-actuating and so requires actus essendi; the De Ente proof for God uses the Principle of Sufficient Reason; an infinite regress must (...) be eliminated before concluding to God. This author wonders if these questionable claims are traceable to the mindset of analytic philosophy which values precision and discreteness and so can fail to appreciate crucial paradoxes in Aquinas’s metaphysics. (shrink)

The six articles that comprise Book 2, Distinction 1, Question 1 of Aquinas' Writings on the "Sentences" of Peter Lombard represent his earliest and most succinct account of creation. These texts contain the essential Thomistic doctrines on the subject, and are here translated into English for the first time, along with an introduction and analysis. In Article One Aquinas argues, against Manichean dualism, that there is one ultimate cause of all created being; in so doing he gives three proofs for (...) the existence of the Creator and the essential features of his answer to the problem of evil. Thomas establishes his definition of creation in Article Two, providing the needed distinctions between philosophical and theological senses of creation. Emanationism and the problem of whether there can be any intermediary causes in God's act of creation are the subject of Article Three. The next article demonstrates that although God is the cause of all created being, nevertheless creatures are true causes in nature. Article Five argues that it is from revelation alone that we know that the world had a temporal beginning, and that the philosophical arguments that purport to show either the necessity or impossibility of the temporal beginning are not persuasive. A detailed exposition of the meaning of the first sentence of the Bible, "In the beginning God created the heavens and the earth," follows in Article Six. (shrink)

The third volume of newly translated selections from the writings of Saint Thomas Aquinas, Fr. Richard Regan turns to his thoughts on the moral dimensions of human action. Focusing on the first part of the second folume of the Summa Theologiae, he deals with such topics as the ultimate human goal, human acts, emotions and virtues. Regan indicates that though Aquinas approaches these topics from the perspective of human reason, it is necessary for the reader to remember that his overall (...) viewpoint is that of a believer seeking to understand his faith. All can weigh the merits of these propositions due to their clarity of language, exposition, and structure. (shrink)

Why do we have obligations to the community to which we happen to belong? For communitarians, membership does more than provide the context for asking this question. In fact, the simple fact of membership goes some way towards justifying our obligations. According to the strong version of the communitarian thesis, membership is the fundamental consideration justifying political obligation; but for the weaker version, membership is one consideration among others and at times may be the less weighty one. John Horton's theory (...) of associative obligations can be read as moving back and forth between strong and weak communitarianism. His communitarianism is strong when he rejects value pluralism, arguing that one consideration, membership, is fundamental. However, Horton also advances claims that are compatible with not only the weak version of the communitarian thesis but also value pluralism. They suggest that, if membership is one reason among others to justify obligations, it is not fundamental as it can be defeated by other considerations. (shrink)

