Chapter 2
The World-view of Aristotle’s Metaphysics 12
While Plato definitely teaches a beginning for the ordered cosmos, Aristotle
teaches no such thing. There is no beginning and no end to the world at large,
even if developments within the world may fluctuate dramatically. The
Aristotelian view of the cosmic building is important for developments in late
antiquity. The Neoplatonist school at a certain stage began to interpret his
philosophy based on the hermeneutical principle or dogma of a basic harmony
between the two giants of antiquity, Plato and Aristotle. Plato became the great
metaphysician, Aristotle the great logician and philosopher of nature.
Before we start on a description of the Aristotelian cosmos, some
comments on the translation of a Greek word should be made. The word ousia,
when used by Aristotle, is traditionally translated as substance. In the philosophy
of late antiquity, in Neoplatonist and Christian thought, the same word is usually
translated as essence or being. In the main I shall keep to these conventions of
translation, even if we no and then have to opt for other translations.
According to Aristotle, if the cosmos is a whole, substance is its first or
primary part.1 There are three kinds of substance, viz. (i) sensible and perishable,
such as plants and animals, (ii) sensible and eternal, such as the heavenly bodies,
and (iii) immovable substance.2 For Aristotle, the immovable substance is God,
the First Unmoved Mover, as we shall see.
In On the heavens (book 1, chapters 5-7) Aristotle argues that the body of
the universe is not infinite. Positively stated, it is finite. He further argues that
there cannot be more than one world, which is eternal, indestructible, and
ungenerated (chapters 8-12). All of this fits into the general picture of Metaphysics
12.
1
2
Met. 12, 1: 1069a 19-20.
Met 12, 1: 1069a 30-33.
The cosmos, as Aristotle describes it is spherical. There is, he says in
Metaphysics 12, only one heaven (ouranos), by which we may understand that
there is one cosmos, enveloped by this one heaven.3 He argument is as follows:
things may be one in kind, but many in number. However, numerical plurality
requires matter. Where there is no matter, there is only one member of the kind.
The prime mover, for instance, is one both in formula, i.e. definition (logos) and in
number (arithmos). Therefore, if there is only one prime mover, there is only one
thing that is eternally and continuously in motion. Consequently there is only
one heaven. Whatever is proved by this argument, Aristotle is in complete
agreement with Plato when it comes to the number of worlds.
The main argument of the first six chapters of the Metaphysics 12 leads to
establish the existence of the divine Unmoved Mover. The rest of the book, with
the exception of chapter eight, describes the nature of God. The argument for the
Unmoved Mover may be constructed thus from chapter six: motion existed
always and cannot be generated or destroyed. Time is bound to motion and
therefore it also existed always and is continuous like motion. The only
continuous motion is circular motion. — Now, these statements are of course in
need of proof, something he does not offer in Metaphysics 12. In Physics 8, 8-9,
however, there are some arguments: linear motion along a finite straight line
cannot go on continuously, since it comes to an end and then have to turn back in
order to go on, and therefore break the continuity. Circular motion along a finite
orbit is, on the other hand, the most complete motion, since it may go on
indefinitely without any interruption. Circular motion is, therefore, simpler and
more complete. An infinite rectilinear motion is impossible, but an infinite
circular motion is not. So a circular locomotion can be eternal. — Whatever one
thinks of this, it is essentially what Aristotle offers as his reasons.
The decisive part of the argument in Metaphysics 12, 6 is, however, the
next turn: in order to keep the continuous motion going on eternally, there is
3
Met 12, 8: 1074a 31-38.
required something that imparts such motion eternally. A mover is required. —
We shall return to the question of how the mover imparts motion below. —The
First Mover, consequently, must be a completely actualized Unmoved Mover,
since if not unmoved, it will be moved by another, and then we have an infinite
series of movers, something Aristotle considers impossible.
In order to fill in the picture of the Aristotelian cosmos, we shall take our
starting-point with a citation from chapter six (1074a 28-31):
For if we are to suppose that one motion is for the sake of another, the latter too must be for the
sake of something else; and since the series cannot be infinite, the end of every motion must be
one of the divine bodies which are moved through the heavens.
Several ideas are at work here. If an unmoved mover is to cause movement it will
have to work as a final cause. The movement will be for the sake of something. In
chapter eight, Aristotle makes an outline of heavenly motions. In Aristotle’s
model there are the following seven heavenly bodies: the moon, Mercury, Venus,
the sun, Mars, Jupiter, and Saturn. Each of these has its own sphere in which it
moves around the earth. Beyond these seven, here is the uttermost sphere of the
fixed stars, which is the first heaven. Now, in order to account for the movements
of these spheres Aristotle needs a total number of 55 spheres that move in a
system explaining the regularities and deviations we observe when looking at
the sky. Each of these 55 spheres have their own immovable substance or mover,
immovable in the sense that a higher sphere does not execute any force in order
to make what is below it move. What is below moves because what is above acts
as a final cause for the movement of the lower sphere. In the end the whole
system has to culminate in a First Unmoved Mover, beyond which there is no
other mover.
