On Aristotle Physics 2

224 Pages·2014·1.05 MB·English

by  Simplicius

Introduction
Part One
Richard Sorabji
Book 2 of the Physics is arguably the best introduction to Aristotle.
It contains ideas that are central to his thought, but also of continuing
philosophical importance today.
In Chapter One, he defines nature, because his subject is natural
science, and distinguishes natural objects from artefacts.
In Chapter Two, he distinguishes the subject matter of the natural
scientist from that of the mathematician, although he relates the two.
In Chapter Three, he introduces his seminal distinction of the four
causes, or four modes of explanation.
In Chapters Four, Five and Six, he explains what both luck and
chance are: various kinds of coincidences. He does not yet make the
anti-determinist decision, which I believe he later makes in Metaph.
6.3, that coincidences lack a cause, since they lack an explanation.1
After resuming in Chapter Seven the theory of four causes, he
argues in Chapter Eight that there is purpose in nature, even in the
absence of consciousness. A rival theory of purposeless natural selec-
tion can safely be rejected because it lacks the refinements of the
modern theories of natural selection.2
In Chapter Nine, Aristotle shows how matter or the material cause
explains: not as materialists think as a necessitating cause, but as a
prerequisite presupposed for the attainment of natural purposes.
What does Simplicius add to Aristotle’s bold theory of nature?
Simplicius cites the interpretations of many predecessors, reserv-
ing a special rivalry for the greatest commentator of the former
Aristotelian School, Alexander of Aphrodisias. Alexander’s commen-
tary on the Physics is lost, except for some newly discovered excerpts
from the later books, currently being edited by Marwan Rashed, who
has used them to argue that Simplicius’ reports of Alexander are
unfair to him.3
1 Sorabji (1980) ch. 1.
2 Sorabji (1980) chs 10-11.
3 Rashed (1996).
2 Introduction
Simplicius also provides some very useful summaries of five dis-
tinct definitions of nature (CAG pp. 282,30-285,12), of Aristotle’s first
two chapters (309,2-31), and of his account of luck and chance (356,31-
358,4).
Discussing nature, Simplicius sees a problem about the relation of
soul to nature. Aristotle might arguably have been willing to treat
the souls of living things as one kind of nature,4 and Alexander takes
this to have been Aristotle’s view at least for the case of the suppos-
edly living heavens.5 But the Stoics disagreed, concentrating on the
case of plants. Long before Descartes,6 they rejected Aristotle’s re-
cognition of a non-conscious soul in plants with merely nutritive
functions. Instead they substituted nature as the property of plants
and contrasted soul.7 This may help to explain why Simplicius and
Philoponus as reported by Simplicius8 can take nature and soul to be
distinct agencies in living things. Despite this, they think that living
things can be acted on by both soul and nature, but they also believe
this calls for explanation, and Philoponus complains that Aristotle is
not consistent in explaining celestial motion by soul as well as nature.
Elsewhere, Philoponus identifies soul and nature in living things.9
If soul and nature are distinct, what is the difference? Simplicius
says that nature is a principle that permits things to be moved
passively rather than one that causes motion.10 Aristotle had needed
this idea in order to pave the way for his divine unmoved mover. For
this he uses the rule that whatever moves is moved by something,
and by something sufficiently distinct from itself. But how does this
rule apply to things which move in accordance with their own inner
nature, like falling rocks and rising steam? Their inner nature is not
sufficiently distinct from them for Aristotle’s purposes. He therefore
insists that their motion requires a releaser, which acts as an acci-
dental cause: the person who dislodges the rock, or takes the lid off
the kettle, or boils the water in the first place. The inner nature of
the rock or steam thus permits it to be moved passively by the releaser
or generator. But does this distinguish nature from soul? For in the
same book Aristotle says that the soul of an animal also has to be
stimulated by the outer environment.11 But he there also insists that
4 Sorabji (1988) 222.
5 ap. Simplicium in Cael. 380,29-381,2; 387,12-19; in Phys. 1219,1-7.
6 Descartes, ‘Reply to objections brought against the Second Meditation’, §4, in the
fifth objection, translated by Haldane and Ross, vol. 2, p. 210.
7 Galen, PHP 6.3.7 (SVF 2.710); Clement, Stromateis 2.20 (SVF 2.714).
8 Simplicius below in Phys. 262,13-263,11; 286,20-287,25; 379,28-9; also in Cael.
387,12-19. Philoponus, contra Aristotelem bk. 2, fr. 49-50, translated in this series from
Simplicius, in Cael. 78,12-79,14; 199,27-35 Wildberg (1988) 160-5.
9 Philoponus, in Phys. 2 197,4-5.13-22; 198,7 Lacey (1993).
10 Simplicius below in Phys. 287,10; also in Cael. 387,12-19.
11 Phys. 8.2, 253a7-20; 8.6, 259b1-20; cf. DA 3.10, 433b13-19.
Introduction 3
in a certain sense soul is unmoved, or is moved only in a restricted
sense.12 This makes it different from nature.
In discussing the natural scientist as against the mathematician,
