Copyright © 1996 R.J. Kilcullen
The following summary of the neo-platonic world-picture is based on the article "Plato and Platonism" in The New Encyclopaedia Britannica
1. There are many levels of being, in a hierarchy (degrees, ladder, scale). Lowest is our world, which is mutable, existing in space and time, perceivable by the senses. There are super-sensible realities.
2. Each level eternally 'emanates' from a higher level (i.e. is caused by it - but not like causation we are familiar with, in time and space: more like logical derivation).
3. The perfection of each level (its persistence in being, stability, full realisation) requires 'turning back' to the higher level in contemplation and love. The 'good' (goal) of each being is the higher being which is its source.
4. Each level is an expression, image, or reflection of a higher level, which is its archetype.
5. Degrees of being are degrees of unity. Each lower level is less unified, more multiple, a dispersed image of the archetype. The highest degree of unity is simplicity, absolute identity of subject and attributes. The beings we know are composite; their existence requires the unification of parts or elements or components which remain distinct even when unified.
6. Our thoughts are inadequate to the higher levels. The highest level is unimaginable and inconceivable to us; all we can say is that it is like the most perfect things we know, but also unlike. We must speak of it in analogies and negations. The best names for it are The One and The Good (rather that Being).
Academics: Carneades, BC 214-185; Plutarch, AD 46-120.
Peripatetic: Alexander of Aphrodisias, fl. 200 AD.
'Platonists' : Plotinus (Rome), 205-270; Porphyry (Rome), 250-305; Iamblichus (Syria), 250-325; Proclus (Athens), 412-485; Ammonius son of Hermeias (Alexandria), 436-517; Simplicius (Alexandria, then Athens), fl. 515-545; John Philoponus (Alexandria), 490-570.
Christian platonists: Clement of Alexandria, 150-215; Origen (Alexandria and Palestine), 184-254; Augustine (Carthage), 354-430; Boethius (Rome), 480-524; John Philoponus.
Neoplatonic passages in Boethius: p. 99 (there must be a supersensible good); pp. 102-3 (identity of all goods in the supreme good); p. 105 (identity of supreme unity and goodness); p. 110 (God as unifier); pp. 135-7 (providence and fate); pp. 156-66 (foreknowledge and eternity). (Compare Proclus, Elements of Theology (PA/4400/.I6), propositions 1 (p. 3), 13 (p. 15), 52 (p. 51), 55 (p. ), 127 (p. 113), 141 (p. 125), 170 (p. 149)).
Page references to Boethius are to Watts's translation, Penguin Classics. References to Plato use the Stephanus numbers.
Background to Boethius' political activities: Plato, Republic 514 ff (the cave), 473d (conjunction of political power and philosophical wisdom), 347 (need to prevent power falling into the hands of the wicked). Cf. Consolation, p. 41.
Boethius' Writings: On Arithmetic, Geometry, Astronomy, Music (cf. Plato, Republic 525 ff). Intended to translate and explain the works of Aristotle and Plato, and to show 'that the Aristotelian and Platonic conceptions in every way harmonize' (Cf. Cicero, Academica I.iv, II.v; Augustine Contra Academicos III.xix.42). Theological tractates; Consolation. See Courcelle, Late Latin Writers, ch.6 (esp. p. 316 ff).
(2) So what is happiness? 'A condition provided with all that is good, a condition of self-sufficiency, with no wants', p. 81. Cf. Aristotle, NE, I.7. It must be the case that in the true good 'sufficiency, power, glory, reverence and happiness differ in name but not in substance', p. 95 (cf. Plato, Protagoras, 349 ff). Only in God is this true; so God is the true goal of human life, pp. 99-104. God is the good at which all things aim, the one which unifies all (cf. Plato, Republic, 508 ff).
(3) God's providence, p. 104 ff. The world is governed 'willingly' (cf. Plato, Statesman, 276e). But then why is there still evil, which often goes unpunished? Answer: an evil man is worse off if not punished (Plato, Gorgias, 477-479), while virtue requires no reward (Plato, Republic, 445ab). 'Goodness cannot be removed from those who are good; therefore goodness never fails to receive its appropriate reward', p. 124. But all the same, 'no wise man prefers being in exile...', p. 132 (cf. Cicero, De finibus, V). This is the problem of evil, which raises questions of providence, fate, chance, divine foreknowledge, predestination and free-will, p. 134. (See Pierre Bayle, Dictionary, 'Paulicians'.)
