Copyright © 1996 R.J. Kilcullen
This lecture is concerned with Averroes' Tahafut-al-Tahafut, thirteenth discussion. Turn to Readings, p.95 (or van den Bergh, p. 275; online version here). To follow it you will need either the Supplement, or
Read the heading. Recall Boethius' view (here) on the problem of divine foreknowledge and human freedom, that God does not fore-know, since all his knowledge is present. The philosophers Ghazali criticises also hold that God's knowledge does not change; but they infer from this (as Boethius did not) that therefore God cannot know passing events. Ghazali agrees that God's knowledge never changes, but wants to hold, as a religious person must, that God does know passing events and changing individuals. Read to the end of the paragraph at 457.3 or thereabouts.
This is pretty clear: according to these philosophers God knows all about eclipses in general terms, but does not know that an eclipse is happening now, or that it has finished.
Read to 458.3.
Again, according to the philosophers God knows all about human beings in general, but not about the various doings of Zaid in particular, because the identification of an individual requires sense-perception and pointing, and this requires a body, which God does not have.
The first paragraph, down to 458.10, is repetition. Then comes a threefold distinction, which amounts to this, that a change in the relation of things to me need not be a change in me: if something moves from my right to my left it changes position, but I do not change. However, the philosophers say, knowledge of changing things is not like this, a mere change in external relations. This is explained in the paragraph beginning just before 459. A changing temporal or spatial relation between knower and the things known, when this change is known, makes a change in the knowledge. If I know that something is on my right, and then that it is on my left, then these are two different pieces of knowledge and my knowledge has changed. If I move from the right of a pillar (which has no knowledge) to the left, I change and the pillar doesn't; if you move from my right to my left and I don't know it, you change and I don't, like the pillar. But if you change position relatively to me and I know it, then there is a change in my knowledge, so the philosophers say. Now change is impossible in God, so he can't know the changes in things.
Read 459.8-20.
So Ghazali denies that knowledge must change if it is knowledge of changing things. His example could be clearer: "Suppose God has created in us a knowledge that Zaid will arrive tomorrow at daybreak". The difficulty is that the word "tomorrow" has a changing reference as time passes. Instead, suppose God had created in us a knowledge of Zaid's time of arrival as 6.00 am on 6th October 1992. This could be a permanent and unchanging piece of knowledge, true before, during and after. God's knowledge could be like this. But still there is a difficulty: can God know that it is now 6.00am on 6th October 1992? - or that it is not? It would seem not.
Aristotle held that God knows only himself. Avicenna differs slightly from Aristotle on this point, and says that in knowing himself God also knows creatures, but only in general terms. Ghazali is saying that this half-way position is untenable: if God can't know changing things because he can't change, then he can't know the many sorts of creatures, even with a general knowledge of each sort, because there are many sorts, and there cannot be multiplicity in God. So Avicenna had better go back to Aristotle's position, "the path of your fellow philosophers". (Notice several slight differences between Avicenna and Aristotle. Aristotle says that the world is eternal and does not say that God creates the world: Avicenna says that the world is eternal and eternally proceeds in a necessary manner from God, who in that attenuated sense creates it. Aristotle says that God knows only himself; Avicenna says that God's knowledge of himself is also knowledge in general terms of creatures - not of individuals, and not of temporal events. Aristotle says that natural processes are for the sake of ends, but does not say that God appoints the ends. Avicenna says that God appoints the ends. Avicenna is an Aristotelian trying to make more room for religion.)
Read the first paragraph of Averroes' comment, to the beginning of 461.
"The assimilation", i.e., the likening, or drawing of analogies. "The cause of his [man's] perception is the thing", whereas God's knowledge is not caused by the thing but rather causes the thing. (Does Ghazali's argument depend on analogies between divine and human knowledge?)
Read the next paragraph, to 461.14.
"This is an answer which cannot be understood from the nature of human knowledge"; Doesn't this show the Ghazali's argument does not depend on analogies with human knowledge? "They are unified in the knowledge that comprehends them" seems to mean that God knows all the different sorts of creatures by a knowledge that is one and simple; though the last clause of the sentence does not fit this interpretation. I'm not sure what the last clause means.
Read the next paragraph, to 462.14.
If God can know all different sorts of creatures by one simple knowledge, why can't he likewise know all the different individuals? Averroes' answer seems to be that God's knowledge is unlike human knowledge in being active, not passive, creative, not receptive. The translator in his note 5 quotes Plotinus to the effect that God thinks created things only as they exist in himself as their cause, and as they exist in himself they are not a plurality. "Thinking its own self, in its own self it thinks the things, which therefore are identical with it" (Plotinus). Similarly, at the end of the paragraph Averroes says that "God does not think other things as being other than himself", "he thinks them as being identical with his essence". Doesn't this amount to Aristotle's position, that God knows himself and does not know other things?