How, we must ask, is this kind of final causality possible? It is possible
because each immovable substance or mover is an intelligent being that desire
the uttermost perfection. This uttermost perfection consists in actualizing eternal
circular movement around the centre of the cosmos. The higher cause causes
motion by being an object of love (kinei de hos eromenon).4
Like in Plato the heavenly realm is animated by soul or intellect. Each
Aristotelian sphere has its own intellect that directs its intellectual love or desire
towards what is higher, and the by-product of this love is the relatively perfect
circular movement of the spheres.
Before we leave Metaphysics 12, we shall try to shed some additional light
of the nature of the First Mover and the effect he has on the cosmos. The God of
Aristotle is the arche of the heaven and nature, arche here probably meaning first
principle.5 God is not first principle, however, in the sense that he made the
world. Aristotle’s God is not an efficient cause. Even so his being has an effect on
the world, as we shall see below.
The life of the first principle is characterized by the activity of pleasure
(hedone), and this life of pleasure is executed as thinking (noesis) the best, which is
a thinking of thinking.6 In God the subject and object of thought coincide, and the
essence of God is this life activated as thought. God is a living being, eternal, and
the highest good.
In the beginning of chapter ten Aristotle uses two images to highlight
God’s relation to the world. He first says we should consider how the nature of
the universe contains the good or the supreme good: is it as something separate
and existing by itself, or as an inherent order (taxis)? Then he says the good is
probably present in both ways, and introduces his first image. In an army the
good is partly in the order inherent in it, and partly in the general, but since the
order depends upon the general, it is chiefly in him. Then follows a an interesting
statement about the cosmic arrangement:
4
Met. 12, 7: 1072b 3. Cf. the whole argument of chapter 7.
Met. 12, 7: 1072b13-14.
6
Met. 12, 7: 1072b14-30.
5
All things, both fishes and birds and plants, are ordered together in some way, but not in the
same way; and the system is not such that there is no relation between one thing and another;
there is a definite connection. Everything is ordered together to one end […]. 7
After this Aristotle illustrates his point with a new image. In a household, free
men have the least liberty act at random, while slaves and animals that do not
have the responsibility of free persons, act for the most part at random. — Now,
what is the point of this? In the household free persons enjoy the stability of
acting in accordance with set rules which they are responsible to keep up, while
those that do not carry this responsibility execute their activities, not just at
random or completely accidental, but relatively so within the rules guaranteed
by the free persons. Likewise, in the cosmos, the good order of the main
structures depends on the higher principles, basically on the First Cause, God.
Within this general order, other beings live and act, perhaps not in the complete
regularity of the higher principles, but still not quite accidentally or by chance,
rather mainly within the common order of nature.
The good order of the cosmos depends upon higher principles, in the end
it depends upon God himself. How? The perfection of divine self-contemplative
thought calls hierarchically the attraction of lover levels of spherical minds in
such a way that cyclical movement goes on eternally. God, it would seem,
possesses an infinite amount of power keeping himself going on with his own
activity as the eternally attractive final cause of being. There seems to be no
transitive or external activity either willed by God or occurring as a by-product
of the simple internal and intransitive activity of God. — We shall later see that
Plotinus introduces a concept of double activity that makes the first principle in a
modified way the efficient cause of the cosmos as well.
God being how he is, effects a certain attraction on levels of being, but it
would seem rather strange to claim any providence in the cosmos as seen by
7
Met. 12, 10: 1075a16-19.
Aristotle. Would not providence require a benevolent deity? However, the
question of providence shall be postponed to a later chapter. There are several
differences between Plato’s and Aristotle’s God. The God of the Timaeus
definitely creates because of goodness and care. He manifests his will in the
ordering and preservation of the cosmos. Aristotle’s God does no such thing, but
remains in his own self-thought, without even knowing whether there is a world
at all. However, this might be a too one-sided interpretation of Aristotle. Maybe
it is possible to think that Aristotle’s God, by thinking himself, thinks himself as the
final cause of being. In that case, it might even be possible to hold that this God
may understand himself as good in relation to the world, and even execute some
kind of provident activity, at least indirectly. We should keep this possibility in
mind.