(4) Providence is one and simple (God himself), fate is the multiple participation of providence in created things, p. 135. 'Everything is freer from fate the closer it seeks the centre of things', p. 136. Things seem disorderly because we cannot see from God's standpoint. God is free, not subject to fate. We are free, despite God's foreknowledge (cf. Augustine, City of God, V.10 and Cicero, De fato (appendix to De divinatione)). But how can God foreknow our acts unless they are subject to fate, and necessarily caused, p. 152? This question assumes that the character of knowledge depends on the object known; in fact knowing is an act, and its character depends on the nature of the knower, pp. 157-9. God's eternity is not an infinitely long life, but simultaneous. So he knows our future acts 'as though they are happening in the present', p. 165. His knowing them does not impose or presuppose any necessity, pp. 165-8.
1. If the first, then the second; but the first, therefore the
second.
2. If the first, then the second; but not the second, therefore
not the first.
3. Not both the first and the second; but the first, therefore not
the second.
4. Either the first or the second; but the first, therefore not
the second.
5. Either the first or the second; but not the second, therefore
the first.
See R.W. Southern, St Anselm and his Biographer (BX4700/.A58).
Lived 1033-1109. Italian, travelled to France, became a Benedictine monk at Bec, abbot Lanfranc, later the first Norman Archbishop of Canterbury. Anselm abbot of Bec 1078, Archbishop of Canterbury 1093.
At Bec author of prayers and meditations in a new, more heartfelt style; see Southern, p. 47.
Also wrote at Bec the Monologion (1077) and Proslogion (1078).
'The one thing that makes that object beautiful is the presence in it, or association with it, in whatever way the realtion comes about, of absolute beauty... it is by beauty that beautiful things are beautiful' (Plato, Phaedo, 100d.
'In all these good things... we could not say that one was better than another... unless a conception of the good itself had been impressed upon us, such that according to it we might both approve some things as good and prefer one good to another'; Augustine, De Trinitate, VIII.iii.4.
Either A or B.
Not B (because C).
Therefore A.
Therefore either D or E.
If E then 1, or 2, or 3.
If 1, then not E.
Therefore not 1.
Not 2.
Not 3.
Therefore not E.
Therefore D.
To prove P:
1. Q (some true premiss)
2. Assume not-P
Then 3. an argument is constructed using 2 (and perhaps various
other premisses as well) to prove not-Q
4. Then (combining 1 and the conclusion of 3) Q and not-Q, which
is absurd.
5. Therefore P (negating the assumption that led to the
absurdity).
Assume (a) that G does not exist (the opposite of what we want to prove)
Then, since (b) it will then be possible to think of another being exactly similar to G only existing, and since (c) a being that exists is greater than an otherwise exactly similar being that does not exist, it will follow (d) that G is not that than which nothing greater can be thought, i.e. G is not G - which is absurd.
Therefore (negating (a)) it is not true that G does not exist; i.e. that than which nothing greater can be thought does exist.
For 'that than which nothing greater can be thought' let us write 'G', and for 'G exists' write 'GE'.
3. With the exception of things like the a painter's idea, which exist in a mind in the sense that this person can make them really exist, real objects do not exist in a mind, but in reality.
4. I can understand something of a man who turns out to be non-existent, because there are other men. Anselm's G is unique; so until we know its real existence, we can understand nothing of it. The conception the term evokes in the mind of someone who does not know already that the object exists is merely a 'movement of the mind... attempting to image'.
5. The doubter does not concede that G is greater than any real object, so does not concede that it is greater than all. So that it is greater than all is not conceded, so no contradiction results (that it is, and is not, greater than all) from the supposition that it exists only in the mind.
6. The island analogy.
7. Comment on chapter 3, that God cannot be thought not to exist. See 5. On the claim that 'everything else there is, except You alone, can be thought of as not existing': if I can think of myself as not existing, then why cannot I think of God as not existing? If I cannot think of myself as not existing, then there is something besides God which can not be thought as not existing.