Read the next two paragraphs, to the end of 463.
So God knows the existents we know, but in a superior way, in their superior existence - i.e., he knows things as they exist in himself as their source.
Read Thomas Aquinas on this topic, Readings, p.124-5, fifth article (Summa theologiae, 1, q. 14, a. 5).
To return to Averroes, Readings, p.98 (or van den Bergh, p. 280). Notice the remark, "One who mentions this truth where it should not be mentioned"; compare 428.12 above. How God knows creatures is the kind of philosophic question that should not be raised before ordinary believers who would find it unsettling.
Read the next paragraph from Ghazali, to 464.8.
"The second refutation"; the first began at 459.8 or thereabouts. The two objections are to the philosophers' claim that God cannot know changing things because this would imply that God changes. The first objection was that God could have dated knowledge, of Zaid's time of arrival at 6a.m. on October 6th etc. The second objection, stated here, is that maybe God does change - not that Ghazali thinks this himself, but the philosophers cannot consistently reject it, he says, because they say that the world changes though it is eternal. The Mu'tazillites and Karramites are schools of theologians Ghazali disagrees with: they say that God can change. True believers, Ghazali, says, refute them by saying that what changes must be temporal, not eternal, and God is eternal. But the philosophers cannot say this, since they say that the universe is eternal but all the time changes, as the spheres revolve. This is an argumentum ad hominem: that is, not something the arguer himself believes, but a point put forward to draw attention to the other side's inconsistency. They must choose between this and the other position.
We will skip over this discussion, especially since it involves back reference to parts of the book we haven't read. Read the last paragraph from the passage from Ghazali and then Averroes' reply, i.e. from 465.13 to the end of the thirteenth discussion.
Now read Thomas Aquinas on the topics of the Thirteenth Discussion, in Readings, pp.122-130 (Summa theologiae, 1, q. 14).
Before leaving Averroes there are several more things to do, involving a fair bit of time. Now might be a good time for a coffee break or a good night's sleep.
Now go to pp.192-4, Avicenna's Physics, and read to the 3rd line on p.194.
Now go to p.210 and read Gilson's summary of Avicenna's theology, to p.216.
Notice on p.211 the references to the neo-Platonist Proclus. The Algazel referred to on the same page is the Al-Ghazali we've just been reading. A little book in which he summarised the theories of the philosophers preliminary to refuting them in the Incoherence was translated into Latin and the Latins thought that these theories were Algazel's own. (The Incoherence was not translated until the fourteenth century). The universe described on pp.213-4 generated from the First through many levels is typically NEO-Platonic; compare Supplement, p.3 (Encyclopaedia Britannica, "Plato and Platonism"). Notice near the foot of p.214 the "giver of forms", which is the separate Agent Intellect: this is an agency which gives forms to sublunary things and thinks thoughts into the minds of individual human beings. The Agent Intellect is separate from our individual intellects, but the cause of our thoughts.
Now read the section on Averroes, pp.216-225.
Bear in mind that you have skipped some parts of this chapter. It would be worth reading right through. Now turn to Supplement, p.114 and look at several extracts from Aristotle. Physics, book 1, ch.7, analyses change in terms of an underlying something which first has one character and then loses the character and acquires the opposite - a substrate that loses one form and acquires another. Notice the numbers down the margin. The second number reads "190a1". At 190a14 notice and highlight "there must always be an underlying something", and a few lines later "one part survives, the other does not: what is not an opposite survives". Read from the beginning of the chapter to the end of this paragraph.
At 190a33 or thereabouts underline other and plain ("Now in all cases other than substance it is plain"), and at 190b1 underline "substances, too"; this is not so plain, but it will appear "on examination" as he says in the next line. Read to 190b5. At 190b5, "comes to be without qualification", that is, just comes to be, not comes to be something (hot, musical or whatever): this is a back reference to 190a32-3. Now read the rest of the chapter.
How many principles are there of a changing being? Two or three: matter and form, or matter and two forms (the one displaced and the one acquired). The two forms are opposites, musical and non-musical; one is the privation of absence of the other ("non-musical" indicates the absence of the forms acquired by musical training).
This obscure passage is about all Aristotle ever says about the Agent Intellect and the Possible Intellect. Thought becomes all things: when you think of something your thought becomes what you are thinking of, though in a non-material way: when you think of a hot body, heat comes to exist in your thought, though your mind does not become a hot body. The mind as capable of becoming is the potential or possible intellect. Something must make it become: this is the agent intellect. At line 15: "there is another which is what it is by virtue of making all things" i.e. it brings them into existence in your mind. Thought in this sense, as making, is separable, impassible, unmixed: this remark suggested to Avicenna and Averroes that the Agent Intellect is separate from the individual person. Turn back and look briefly at chapter 4: notice the second line, which suggests that the mind might be spatially separate. (The whole knowing part, not only the Agent Intellect but, as Averroes held, the possible intellect also.) Read on a little further: the thinking part of the soul must therefore be, while impassible, capable of receiving the form of the object, without being the object. "While impassible", "without being the object" means that the mind does not actually become hot physically when heat comes to exist in your mind.
