Copyright © 1996 R.J. Kilcullen
To follow this lecture you will need either Readings or Thomas Aquinas, Summa theologiae, part 1 (also available on the web, English translation, Latin text); and either Supplement, or E. Gilson, History of Christian Philosophy in the Middle Ages.Thomas Aquinas was an Italian, a member of the Dominican order, who had begun his studies in Germany and came to study theology in Paris, during the middle ages the most famous centre of learning. He became Master of Theology in Paris under controversial circumstances. He was put into the chair during a time of controversy between mendicants and seculars, and the seculars at first put a ban on his lectures. You can read about this in James Weisheipl's book, Friar Thomas D'Aquino. He taught at various times in Paris, in Rome, in Viterbo and in Naples. Medieval academics moved around. His writings include a commentary on the Sentences of Peter Lombard, (every medieval theologian produced a commentary on Peter Lombard), commentaries on various books of the bible (English translations of his commentaries on Galatians and Ephesians are in our library), commentaries on various works of Aristotle (translations of some of them are in our library), and his most famous work, the Summa Theologica (more correctly called Summa theologiae). The term Summa means summary or abbreviation.
Open the Readings at p.101 (Summa theologiae, part 1). Read the Prologue.
Notice his criticism of the existing textbook in theology (i.e. Peter Lombard's Sentences) and lectures based on it: "multiplication of useless questions, articles and arguments", the unsuitable order in which questions arise, and repetitiveness. The Summa theologica was intended as a textbook to replace the existing textbook. It was not adopted; the Sentences of Peter Lombard continued to be the textbook throughout the middle ages. In the 16th century there was a revival of Thomas Aquinas's fame and influence and his book was sometimes used as a textbook for a while then.
One of his criticisms of lectures on the Sentences is that they take up questions in an unsuitable order. Order is one of Aquinas's main concerns in the Summa. The whole work is organised into three parts, part two being divided into the first part of part two ("prima secundae", I-II) and the second part of part 2 (secunda secundae, II-II). See the table of contents. Each part is divided into questions, each question into articles. At the beginning of each question there is a short prologue relating the question to the plan of the book and listing its articles. In Readings, p.101, RH side (Summa theologiae, part 1), read the top of the page, the prologue to Question 1. (Unfortunately the Web version of the Summa does not include the prologues to the various sub-sections of the work!)
Now turn to p.104, LH, and read the prologue to Question 2 (Summa theologiae, part 1).
Notice that these two prologues refer back to the purpose indicated in the prologue to the whole work, p.101, LH side. The prologue to q.2 sketches the organisation of the whole work. Part 1 of the Summa treats of God (his existence and attributes), part 2 of "the rational creature's movement towards God" (and in this part you will find a treatment of ethical topics), part 3 of "Christ who as man is our way to God" (Christ, the Church, the Sacraments). Notice the second line of this prologue, "as He [God] is the beginning of things and their last end"; this is an echo of the neo-Platonic theme of exodus and return - things proceed from God and then return (in the case of rational beings, by knowledge and love of their source); open Supplement, p.3; LH, read point (3), and p.4, RH side (Encyclopaedia Britannica, "Plato and Platonism"). The treatment in part 3 of Christ has no neo-Platonic precedent: the pagan neo-Platonists had no thought of a God-man as "the way" back to God. Reading on in the prologue to q.2 notice the successive stages or levels of division. After discussing the scope of the three parts of the Summa, he then (this is the second stage) subdivides the first division made at the first stage: "In treating of God there will be a threefold division" - these are the main divisions of Part 1. Then he again (third stage) subdivides the first of the second level subdivisions, again into three, and then (fourth stage) subdivides the first of the third level subdivisions, getting to the "three points of inquiry" that are the articles of this question. The subdivisions of the divisions not divided here will be explained when we get to them. Turn to Readings, p.107, RH, and read the prologue to question 3, which subdivides the second of the third-level subdivisions made in the prologue to question 2. In Readings, p.122 RH, the prologue to question 14 subdivides the third of the third-level subdivisions of the prologue to question 2.
Each prologue ends with a list of the articles to be dealt with in the question. The term "articles" just means parts that join together to make a whole - we still speak in this sense of "articulated" vehicles. "Question" means an inquiry or investigation. Each article begins with a question in the modern sense. E.g. article 1 begins with the question "Whether the Existence of God is Self-Evident?" Turn back now to Readings, p.101 (Summa theologiae, part 1), and read the first article of q.1.