This paper distinguishes two ways in which to think about the freedom of extremists. Non-pluralists claim to have identified the general rule for resolving moral conflicts, and conceptualize freedom as liberty of action in accordance with that rule. It follows, if extremist violence breaks the rule in question, removing this option does not infringe the freedom of extremists. In contrast, for pluralists there is no one general rule to resolve moral conflicts, and freedom is simply the absence of interference. (...) I argue here that pluralism provides a principled defense of freedom, as it allows us to see that removing options from extremists is worse, on prima facie grounds, than not doing so. Also, non-pluralists cannot show that they have identified the general rule for resolving moral conflicts, and in particular, are forced to rely on quite different principles altogether when justifying paternalistic responses to extremism. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:What Makes the Common Good Common?Key Points from Charles De Koninck1Aquinas Guilbeau, O.P.In even the most capable philosophical hands, the common good remains a slippery concept. Its essence eludes the grasp of those who reach for it. This is due in part to the concept's complexity. "Common good" is composed of two rich, philosophically pregnant notions: goodness and commonness. Reflection on these two notions is ancient, of course. How (...) a thing is good has preoccupied philosophers since the dawn of time. How a thing may be common has exercised philosophers less throughout history, but even the ancients recognized that the question of a thing's commonness remains as intricate as the question of a thing's goodness. Despite their long philosophical history, however, the notions of goodness and commonness evade quick and easy description. Because they represent elemental characteristics of being itself, they share in being's fundamental mystery. As a result, millennia of reflection have not exhausted these notions' meanings. Like being, goodness and commonness require careful study by each generation, so that its intellectuals and teachers might clarify these notions' remaining secrets. Thus does each generation contribute to the perennial philosophy.When we modern and post-modern thinkers try to describe the common good, and thereby grapple with its notions of goodness and commonness, we find one of these two notions more elusive than the other. Which of the two might surprise us. It is not the common good's goodness. [End Page 739] Despite the philosophical confusions of our age, we more or less still agree publicly as to what constitutes a good, and as a result what constitutes an evil. We deem health a good, for example, while we deem disease an evil. We embrace one as perfective; we repulse the other as destructive. To my knowledge, no one has yet extolled COVID-19 as a good. So, we moderns and post-moderns have not completely lost hold of reality. We still share a sense of goodness, even if our generation mislabels some evils as goods.When it comes to describing the common good, therefore, it is not the common good's goodness that eludes us. Rather, it is its commonness that we have difficulty grasping. What does it mean for a good to be common? How is a common good common? Are all common goods common in the same way? How is the example of health common? Is health a common good properly speaking, or does it only appear to be common? How do we know the difference? Is there a difference? Unfortunately, few of us can answer these questions well. The reasons may not all be our fault, but we should admit that, along with our secular contemporaries, we remain largely unversed in commonness. A sign of our inexperience with the concept is that we seldom ask questions about commonness. Instead, we take it for granted that we know what commonness involves. When pressed to describe it, however, we quickly discover just how uncommon understanding of commonness is.In the first half of the last century, Charles De Koninck was well aware of modernity's inexperience with commonness. He recognized that individualism and its philosophical prerequisites had so captured the popular imagination, even among Catholics, that the common quality of the common good was disappearing from view. As a result, political discourse—to say nothing of political life—had entered serious difficulty. Between the World Wars, De Koninck spoke up among Catholic philosophers to remind them of the "primacy of the common good," not simply as a practical concept but as a speculative one, in accord with its classical conception.De Koninck recalled for his contemporaries not only that but also how commonness, like goodness, is primarily something objectively real and metaphysically constituted, and only secondarily something subjectively perceived and practically useful. To revive the objective and metaphysical notions of goodness and commonness among Catholic intellectuals—many of whom had traded these for easier subjective and practical notions2—De [End Page 740] Koninck composed his famous essay The Primacy of the Common Good, Against the Personalists.3 In it, De Koninck spends eighty pages reviewing the objective... (shrink)

For Thomas Aquinas, the Book of Job is the authoritative teaching concerning divine providence. In his Literal Exposition on Job, Aquinas offers a line-by-line commentary on the scriptural text. He analyzes the text not only by way of cross-references within the Book of Job and to other parts of Scripture, but also by appeal to the writings of Aristotle, the Church Fathers, and other Christian Aristotelians. Anthony Damico's translation is more literal than literary, preferring to render the Latin words wherever (...) possible by their obvious English derivatives. Martin Yaffe provides an extensive interpretive essay, bibliography, and indexes of citations. (shrink)

Aquinas’s Five Ways are not to be understood as demonstrative proofs, successful or not, for the existence of God. Rather, they provide a necessary step towards supplying licensable surrogates for the essential predications that cannot logically be drawn from the incomprehensible nature of God, yet would seem needed for the Summa’s declared genre of argued theology. (Predication secundum analogiam provides surrogates for non-relational accidental predications, likewise unavailable.) What Aquinas is proving in arguing deum esse in ST I.2.3 is (...) not God’s actual existence (see ST I.3.4 ad 2) but an alternative interpretation of “God’s being something” where “God is something” is a placeholder for, say, “God is prime mover” or, more explicitly, for such (necessary) identities as “The prime mover is the necessitated necessitator,” an identity whose necessity depends at more than one place on the assumption of God’s existence from faith, not on demonstrative proof of God’s existence. (shrink)

Attitudes towards the fourth way differ from incredulity and embarrassment to seeing it as a profound demonstration of God’s existence. Aside from general treatments on all the five ways, the fourth way has received little by way of direct commentary in comparison to the other better known (and arguably better appreciated) ways. In this article I seek to present Aquinas’s fourth way as a way to God which makes use of his general and more familiar metaphysical reasoning. (...) This serves to give the reading of the fourth way as a profound argument for God’s existence, and also to integrate it with the other four ways given the common metaphysical backdrop. (shrink)