'Moreover': a new argument, by-passing the notion of existence in the mind. G cannot be thought except as having no beginning. But if something does not exist, but can be thought of as existing, then it can be thought of as beginning. Therefore G either cannot be thought of as existing, or exists. It can be thought of as existing. Therefore it must exist.
'Further': no one who denies or doubts G's existence doubts that (1) if G existed it would not be capable of not existing actually or in the mind (otherwise a greater could be thought); but (2) what can be thought as existing but does not exist could, if it existed, possibly not exist either actually or in the mind. Therefore (3) if G can be thought it must exist.
[Approximate structure of argument:
(2) If T and not GE, then if GE then (not A or not M);
(1) If GE then not (not A or not M); therefore
(1.1) not (T and not GE; therefore
(1.2) if T, not not GE; therefore
(3) if T, GE.]
'However': (1) Suppose not GE and T. (2) If T and not GE, then if GE, not G. Then (3) G would not be G.
'I... further': If x, in all its parts, does not exist here and now, then even if it exists there and then, it can be thought of as wholly non-existent, always and everywhere (down to p. 173, line 9). If G exists and can be thought not to exist wholly here and now, then G is not G.
Since we can construct the above arguments about G, we do understand something of it.
[II] If we understand it, it does exist in the mind, and the argument of ch 2 follows.
[III] That it cannot be thought not to exist - either it is not thought, or it is thought as necessarily existent. Otherwise, it would be thought as possibly having a beginning or end - and it cannot be.
[IV] Rejects suggestion that 'understood' be substituted for 'thought'. You can (in a weak sense) think of yourself as non-existent - only G cannot (in even this sense) be thought of as non-existent.
[V] 'That than which there is nothing greater' cannot be substituted for 'that than which nothing greater can be thought'. The reductio ad absurdum would not work.
As archbishop he was involved in the 'investiture controversy', coming into conflict with William II and Henry I. Much of his time as archbishop was spent in exile. (Cf. later Thomas a Becket.) See English Historical Documents, vol. 2, p. 650 ff (DA/26/.E56); A.L. Poole, From Domesday Book to Magna Carta, p. 172 ff (DA/26/.09. vol 3).
Southern's summary of the argument of Cur deus homo (p. 92):
A.1 Man was created by God for eternal blessedness.
2. This blessedness requires the perfect and voluntary submission
of Man's will to God.
3. But the whole human race is guilty of disobedience.
4. Any deviation of Man's will must either be punished by
deprivation of blessedness or rectified by an offering greater
than the act of disobedience; there can be no free remission.
5. No member of the human race can offer anything to God beyond
his due obedience: there is no human capital with which to redeem
the past, not to speak of the present and future.
6. Therefore the whole human race must forfeit the blessedness for
which it was created.
B.1. On this argument God's purpose in the creation of man has
been frustrated.
2. But this is impossible.
3. Therefore a means of redemption must exist.
4. But the offering necessary for redemption ought to be made by
Man.
5. And since Man has nothing to offer, it cannot be made by Man.
6. The offering required is greater than the whole existing
Creation.
7. Nothing is greater than the whole Creation except God.
8. Therefore only God can make this offering.
9. Since only God can, and only Man ought to make this offering,
it must be made by a God-Man.
10. Therefore a God-Man is necessary,
11. Therefore the Incarnation is necessary.
Matter and form are not things, capable of separate existence; they are, however, 'realities', not fictions. (N.B. there are realities other than complete things.) A material substance is a composite unity, consisting of matter and form united.
Prime matter has no characteristics, other than capability of being informed: it is 'pure' potentiality. Characteristics are all on the side of form. The essence (definition, nature, quiddity) of a thing is its form: but in the case of material things, its form has a relation to matter (it is the form of a material being), and that must be mentioned in the definition. (See Thomas, On Being and Essence, Ch. 2.)