Notice that the question is framed so as to ask for a "yes" or "no" answer. There are no questions like, "Why did God make a revelation to the human race?" A question like that can't be answered yes or no. Similarly there are no questions like, what is the definition of happiness? A question like that can't be answered yes or no. When he wants to discuss that topic, he asks "Whether Boethius' definition of happiness is correct?", which calls for an answer yes or no. (If the answer to such a definition question turns out to be No, he then asks whether some other definition is correct, until he arrives at one for which the answer is yes).
After the question calling for a yes or no answer there is an exchange of short arguments on either side of the question. He gives first the arguments he is going to reject. So in this first article objections 1 and 2 are arguments for a no answer, "on the contrary" introduces an argument for a yes answer. The term "objection" is a bit misleading. It meant originally something "thrown up", in this context an argument someone has thrown up or brought up in discussion, on either side of the question; so there are objections for as well as objections against. Turn to Readings, p.185, RH, top line, and notice the phrase "The arguments objected to the contrary" - i.e. on the side he has agreed with; this illustrates the use of "object" to cover arguments for. Return to p.102 (Summa theologiae, part 1, q. 1, art. 1).
After the objections for and against comes the heading "I answer that", which introduces Thomas Aquinas's answer to the question. And then comes the reply to the objections rejected.
Obviously you can't attribute to Thomas Aquinas himself the views expressed in the objections; he is committed to what follows "I answer that" - his answer, and his replies to objections. The conventional reference system cites part, question, article, and if necessary "ad" and the number of the objection ("ad" means "to", so "ad 1" means answer to objection 1). The last paragraph of the article you've just read is cited as "Summa theologica, 1, q.1, a.1, ad 2."
So what is the content of art. 1? Sacred doctrine is sacred teaching (that is what doctrina means). Why has God taught things to mankind in addition to what men can discover for themselves through philosophical reasoning? This is the question of Averroes' Decisive Treatise, and Averroes' answer is that God revealed himself in the Koran because he wanted to make sure that ordinary people would know what was needful for their salvation. Thomas Aquinas gives a similar answer. But notice that he also says that there are truths needed for salvation that philosophical reasoning could never attain: there are important truths human beings can't know unless God reveals them. Now read articles 2 and 10.
Read q.2, art.1, on p.104.
We looked at the reply to objection 2 when we were reading Anselm.
Read q.2, art.2.
The reply to objection 1 recapitulates what he said in q.1, a.1. The reply to objection 2 is important for article 3. Notice: "To take as a middle term the meaning of the name". In article 3 he will argue that there must be a first cause of all change. This implies that God must exist, because "first cause of all change" is part of what the name God means. So the final stage of the argument is: The first cause exists; God is the first cause; therefore God exists. This is a syllogism, AAA figure 1, with "First cause of all change" as middle term. Write the argument out and you'll see this. Similarly, when Anselm argued that that than which nothing greater can be thought really exists, this proved God's existence on the assumption that God is another name for that than which nothing greater can be thought.
Now read q.2 article 3, whether God exists.
These are famous arguments, the "five ways", about which much has been written. Let's not spend too much time on them now: you can come back and make a more detailed study later. So just a few points. When we were reading Anselm I suggested that you should be on the look out for words indicating logical structure - e.g. "therefore", which indicates that a conclusion is about to be drawn from premises just stated, and "for" which indicates that reasons, i.e. premises, are about to be given for a conclusion that has been stated first; "now" which often indicates the beginning of a stage of a multi-stage argument; and "but" which indicates a second premise. Go through the first way and underline such words.
About three quarters of the way through the argument notice "therefore" - "therefore, whatever is moved must be moved by another". This is the conclusion that was announced soon after the beginning of the argument, in line 3: "Now whatever is moved must be moved by another, for" - the passage from this "for" down to the "therefore" gives reasons for this intermediate conclusion, which becomes a premise in the last stage of the argument.
Go through the other "ways", now, and underline the words that indicate structure, and see if you can get a clear view of the structure of each argument.
Notice that each argument ends with something like "and this everyone understands to be God" - this is the meaning of the name God being used as middle term in the final stage of the argument, as foreshadowed in article 2, reply to objection 2, p.105 (Summa theologiae, part 1, q. 2, art. 2).