Read now on p.118 the chapter from Aristotle's Metaphysics on the four causes. Think of these as the four becauses. Why does a chair burn? Because it is made of wood, its material cause. Why does it support a sitting person? Because of its shape, its formal cause. Why has that form been imposed on that matter? Because someone made it (the efficient cause), because he wanted something to sit on (the final cause). Read the chapter.
Now read Supplement, p.98
The translators would not have undertaken their laborious task - or if they had we would never have heard of them - if there had not been in the many schools in the towns of Europe a public ready to buy copies of their translations. The logic schools provided a public interested in philosophical translations; they quickly became schools of philosophy complete, not just of logic. Their numbers increased as potential students got to hear of the new material. At first the church, notably in Paris, tried to ban the teaching of Aristotle's physics (natural philosophy) for the same reason as Muslims had not liked it, namely that in these works Aristotle taught things not easy to reconcile with religion, e.g. that the world is eternal, that God knows only himself, and (as Avicenna and Averroes interpreted him) that there is only one Agent Intellect for the whole human race. The ban on teaching Aristotle's natural philosophy was swept away by commercial pressures. The schools were businesses, the students wanted Aristotle. Teachers at Toulouse, outside the jurisdiction of the bishop of Paris, advertised that in their schools you would read all of Aristotle's works. So the total ban was replaced by a temporary prohibition envisaging the eventual use of Aristotle. Open the Supplement, p. 81, and read from L. Thorndike, University Records and Life, document 20.
Aristotle's works were in fact never expurgated, and soon became, unexpurgated, the prescribed texts in the universities.
Some comments. The Chancellor was not part of the University. He was the bishop's deputy, who licensed schools. He is to swear that in future he will not license new masters without consulting the university. The rest of the document sanctions rules of various kinds that the university had begun to make, about times of classes, curriculum etc. The Calendar was important from the beginning, since the members of the university visited one another's schools. The next document you have already read. Read the next, document 25, which illustrates the working of the university as an interest group. Pause.
Read document 26.
The determinations that this document regulates were the trial teaching period by which a bachelor proved his fitness to be made a master ruling a school in his own right. ("Determining" meant deciding a question after it had been disputed by the students and bachelors.)
A digression on terminology. The terms university, proctor, etc. were terms of Roman law; Roman law had come into use again. A proctor or procurator in Roman law is a person who represents some person or body. The term university meant in Roman law a body of people, a corporation of any sort. The terms university and college originally had no special reference to education. They were more or less interchangeable terms for a corporation of any kind. The college of cardinals is not an educational institution but the body of cardinals. Colleagues are members of a college, other members of the same body, of any sort. "University" similarly meant any corporation. The university of masters at Paris was the corporation of men who had schools at Paris.
Remember that the university prescribed the curriculum so as to guarantee to prospective students that the schools of Paris would teach thoroughly the books then regarded as the best.
As I mentioned before, the text books in the medical faculty were translations of Averroes and Avicenna. The textbooks in theology were the Bible, and a book called The Sentences, compiled by Peter Lombard. It consisted of extracts from the Church fathers, Augustine, Gregory and so on (not just sentences but lengthier passages - "sentence" here means opinion or judgment). The judgments of the fathers were sometimes in conflict; in fact Peter Abelard had made a collection of extracts from the fathers called Sic et Non (yes and no). So Peter Lombard gathered together conflicting passages on various theological questions and offered suggestions for harmonising them. Bachelors and Masters in theology lectured on the Bible and on the Sentences.
In law there were two divisions, Civil law and Canon law. Civil law meant Roman law. The textbook was Justinian's Corpus, especially the Digest, which consisted of extracts from various ancient legal writers arranged topically and harmonised: the Digest may have been Peter Lombard's model for the Sentences. In Canon law the textbook was a similar compilation by the monk Gratian. Turn to Supplement, p.90, and read the extract from Gratian (from E.R. Fairweather (tr.), A Scholastic Miscellany (London: SCM Press, 1956), p. 243.
Notice the title - The Concord of Discordant Canons. Canons are rules of Church law; Gratian's aim was to harmonise conflicting rules. The passages headed "Gratian" are his contribution. The bulk of the work consists of extracts from other writers, in this example from Isidore, often from Augustine, Gregory and other Fathers.
Go to Thomas Aquinas (continued)
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