Anaxagoras and the atomists
Anaxagoras and the atomists
C.C.W.Taylor
ANAXAGORAS
In the course of the fifth century BC the political and cultural pre-eminence of
Athens attracted to the city a considerable number of intellectuals of various
kinds from all over the Greek world. This phenomenon, the so-called ‘Sophistic
Movement’, is fully described in the next chapter; here it suffices to point out that,
in addition to the discussions of moral and theological questions for which the
sophists are more widely known, the activities of many of them included
popularization and extension to new areas, such as the study of the origins of
civilization, of the Ionian tradition of general speculative enquiry into the natural
world (see Chapter 2). Anaxagoras stands out from his sophistic contemporaries
as a truly original thinker, who sought not merely to transmit the Ionian tradition,
but to transform it radically in a number of ways, and in so doing to enable it to
meet the challenge of Eleatic logic, which had threatened the coherence of the
cosmological enterprise.
An Ionian from Clazomenae on the central coast of Asia Minor, Anaxagoras
was a contemporary of Protagoras and Empedocles. Aristotle says (Metaphysics
984a11–12: DK 59 A 43) that he was older than the latter, and (probably) that
his writings are later than those of Empedocles (the interpretation of the crucial
sentence is disputed). It is reliably attested that he spent thirty years in Athens
and that he was closely associated with Pericles, though there is some dispute
among scholars on when the thirty years began and ended, and whether they
were a single continuous period or discontinuous. Socrates in the Phaedo (97b–
98c: DK 59 A 47) describes reading Anaxagoras’ book as (probably) quite a
young man, but implies that he was not personally acquainted with him; some
have taken this as evidence that Anaxagoras had already left Athens for good by
about the middle of the century, but the evidence is weak. It is clear that, in
common with other intellectuals, his rationalistic views on matters touching on
religion (in his case, his materialistic accounts of the nature of the sun and other
heavenly bodies) made him unpopular in certain circles, and there is a tradition
(questioned by Dover [6.6]) that he had to flee from Athens (with the assistance
of Pericles) to escape prosecution. He is said to have died at the age of 72,
probably in the early 420s.
He appears to have written, as did Anaximander, a single comprehensive prose
treatise, referred to by later writers, such as Simplicius, by the traditional title On
Nature. In the Apology (26d, DK 59 A 35) Socrates states that it was on sale for
a drachma, about half a day’s wage for a skilled craftsman, which indicates that
it could be copied in well under a day. The surviving quotations from it (almost
all preserved by Simplicius), totalling about 1,000 words, therefore probably
represent quite a substantial proportion of it. In what follows I shall be concerned
with two central topics of this work, the nature of the physical world and the
nature and cosmic role of mind.
The Physical World
For all post-Parmenidean thinkers the central challenge was to show how natural
objects, including the world order itself, could come to be, change and cease to
be without violating the Eleatic axiom that what is not cannot be. Parmenides
had argued that that axiom excluded coming to be (for what comes to be comes
from what is not), change (for what changes changes into what it is not) and
ceasing to be (for what has ceased to be is not). Anaxagoras’ contemporary
Empedocles met this challenge by redescribing change (including coming and
ceasing to be) as reorganization of the four elements, earth, air, fire and water.
Those elements satisfy the Parmenidean requirement in its full rigour, since they
are eternal and changeless. What we observe and call change, coming to be and
destruction is in reality nothing but reorganization of these elemental
components; hence neither organic substances, such as animals and plants, nor
their components, bones, hair, blood, leaf tissue, etc., strictly speaking ever come
into being or cease to be. Put anachronistically, coming into being reduces to
elemental rearrangement, and what is reduced is thereby eliminated from a strict
or scientific account of the world.
Anaxagoras agreed with Empedocles that what is conventionally regarded as
coming to be and destruction is in fact reorganization of basic items. He asserts
this fundamental thesis in fragment 17:
The Greeks are not correct in their opinions about coming to be and
destruction; for nothing comes to be or is destroyed, but they are mixed
together and separated out from things which are in being. And so they
would be correct to call coming to be mixing together and destruction
separation.
The language is strikingly reminiscent of Empedocles’ fragment 9:
Now when they [i.e. the elements] are mixed and come to light in a man or
a wild animal or a plant or a bird, then they say it has come to be, and
when they separate, then they call that dismal destruction; they do not call
it as they ought, but I too assent to their usage.
But there is a crucial difference, in that Anaxagoras rejected Empedocles’ core
belief in the primacy of the four elements. Even if we accept (as I shall assume)
that Anaxagoras’ book was written later than Empedocles’ poem on nature, it
must be a matter for conjecture how far Anaxagoras arrived at his view of what
was physically basic through conscious opposition to the views of Empedocles.