What are the main ideas in these five arguments? The first is about motion, which means every kind of change, not just local motion or change of place, but also ripening, heating, etc: there must always be a cause of any change, a "moving" cause. The second argument is very similar, about "efficient" causes. The difference between a "moving" cause and an "efficient" cause is that the moving cause produces the various stages through which changeable things pass, an efficient cause produces the existence of the thing in each of these stages, and the existence of unchanging things; the moving cause produces another state of something, the efficient cause produces existence. See Supplement, p.72 (Gilson, History of Christian Philosophy, p. 210-211). The ancestor of the first and second ways is Aristotle's argument in Physics book viii; turn back to Readings, p.90, R.H. side (van den Bergh, p. 261), and re-read Averroes' summary of this argument.
The third way is about possibility and necessity, and the key premise is that if something is possible then at some time that possibility must be realised; so if all things are such that their non-existence is possible, then at some time nothing will exist. This notion of "possible" as meaning "actual at some time or other" comes from Aristotle. It would seem that the third argument needs some patching. In a given finite period of time a possibility need not be realised: that my death is possible means, according to Aristotle, that it must happen sometime; but it hasn't happened yet. The third way seems to be a reductio ad absurdum: Suppose that there are only contingent beings, i.e. beings capable of ceasing to exist; and suppose this contingent universe has existed from eternity, i.e., that it has already existed through an infinite time. Then by now all possibilities must have occurred, including the simultaneous non-existence of everything.
The fourth argument, from grades of being, is Platonic; it should remind you of Anselm's argument in Monologion, chapter 4, Readings, p.22.
The fifth is like the argument from design, except that the evidence offered for the existence of an intelligence behind the universe is not the orderliness of the whole universe, but the apparently purposive activity of each and every part. Recall Aristotle's teleological view of nature, that a natural process is for the sake of some end. Aristotle's God did not appoint the ends, they just were! But Thomas Aquinas says that there can't be purposiveness without a guiding intelligence.
Let's leave these arguments and move on to question 3. Read the prologue and article 1.
An ambiguity in the first few lines after "I answer"; "no body moves unless it be moved" - take "moves" here transitively, i.e. as moving something else. No body makes another body move unless something makes it move. But God makes other things move without himself being moved - he is the first in the series of things moving things that move things. That there is a first mover was argued in the first way, in q.2. art 3. The arguments of the next few articles build on the arguments of the five ways. The translator's footnotes give you the back-references as the argument of the work develops; they are worth looking up.
Now read article 2, whether God is composed of matter and form.
To follow this argument you need to remember some of the points I explained in commenting on Averroes, Readings, p.90. Obviously, Thomas Aquinas is using the Aristotelian material that had come into Latin from Arabic and Greek in the twelfth century.
Read article 3.
The term suppositum refers to the individual as individual. "The nature or essence must differ from the suppositum" means that the individual is not his own nature or essence - Socrates is not his humanity. God, on the other hand, is his divinity, and is his goodness, and is his justice, and is identically whatever can truly be predicated of him. Re-read Anselm Monologion ch.16, Readings, p.24. Notice that according to Thomas Aquinas individual material things are individuated, i.e. distinguished from other individuals of the same species, by their matter, not by their form. Socrates and Plato do not differ in their humanity, but they are different bodies, differing by their matter-in-space. It is as if matter were the biscuit dough and the form is the cookie-cutter, stamping out different individuals all with the same shape but in different bits of dough. Different bits of matter are in different locations in space; individuals of the same species, however much they are alike in qualities and other accidents, can be distinguished by pointing. The word "this" suggests pointing.
Read article 4, on p.110 (Summa theologiae, part 1, q. 3).
In Aristotle, and in Boethius and other authors we read earlier, no distinction is drawn between essence and being. For Aristotle a human being's being is being human. But the Muslim philosophers noticed the need to distinguish between a human being's being human and his being; or, as we would find it more natural to say, between being human and existing. Turn to Supplement, p.59 (RH, second paragraph, from "No such thing"), and read to p.60 LH, then p.62 RH (Gilson, History, pp. 185-191).
Thomas Aquinas differs somewhat from Alfarabi and Avicenna in emphasising that since existence is fundamental to a thing it is unsuitable to say that existence is an accident. Re-read this article. Notice at the end the Platonic language of participation: a participated being is one that derives its being from Being itself, as, in Plato's theory, the many individuals are, for example, beautiful by sharing in Beauty itself. According to Thomas Aquinas God is Being itself.
Read article 5.