Thomas Aquinas wrote a text later known as Quaestio de attributis and ordered it inserted in a precise location of his Commentary on the Sentences of Peter Lombard more than a decade after composing this work. Aquinas assigned exceptional importance to this text, in which he confronts the debate on the issue of the divine attributes that swept the most important centres of learning in 13th Century Europe and examines the answers given to the problem by the representatives of the (...) four mainstream schools of his time: the Greek mystic Dionysius Areopagita, the Latin Saint Anselm of Canterbury, the Jewish rabbi Moses Maimonides and the Muslim philosopher Ibn Sina. This in-depth study of Thomas Aquinas’ Quaestio de attributis (In I Sent., d. 2, q. 1, a. 3) binds together the findings of previous research on the unique history of this text by reconstructing the historical circumstances surrounding its composition, shows that the Quaestio contains Aquinas’ final answer to the dispute on the divine attributes, and thoroughly examines his interpretation of Maimonides’ position on the issue of the knowledge of God by analysing this and other texts related to it chronologically and doctrinally. The examination of the Quaestio reveals the background of Thomas Aquinas’ renewed interest in Maimonides’ position on the issue and brings to light elements of Aquinas’ interpretation that are absent from his earlier references to Maimonides. Moreover, the chronological and doctrinal connection of the Quaestio de attributis to other Thomistic works with explicit references to Maimonides enables a reconstruction of his comprehensive approach to Maimonides’ teaching on the possibility and extent of the knowledge of God in the Guide of the Perplexed and highlights the place of Maimonides’ philosophical teachings in Thomas’ own thought in issues like "Being" as the proper name of God, the multiplicity of the divine names, the beatific vision in the afterlife, the causes that prevent the instruction of the multitude in divine matters and the role of faith and prophecy in the acquisition of the true knowledge of God in this life. The last chapter examines the reasons behind Aquinas’ silencing of Maimonides’ name when introducing his Five Ways for the knowledge of the existence of God, in spite of the evident relation between these and Maimonides’ Four Speculations. The study is completed with an extensive appendix that includes the text of the Quaestio de attributis with an English translation and the critical edition of several chapters of the 13th Century Latin translation of the Guide of the Perplexed known as Dux neutrorum. (shrink)

In the Third of his celebrated Five Ways in Summa Theologiae Ia, q. 2, a. 3, St. Thomas Aquinas argues for the existence of God from contingency and necessity noting that the world contains possible beings which are able not to be since, being generated and corrupted, they at some time do not exist. He claims to show that there must be some necessary being since it is impossible that all things are possible beings. Scholars have long found (...) this part of the Third Way problematic, since it appears that Aquinas is committing a logical fallacy. He seems to be arguing that all members of a group have one common attribute since they each have their own particular instance of that attribute, as one might argue that since everybody has a birthday, i.e., one day on which each was born, therefore, there is one (and the same) day on which everyone was born. This paper will show that the accusation that Aquinas commits the alleged Birthday Fallacy would mean he was arguing for a temporal beginning for all material things, and so believed that such claim was philosophically demonstrable. Aquinas, however, argued against our ability to naturally know physical creation had a beginning in time; such knowledge requires God’s revelation of it. Instead Aquinas in the Third Way is allowing for the possibility that the physical universe could be temporally infinite, as Aristotle argued, but that this possibility would still support Aquinas’ contention that some necessary being must exist. (shrink)

At present a broad consensus may be discerned on Aquinas' ‘five ways' for proving the existence of God: either he is responding to atheism per se by means of five rational arguments, or he is not responding to any formal denial of God's existence. Both of these approaches ignore the two specific objections Aquinas raises prior to the five ways: evil is incompatible with the existence of an infinite goodness , and the world does not (...) require an external explanation . While some have speculated on the structural significance of the second objection, the first has been universally regarded as irrelevant. This, I argue, is an oversight; Aquinas' first objection is central to the quinque viae. Seen in this light, while Aquinas' five ways are not responses to atheism per se, they do address, and ultimately subvert, a specific form of disbelief. (shrink)