Aristotle calls matter 'potency' or 'potentiality' and form 'act': substantial form is first act, accidental forms actualize the substance's potentiality for acquiring some accident. Thomas adds that existence is an act, to which the corresponding potency is essence. Existence comes to things through form (though in the case of material beings the existence is that of the composite, not of the form. (Unless it is a form which is not altogether the actualization of matter, and then it belongs primarily to the form. The human soul is a form whose 'parts' are not in every case actualizations of parts (organs) of the body: the intellect is not.)
Psychology of knowledge: The external object acts on the knower, 'impressing' a 'species' (form). The soul reacts to this, and forms an 'express' species, in which it knows the object. Knowing is an action of the soul. Sensations are processed by the imagination, which images and remembers: the image in the imagination is called a 'phantasm'. The intellect abstracts from phantasms forms common to many remembered instances of objects of the same type (genus or species): these forms are 'universals'. Universals are like Plato's forms, but not at any stage existing separately, just by themselves: the exist in the external objects, in the sense organs, in the memory, in the intellect. The intellect as having the power to abstract is called the 'agent' intellect, as being able to receive and contemplate the abstracted forms, is the 'passive' intellect. These, and other 'powers' of the soul, are really distinct parts of the soul, but not capable of separate existence.
For more information on these topics see The New Catholic Encyclopaedia (Ref/BX841.N44), articles: Abstraction; accidents; act; essence; essence and existence; imagination; knowledge; knowledge, process of; knowledge, theories of; matter; phantasm; psychology; soul; soul, human, 4: philosophical analysis; substantial change.
'... the only ways of inquiry that can be thought of: the one way, that it is and cannot not-be, is the path of persuasion, for it attends upon truth; the other, that it is not and needs must not-be, that I tell thee is a path altogether unthinkable. For thou couldst not know that which is not (that is impossible) nor utter it; for the same thing can be thought as can be.... That which can be spoken of and thought needs must be; for it is possible for it, but not for nothing, to be...
One way only is left to be spoken of, that it is; and on this way are full many signs that what is is uncreated and imperishable, for it is entire, immovable and without end. It was not in the past, nor shall it be, since it is now, all at once, one continuous; for what creation wilt thou seek for it? how and whence did it grow? Nor shall I allow thee to say of to think, 'from that which is not'; for it is not to be said or thought that it is not. And what need would have driven it on to grow, starting from nothing, at a later time rather than an earlier? Thus it must either completely be or be not. Nor will the force of true belief allow that, beside what is, there could also arise anything from what is not; wherefore Justice looseth not her fetters to allow it to come into being or perish, but holdeth it fast; and the decision on these matters rests here: it is or it is not. But it has surely been decided, as it must be, to leave alone the one way as unthinkable and nameless (for it is no true way), and that the other is real and true. How could what is thereafter perish? and how could it come into being? For if it came into being, it is not, nor if it is going to be in the future. So coming into being is extinguished and perishing unimaginable...
Nor is it divisible, since it is all alike; nor is there more here and less there, which would prevent it from cleaving together, but it is all full of what is. So it is all continuous; for what is clings close to what is... But motionless within the limits of mighty bonds, it is without beginning or end, since coming into being and perishing have been driven far away, cast out by true belief. Abiding the same in the same place it rests by itself, and so abides firm where it is; for stong Necessity holds it firm within the bonds of the limit that keeps it back on every side, because it is not lawful that what is should be unlimited; for it is not in need - if it were, it would need all. But since there is a furthest limit, it is bounded on every side, like the bulk of a well-rounded sphere, from the centre equally balanced in every direction; for it needs must not be somewhat more here or somewhat less there. For neither is there that which is not, which might stop it from meeting its like, nor can what is be more here and less there than what is, since it is all inviolate...'
(From: G.S. Kirk and J.E. Raven, The Presocratic Philosophers (Cambridge, 1957), pp.269-76. Text preserved in Simplicius, commentary on Aristotle's Physics.)
See Plato, Sophist 241d-254. 'We shall find it necessary... to put to the question that pronouncement of father Parmenides, and establish by main force that what is not, in some respect has being, and conversely that what is, in a way is not... I suggest that anything has real being that is so constituted as to possess any sort of power either to affect anything else or to be affected... 'Are we really to say to be so easily convinced that change, life, soul, understanding have no place in that which is perfectly real - that it has neither life nor thought, but stands immutable in solemn aloofness, devoid of intelligence?' (From: E. Hamilton and H. Cairns (eds.), The Collected Dialogues of Plato (New York, 1961).)