"The Commentator" (Objection 2) is Averroes. During the middle ages Aristotle's works in Latin translation were almost always accompanied by Averroes' commentary. Aristotle's text was divided into short blocks, each of which was followed by Averroes' commentary (as in The Incoherence of the Incoherence a passage from Ghazali is followed by a comment). So Averroes was the commentator, just as Aristotle was the Philosopher. Notice in the first reason given why God is not in a genus the premise that in God there is no potentiality; this premise has also figured in other articles in this question. It derives from the first way (p.106); the connection is made clear by Averroes in Readings, p.90, RH (van den Bergh, p. 261) - there is a substance which is "pure act". Compare Thomas Aquinas, Readings, p.108, LH, first 10 lines of the answer (Summa theologiae, part 1, q. 3, art. 1), and p.109, LH, the answer (Summa theologiae, part 1, q. 3, art. 2). To return to p.111 (q. 3, art. 5). "The Philosopher has shown that being cannot be a genus"; you should remember this from the tape on Porphyry's Introduction and Aristotle's Categories.
Read article 6.
Now read article 7, which sums up the conclusions of all the other articles of this question.
The absolute simplicity of the First was of course an important thesis of neo-Platonism.
Re-read on p.107 the prologue to Summa theologiae, part 1, q.3. Question on God's perfection and infinity we will omit, also on his unity; let's look at the question on his immutability. Turn to p.113 and read q.9, a.1.
Notice in reply to obj. 1 the distinction between change and action (or operation): For Plato immutability is an implication of full reality; yet in Plato's later philosophy souls are fully real, though they have life and activity: activity is not necessarily change (though in human beings activities begin because of some change - something affects our senses, and we thereupon take some action).
As I remarked earlier, the Summa theologica became a textbook in the 16th century. Various people produced commentaries on it. The most notable was Cardinal Cajetan. You may have heard of him in early modern European history; he was sent by the pope to Germany to meet Martin Luther and persuade him back into obedience to the Catholic Church. His mission was not a success. Anyway, he produced an influential commentary on the Summa theologica. In it he suggested that the five arguments for God's existence are not in fact completed until the end of question 11: by then enough attributes of the first being have been demonstrated for it to be possible to say "and this everyone understands to be God". On this view the claim "this everyone understands to be God" made at the end of each of the five ways in q.2 a.3 was premature. Cajetan's view has some plausibility. I doubt whether most people will recognise the first unmoved mover as God. They may also wonder whether the five arguments prove the existence of one and the same being. By the end of question 11 enough implications of these five arguments have been drawn out for it to be more credible that they are proofs of its existence of a single being with the attributes that philosophers traditionally ascribe to God. Some of these questions I have not included in the extracts; e.g. q.11 arts 3 & 4 argue that there is just one being with these attributes. So if you want to evaluate the five ways consider the chain of arguments up to the end of q.11. In Supplement, p.101, you will find some analysis of q.2 art. 3.
Before going further into the Summa theologica let's look again at Aristotle on potency and act, concepts which have figured prominently in the part of the Summa that we've read so far. Open the Supplement at p.99 and read that page.
The text of Parmenides was not available in Latin during the middle ages. Parmenides was a Greek philosopher a little earlier than Socrates. This passage comes from his philosophical poem. the first paragraph is taken to mean that non-entity, nothingness, is unthinkable: an object of thought must have some being. The next paragraph contains the key argument. How can anything come to be? Either from nonentity - but that is unthinkable - or from what is - but if it already is it cannot come to be. So nothing can come to be. If it is it always was. Or rather, not was but is - in the real there is no passage of time because there is no change. This is reminiscent of the God of later philosophers - ungenerated, eternal, unchanging. Parmenides it seems to be talking about a material body: reality must be like an indivisible sphere. Re-read the third paragraph. Parmenides' reality is like the atoms of Democritus and Epicurus, except that their atoms were many and moving: Parmenides' reality is like an atom in that it can't be cut or divided (which is what atom meant), but it is single and unmoving. This extract is from the way of truth or persuasion; in the second part of his poem Parmenides follows the way of appearance and tells us how things seem: the universe certainly does not seem to be an immovable indivisible sphere.