Simplicius quotes a precious summary, at page length, of Posidonius’
lost treatise on Meteorology, on the subject of mathematical astron-
omy.13
On the subject of causes, Simplicius gives the Neoplatonist list
which expands Aristotle’s four causes to six.14 There is the instrumen-
tal cause15 and the paradigmatic cause.16 Aristotle had called his form
or formal cause a paradigm, but he did not accept the Platonic Forms,
which are what constitute the Neoplatonist paradigmatic cause.
Aristotle’s efficient cause is rarely called a poiêtikon cause by
Aristotle himself, but by the later commentators. Moreover, the late
Neoplatonist commentators added a twist. Simplicius tells us of a
whole book written by his teacher Ammonius, to show that Aristotle’s
God was not only a final cause of motion, but also an efficient cause
of existence for the universe.17 A poiêtikon cause is here a sustaining
cause of being, not merely an efficient cause of other effects.
Simplicius reflects another Neoplatonist view about causation
when he allows that causes need not be like their effects, in those
cases where they are greater than the effects.18 He is talking about
the Platonic Forms as causes. An even clearer example in Plotinus is
that of the One which is beyond the Forms.19
Simplicius is also well versed in the Stoic sub-distinctions among
causes.20 The Stoics took from Plato21 the idea of joint causes (sunai-
tia). These used each other in order to produce the effect. Co-operating
causes (sunerga) are defined by the Stoics as intensifying the effects
of other causes or making them easier to achieve. They are not, like
sunaitia, on a more or less equal footing with each other. The Stoic
containing or cohesive cause (sunektikon) is the pneuma, i.e. the
elements of fire and air which sustain things by permeating them and
holding them together.22 Containing causes are also sufficient causes
which explain the behaviour of the things they hold together. They
12 Phys. 8.5, 258a7; a19; DA 1.3, 406a3; b7-8; 1.4, 408b5-18; 2.5, 417a31-b16; 418a1-3.
See Sorabji (1988) ch. 13.
13 Below in Phys. 291,21-292,31.
14 ibid. 316,23-6.
15 ibid. 316,9.10.25; 317,24; 318,24.
16 ibid. 298,17; 316,24; 317,31; cf. p. 363.
17 Simplicius, in Phys. 1361,11-1363,12, translated with discussion in Sorabji (1988)
ch. 15.
18 Below in Phys. 297.
19 Plotinus 6.7.17; Sorabji (1983) 315-16.
20 Below in Phys. 316,25; 326,15-16; 359,18-21; 360,16; 370,15. For the Stoic sub-
distinctions, see Frede (1980) 217-49.
21 Plato, Timaeus 46C.
22 Sorabji (1988) 85-9.
4 Introduction
need to be triggered by prior or antecedent causes (proêgoumena).
Simplicius does refer to nature acting as something prior
(proêgoumenôs),23 but if he means to be talking of the Stoic prior or
antecedent causes, he has altered them. For the Stoics would think
of a thing’s nature as a cohesive cause. Simplicius refers also to
containing causes.24 He may be thinking of a containing cause in a
non-Stoic way as one which incorporates others,25 but he may have
in mind the Stoic idea that it most fully accounts for behaviour.
Simplicius also introduces a causal relation of his own: in some cases
luck is responsible for causing other causes to achieve their end.26
In the section on luck and chance, Simplicius attacks both those
who ascribe nothing to chance and those who ascribe too much. The
latter are attacked also in his commentary on Epictetus as leaving
no room for what is up to us.27
There is a discussion of missing a great evil or a great good by a
hairsbreadth (para mikron). We think the former a godsend and the
latter a disaster, for, as Aristotle says, ‘the mind proclaims them [the
great evil or good] already yours’ (197a29). It was a Stoic view that
things are often judged good or bad and give rise to emotion only
because they are unexpected. We should counter this by expecting
loss. Epictetus makes this point in his Manual, 3 and 21, on which
Simplicius commented. Nonetheless, Simplicius does not here make
the Stoic point that thinking a narrow miss a godsend or a disaster
is purely a matter of expectation and so irrational.
In the section on purpose in nature, Simplicius refers to the old
debate on whether the clever behaviour of animals is due to intellect
and reason, to mere instinct or nature, or to something intermediate:
a natural self-awareness which falls short of intellect and reason.28
Intellect and reason were denied to animals by Aristotle and the
Stoics, but ascribed by some Platonists, most notably by Plutarch and
by Porphyry in On Abstinence from Animal Food, which is to be
translated in this series.29 Porphyry’s view might seem to follow from
Plato’s idea that human souls can be reincarnated in animal bodies.
Accordingly, Plato describes some animals as possessing reason, even
if it is disused.30 I believe, despite conflicting evidence, that Porphyry
did at least entertain Plato’s idea of the transmigration of human
souls into animals. Conflicts in the evidence, I think, are due to
23 370,15.
24 326,15-16.
25 See note 243 to the translation.
26 360,15f.: see note 343 to the translation.
27 Simplicius in Epicteti Enchiridion 1, lines 175-97 (Hadot).
28 Sorabji (1993) ch. 7; Simplicius below, 378,27-379,22.
29 cf. Sorabji (1993) chs 1-7.
30 Plato, Timaeus, 91D-92C.