See Aristotle, Physics I.7-9 (theory that the principles of change are matter, form and privation presented as counter to Parmenides' argument that change is impossible because 'what is' already cannot come to be, and 'what is not' cannot become anything because it is unreal.)
An underlying argument, that St Thomas follows part of the way, but does not want to follow to the end:
1. God is perfect, and has every attribute which connotes perfection.
2. Therefore he is absolutely simple - his being, knowledge, volition, action etc. are simply himself; and
3. He is fully actual, therefore immutable.
4. Therefore he cannot come to know, will, or do anything new.
5. Therefore the world is eternal. It is the only possible world (since God could not have done anything but what he has done). It is the best possible world (since God is wise, generous, good). Hence nothing is contingent.
6. The only fitting object of God's knowledge and volition is himself. There are no contingent beings or events (see 5), but if there were God could not know them. He cannot know or will creatures as they are in themselves (i.e. as other than God). If he knows or wills creatures the knowledge or volition is necessary and eternal.
7. Since God is perfect he needs nothing; since he is immutable he can be given nothing. He cannot be benefited, harmed, offended, placated, repaid. His mind cannot be changed by prayer, or by anything we do.
8. Human decisions have no real efficacy. God is omnipotent and causes everything (or permits everything) according to an immutable plan. There is no sin, or God causes sin.
9. God is simple, but we must think of him under a plurality of attributes. So our thought misrepresents his nature. As he is in himself he is unintellibile to us.
St Thomas accepts 1-3. See Summa theologiae I q3 a7, q4 a2, q9 a1, q10 a2.
He does not accept the rest. See -
(4) ST I q14 a15, q19 a7.
(5) A.O. Lovejoy, The Great Chain of Being. ST I q19 a3, q25 a5, a6; Summa contra gentiles I 81, 82, 85, 88; II 23, 24; III 72.
(6) ST I q14 a5, a6, a11, a13; q 19 a2. SCG I 48-53, 63, 65, 67, 74-8; III 75-6.
(7) ST I q23 a8; SCG III 95-6.
(8) ST I q19 a6 and a8; q22 a4, q105 a4 and a5. SCG II 6, 8, 15; III 66, 67, 69, 70, 73, 89, 90, 94, 162.
(9) ST I q3 prologue; q13 a2-7, a12.
Tacit premises:
(i) Whatever moves is moved by something or other;
(ii) A series each member of which is preceded by another is
infinite;
(iii) An infinite series has no first member.
Structure:
E & F > D
D & C > (tacit conclusion)
(tacit conclusion) & G > H
H & i > B
B & (suppose) J > K
K & ii > L
L & iii > M
M & O > (nothing moves)
(nothing moves) & A > not-J, i.e. P
(ii) If a being's non-existence is possible, then at some time it does not exist.
(iii) So on supposition (ii), at some time nothing existed.
(iv) What does not exist comes into existence only if caused by something that does exist.
(v) So nothing would ever have come into existence.
(vi) And nothing would exist even now.
(1) Suppose that every being is contingent.
(2) Suppose that the world has existed an infinite time in the past.
(3) If (2), then every possibility has before now been realized.
(4) Therefore of each being it will be true that at some time in the past it did not exist.
(5) Therefore at some time in the past all beings simultaneously did not exist, i.e. there was nothing.
(6) Therefore nothing would now exist (cf. iv-vi).
(7) But something does exist.
(8) Therefore either (1) or (2) is false.
(9) If (2) is false, then something other than the world must have caused it (and this means God).
(10) If (1) is false, there must be something necessary, either in itself or because it is necessitated by something else.
(11) But not every necessary being can be necessitated by something else (see first and second ways)
(12) Therefore some being is necessary in itself, and the cause of necessity in anything else that is necessary - God.
(1) If something acts always, or usually, in the best way, and attains the best result, then not by chance but by intention.
(2) This is true of some things without knowledge.
(3) But a thing without knowledge does not act for intended end unless directed by some being with intelligence. etc.
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