The basis of the argument of the way of truth is a sharp distinction between being and non-entity, and a univocal use of the term "being". Aristotle will later distinguish between simply being (i.e. existing) and being something (e.g. hot). With this distinction in mind let's run through Parmenides' key argument again. How can anything come to be - e.g. to be hot. Either from not-being, i.e., not being hot, and this is not unthinkable - not being hot is being cold, not absolute non-entity. Or from what is, i.e., what is hot; and of course if it is hot already it can't become hot. So it is the first alternative Aristotle takes: hot things come to be from what is not - i.e., from what is not hot. But then there must be something that is not hot but can become hot: so as well as distinguishing between being simply, i.e., existing, and being something, we need to distinguish between being actually something and being something potentially. So "being" is an equivocal term.
Re-read the extract from Plato's Sophist. Plato also saw the need to distinguish different ways of being and not-being, though he doesn't draw the same distinction as Aristotle.
Now turn to Supplement, p.114, and read Aristotle, Physics I.7 (or on the web at http://classics.mit.edu/Aristotle/physics.1.i.html, part 7).
You've read that chapter before. Now read the next chapter, 8, down to 191 a35.
He is referring to Parmenides, the passage we've just read. The Alexandrian neo-Platonist, Simplicius, in his commentary on Aristotle's Physics, quotes Parmenides at this point in his commentary, and that is how the text of Parmenides has come down to us, embedded in the commentary.
Read Aristotle's next paragraph, to 191 b9.
Let's suppose that a doctor learns to play the piano and becomes a musician. We can then say that a musician has come to be from a doctor: but not qua doctor, rather qua non-musician. (Qua means "in respect of being", or "in his capacity as". Qua student you do not have a right to vote in elections for parliament, but you do qua adult citizen.) So before he learns the instrument what is significant in this context about the doctor is not that he is a doctor but that he is not yet a musician. So the musical comes to be from the non-musical, the hot comes to be from the not hot; in general, things come to be, i.e., to be something, not from not being at all, but from not being that something - musical, hot etc.). For not being at all, "not-existing", Aristotle sometimes says "not being without qualification", i.e., without the addition of any qualifying word like "musical" or "hot".
Read the rest of chapter 8, and chapter 9.
In Aristotle's view what prevents Parmenides' inferences from being correct is that there are things which are not actually but are potentially this or that. But in the being in which there is no potentiality, the being that is pure act, all Parmenides' conclusions will hold, at least those that do not suppose that the fully actual being is a body, like a sphere (because a body contains matter, potentiality, the fully actual being can't be a body). So re-read the second paragraph of Parmenides, Supplement, p.99, and then turn over to p.100 and read "Parmenidean themes in Thomas Aquinas".
These 9 points Aristotle accepts, but Thomas Aquinas, like Avicenna, doesn't want to go right down the Parmenidean way. Following up the references I give on the RH side of p.100 should keep you happily occupied for a while. This is an outline of the research needed for the essay topic, "Does Thomas Aquinas succeed in reconciling God's immutability with the religious belief of Christians?"
Now turn to Readings, p.114, Summa theologiae, part 1, question 13, on the names of God. "Name" here means any descriptive word, including both nouns and adjectives, e.g. "The First", "good", "intellect", "will", etc. What do such words mean as applied to God? You will remember Averroes' view that in application to God our language is equivocal: words can't mean the same as applied to both God and creatures. This was a point strongly made by the neo-Platonists, who held that "the First" is beyond human understanding and beyond human language. See Supplement, p.3, points 6 and 7 (Encyclopaedia Britannica, "Plato and Platonism").
One of the transmitters of neo-Platonism to Latin Europe was Dionysios the pseudo-Areopagite. One of his works, translated by John Scottus Eriugena, was the De divinis nominibus, on the Names of God. You will find a brief account of it in Gilson, History of Christian Philosophy in the Middle Ages, pp.81-5. According to Dionysios, words describing God can be taken from the bible. There are three stages:
First, we affirm that God is what Scripture says he is: One, Lord, Powerful, Just etc.... [But] such notions cannot possibly apply to God in the same sense as to creatures: hence... the necessity of denying that God is any of those things in the only sense which we can give to those words... This second moment [or stage] constitutes what the theologians call the "negative theology". These first two moments are then reconciled in a third one, which consists in saying that God deserves these names in a sense which, because it is incomparably higher than that in which it applies to creatures, is inconceivable to human reason... God is "Hyper-being", "Hyper-goodness", "Hyper-Life" and so on. (Gilson, ibid., p.82).
In other words, we must say, "God is good - not as the things we know are good, but in some inconceivable superior way." We can't spell out the meaning of the third part of this statement, since God's superior way of being good is inconceivable to us. We can spell out the second part - we can say why God is not good as the things we know are good, e.g. because his goodness is not a quality distinct from himself which he could lose without ceasing to be himself. So we can say what God is not - or in what respect he is not the things he nevertheless is in an inconceivably superior way, but we can't spell out what he is, because we can't know him as he is in himself.
This doctrine of Dionysios has echoes in Thomas Aquinas. See for example in Readings, p.104, Summa theologiae, part 1, the prologue to q.2, toward the end: "Concerning the divine essence, we must consider... (2) the manner of his existence, or rather, what is not the manner of his existence"; this is a reference to Dionysios' negative theology. On p.107, prologue to q.3, second sentence: "Now because we cannot know what God is, but rather what he is not, we have no means of considering how God is, but rather how he is not.... Now it can be shown how God is not by removing from him [i.e. denying of him] whatever does not befit him - viz., composition, motion and the like". He goes on to explain the next few topics in a way that suggests that even the positive-sounding attributes, like simplicity, are really negative. Turn now to p.114, Summa theologiae, part 1, q. 13, art. 2. In art.1, which I have omitted from the Readings, he says that since we cannot in this life directly know God's essence (this was shown in q.12, also omitted), we therefore have no language capable of expressing the essence of God as he is in himself; however we can know him and speak of him as the cause of creatures. Read article 2.
The Rabbi Moses is Moses Maimonides, a medieval Jew whose writings were translated into Latin and influenced Thomas Aquinas on some important points: but here his view is rejected. The main point in this article is in the last 8 lines of the answer (between notes 11 and 12).
Read article 3.
Notice the distinction between what a word signifies and its mode of signification. For example, what the words "justice" and "truthfulness" signify is justice and truthfulness; their mode of signification is that they signify justice and truthfulness as qualities existing in a subject, each distinct from other qualities and from the subject.
Read article 4.
Note the contrast between multiplicity and unity. In creatures justice and truthfulness are different qualities; in God his justice is the same entity as his truthfulness, namely himself, though these words are not therefore synonyms.
Read article 5.
So words like "good" as applied to God and to creatures are not univocal, nor merely equivocal, but analogical. Notice that in this article both sets of objections, the objections for as well as the objections against, are answered.
Read article 6.
Notice at the end of the answer the terms "significance", "imposition", and "mode of signification"; the word, e.g., "justice" was imposed (or invented by human convention) to refer to something as it exists in creatures. This something, e.g. justice, is the significance, "as it exists in creatures" is the mode of signification (e.g. as a quality in a subject distinct from the subject and from other qualities). What is signified, justice, is also in God, but not as a quality distinct from the subject and from other qualities.
I'll leave it to you to read the rest of question 13. Turn to p.122, Summa theologiae, part 1, question 14, and read the prologue.
"One kind of operation is immanent, and another kind of operation proceeds to an exterior effect". Immanent means "remaining within", i.e. within the doer, as when you think of something. The other sort is, for example, when you pick something up - something outside yourself is affected; this sort of action is called transeunt meaning "going across" (to something else) (not transient, meaning soon gone). Question 14 includes some of the topics debated between Al Ghazali and Averroes.
Read article 1.
"The immateriality of a thing is the reason why it is cognitive"; Compare Averroes, Readings, p.91. 436.9-10 (van den Bergh, p. 262). Thomas Aquinas also seems to make the neo-Platonic assumption that matter is the only obstacle to thought, so that whatever is immaterial has knowledge. Compare the reply to objection 3 with Boethius, Consolation book 5, prose 4, copied in Readings, p.6, LH, three quarters of the way down.
Read article 5, p.124 RH.
Read article 6.
Read article 11.
These three articles (5, 6, 11) say that God knows things other than himself, i.e. creatures (art.5), and not only as beings but also as various genera and species of beings (art.6), and not only as genera and species but also as individuals (art.11). Thus Thomas agrees with Al Ghazali against Avicenna and Averroes (Incoherence of the Incoherence, 11th discussion, Readings, p.87 ff.(van den Bergh, p. 255 ff)). Notice that individuals are distinguished from one another not by a unique collection of forms (no collection of forms can be unrepeatable) but by matter; cf. Summa theologiae, part 1, q. 14, art. 11, p.127, LH, three quarters of the way down, "He who knows Socrates because he is white, or because he is the son of Sophroniscus, or because of something of that kind, would not know him insofar as he is this particular man". And in the same article, p.127, RH, top line, singular things "are individuated by matter". Since God is the cause of matter his knowledge extends to things as individuals.
Read article 13.
This is essentially Boethius' solution.
I'll leave it to you to read art.15, and question 15. Turn to question 19, and read to the end of article 2.
Notice in article 2 the idea that since God is good he will wish to spread his goodness by creating other things.
Read article 3.
Recall the distinction we first met with in Boethius between absolute and conditional or hypothetical necessity, or (as Thomas Aquinas calls it) necessity by supposition. Conditional, hypothetical or suppositional necessity is the necessity of inference - if the premises are true, then, necessarily, what they imply is true. "If the premises are true" - i.e., on condition that, on the hypothesis that, or on the supposition that, the premises are true, what they imply must be true. So if we suppose that it is true that Socrates is sitting, then, necessarily, Socrates must be sitting. But obviously this sort of necessity won't hinder him if he wants to stand up. God's willing things other than himself is not absolutely necessary - the universe does not proceed from him inevitably like light emanating from the sun.
Read to the end of article 6.
The answer to objection 1 is an attempt to reconcile the three propositions that God's will is always fulfilled, that he wills the salvation of all mankind, and that some will not be saved.
Read article 7.
God's will does not change. He wills with one unchanging act a schedule of things to happen at various times: what happens changes when the time comes, but God's will does not change.
Read article 8.
This is an attempt to reconcile the proposition that God wills everything that happens with the proposition that human beings act freely. The solution Thomas suggests is that God wills that we do some things freely. He wills not only that we do the thing, but also that we do it by choice, and his will is fulfilled. Bear in mind that Thomas Aquinas, like Boethius and Augustine, meant by a free act simply one that we choose to do: that does not rule out the possibility that something makes us choose. (More exactly: according to Thomas Aquinas an act is free if we choose it and if the choice is not determined by a necessity of nature, i.e. of human nature. If a choice is determined by a necessity of nature, then we will make it no matter what the circumstances, no matter what other causes or influences are operative. According to Thomas Aquinas choice is naturally necessitated only in the next life, in heaven; when we see God face to face, we cannot not love him. But human nature does not necessitate any other choice. His doctrine on freedom contrasts with that of Duns Scotus, who held that for a choice to be free we must be able to make the opposite choice even if all the circumstances, all things in the universe, remain the same. So Duns Scotus says: the choice is free only if we can choose the opposite all circumstances remaining the same. Thomas Aquinas says: the choice is free except when we would make it no matter what the circumstances.)
I'll leave you to read to the end of q.25 art. 6 (Readings, p.141). On p.140 you will find that Thomas Aquinas rejects Averroes' doctrine that God must produce the best possible world.
This completes the extracts in the Readings from the sections of Summa part 1 that deal with God himself. Go back to p.104, LH, and re-read the prologue to q.2. He says "In treating of God there will be a threefold division". The extracts we've read so far come from the first division. We omit the second division entirely ("the distinctions of Persons", i.e. of Father, Son and Holy Spirit, which concerns the doctrine of the Trinity). Shortly we will start reading extracts from the third, on the procession of creatures. The end of the section on God is an appropriate time to look again more carefully at the "five ways", on p.106 (Summa theologiae, part 1, q.2, art. 3). See Supplement, pp.101-2 for an analysis. Re-read the five ways, with that analysis.
Now let me make a few critical comments on the arguments.
First, notice that none of them proves that there is one and only one such being. For example, the first and second ways argue that a series of things causing things cannot go back to infinity, it must have a first: but there is no argument to show that there is only one such series. Perhaps each series of things causing things must go back to something uncaused, but maybe there are many unconnected series and many uncaused causes. Similarly the third argument does not exclude the possibility of several uncaused necessary beings, the fourth does not exclude the possibility of several things that are maxima in their respective genera (and remember that being is not a genus), and the fifth does not exclude the possibility that several intelligences assign ends to different natural processes. Further, there is no argument that the being whose existence is proved by the first way is identical with the beings whose existence is proved by each of the others. The Summa theologica is a book for beginners; Thomas Aquinas knew of arguments for some or all of these points (e.g. for the unity of the highest being) but did not include them in this article. However, they are needed to bring his proofs for God's existence to completion. Turn to Supplement, pp.72-3 (Gilson, History of Christian Philosophy in the Middle Ages, pp. 210-213; notice the last paragraph on p.72, and the last paragraph on p.73 LH: Avicenna was conscious of the need to show that the various orders have one and the same apex. In Supplement, p.78, LH (ibid., p. 222), notice the question "how many are there", and Averroes' answer.
Another criticism relates to the first and second ways. Notice in the first way toward the end the statement, "But this cannot go to infinity, because then there would be no first mover, and, consequently, no other mover, seeing that subsequent movers move only inasmuch as they are moved by the first mover". Objection: No, they move only inasmuch as they are moved by the preceding mover in the series. If the series is infinite there is no first mover, but for any given mover there is a preceding mover. Similarly, in the second way, note this stage of the argument: "Now to take away the cause is to take away the effect. Therefore, if there be no first cause... there will be no ultimate, nor any intermediate, cause. But if in efficient causes it is possible to go to infinity, there will be no first" etc. But not because any cause has been "taken away", so no effect will have been taken away, so all the intermediate causes, and the ultimate cause, will still be there.
The third way, as I observed earlier, seems to need patching. "Therefore, if everything can not-be, then at one time there was nothing in existence". Why "was"? Why not "will be"? The rest of the argument requires "was"; "even now there would be nothing in existence... if at one time nothing was in existence... even now nothing would be in existence - which is absurd". Gilson has suggested that the argument must assume that the universe has existed already for an infinite time: during an infinite time every possibility worthy of the name will at some time have been realised. On this interpretation the argument would run as follows. Suppose, first, that everything is contingent, and suppose, second, that the contingent world has existed an infinite time. Then during that infinite past time every possibility will have been realised, and at one time nothing will have existed - and therefore nothing will exist now, which is absurd: so it can't be true both that everything is contingent and that the contingent world has existed an infinite time, i.e., either not everything is contingent, or the contingent world has not always existed. If not everything is contingent, then something necessary exists; and if the contingent world has not always existed then, again, something necessary exists which brought the contingent world into existence. So either way there must be something that necessarily exists. (As I pointed out earlier, not necessarily just one thing - the negation of "All things are contingent" is "At least one thing is necessary".)
On this interpretation (of Etienne Gilson) the third way has some plausibility, but it is still open to objection. First, even from the supposition that the world has already existed an infinite time it does not follow that every possibility worthy of the name must by now have been realised--for example, your death is possible but has not yet happened. As long as there is some time still to come, something that has not so far happened may still be possible. Second, there is nothing to say that all the possible non-existences must have happened at the same time so that at some given time nothing existed. In fact, in Aristotle's philosophy the generation of one thing is the corruption of another and vice versa - i.e., if something that now exists ceases to exist (is corrupted), something else comes into existence (is generated) from it. Nothing just ceases to exist leaving nothing behind. If this is true of all contingent beings, or even just of some of them, then the simultaneous ceasing to exist of all contingent beings is not possible no matter how much time elapses.
To the fourth way it can be objected that it is not true that "more" and "less" are always said of different things according as they approximate to what is greatest. In signed integers there is no greatest number, and no least number, but we can say that some are greater and some are less. Further, the expressions "according as they resemble" and "according as it more nearly resembles" imply that there are degrees of resemblance: the hotter things more nearly resemble the hottest, and that is why they are hotter. Then why are they said to be more nearly similar? Does this presuppose comparison with the highest degree of similarity? This is an argument of the "third man" type, and it seems to show that the premise that more and less are always said by approximation to a greatest implies an impossible infinite regress. It therefore can't be true that every comparison presupposes comparison with a maximum.
To the fifth way the objection is that if, as the first sentence says, we see that things which lack knowledge act for an end, and we don't see anything directing them to the end, then it does not seem true that "whatever lacks knowledge cannot move towards an end unless it be directed". We see arrows being aimed, but we don't know from experience that all natural processes are directed by an intelligence. Do we know otherwise than by experience - is there some argument to show that there must be a director even when we can't see one?
Objections against an argument need never be the last word. Someone may modify the argument, patch it in some way, or produce a counter to the objection. There is a considerable literature on the Five Ways, which you can find by means of The Philosophers Index. Hume's Dialogues Concerning Natural Religion (here or here) is a thorough criticism of the argument from design, which is akin to the fifth way. The first and second ways are sometimes referred to in the literature as the cosmological argument, which is Immanuel Kant's term. So here is a research topic if you want to pursue it.
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