What is, however, indisputable, is that Anaxagoras’ view of the physically basic
constituted a radical departure from that of Empedocles (and a fortiori from that
of his Ionian predecessors); that divergence, moreover, marked a fundamental
innovation in the conception of physical reality and of the relation between
reality and appearance.
For Anaxagoras’ account of what is physically basic we may begin with
fragments 1 and 4. Fragment 1, according to Simplicius the opening sentence of
Anaxagoras’ book, describes the original state of the universe, in which
everything that there is was so mixed up together that nothing was
distinguishable from anything else. What these things were fragment 4 tells us;
they were ‘the wet and the dry and the hot and the cold and the bright and the
dark and a lot of earth in with them and an infinite number of seeds, all unlike
one another’. In this list we see: first a list of the traditional opposite qualities, as
in Anaximander for example; second, earth, one of Empedocles’ four elements;
and third, an infinite number of seeds. ‘Seeds’ is a biological term, denoting
roughly what we would call the genetic constituents of organisms; the seed of a
kind of plant or animal is what develops into a new instance of that plant or animal
type, and, as Vlastos [6.19] points out, the process was ordinarily conceived as
one in which the seed, seen as ‘a compound of all the essential constituents of the
parent body from which it comes and of the new organism into which it will
grow’ (p. 464), develops by assimilating more of the same kinds of constituent
supplied by the environment. That these constituents were identified by
Anaxagoras with the organic stuffs, flesh, blood, fibre, etc., which compose
organisms of different kinds, is suggested by fragment 10: ‘How could hair come
to be from what is not hair, and flesh from what is not flesh?’ For the naked
embryo to develop into the hirsute adult, the seed must have contained hair, the
presumably minute quantity of which was supplemented by the amounts of hair
contained in the nourishment which the growing animal assimilated.
In Anaxagoras’ primeval mixture, then, we find qualities, namely the
opposites, and stuffs mingled together without any categorial distinction. The
stuffs include the four Empedoclean elements; earth is mentioned in fragment 4,
and air and aithēr, the bright upper atmosphere, (traditionally conceived as a
form of fire) in fragment 1, while the principle of fragment 10 (‘F cannot come
to be from what is not F’) implies that water is a constituent in the mixture too.
But the elements have no special status relative to other stuffs; earth is no more
primitive than bone or flesh (contrast Empedocles frs 96 and 98). In fact the
central and most novel feature of Anaxagoras’ world-picture is that it contains no
elemental stuffs. Relative to substances such as trees or fish, and to their parts,
such as leaves and fins, all stuffs are elemental, since substances come to be
through rearrangment of stuffs. But relative to other stuffs, no stuffs are
elemental, since every stuff is a component of every stuff; ‘so everything is in
everything, nor is it possible for them to be apart, but everything has a share in
everything’ (fr. 6), ‘in everything there is a share of everything, except mind’ (fr.
11).
Some interpreters (Cornford [6.5], Vlastos [6.19]), finding a literal reading of
these statements intolerably uneconomical, have urged a restricted reference for
the second occurrence of ‘everything’, interpreting ‘in everything there is a share
of everything’ as ‘in every substance there is a share of every opposite’. On this
view the basic items of Anaxagoras’ ontology are the opposites, stuffs such as
flesh and earth being ‘reduced’ to clusters of (opposite) qualities as in Berkeley
and Hume. (Schofield even describes stuffs as ‘logical constructions’ of opposites
([6.17], 133).) The texts in which these statements occur contain no hint of any
such programme. They give no justification for restricting the reference of
‘everything’ more narrowly than to the ‘all things’ which were together in the
original mixture, which undoubtedly include the stuffs air and aithēr (fr. 1) and
on the most natural reading earth and an infinite number of seeds (fr. 4).
Moreover, the idea that qualities are ontologically more basic than stuffs also
lacks support from the fragments. Those, to repeat, present the picture of the
original state of things as a mixture of constituents of all kinds, every one of
which is equally a constituent, not only of the mixture, but of every other
constituent. Further, they attest that the ‘everything in everything’ principle
holds in the present world order as much as it did in the original state (fr. 6). Can
sense be made of these claims on the generous interpretation of ‘everything’
which is here adopted?
Before proceeding to that question we should consider another restriction on
the generality of ‘everything’ proposed by Cornford [6.5]. Observing correctly
that the concept of seed is a biological one and that the biological processes of
nutrition and development are particularly prominent in the fragments and
testimonia, Cornford restricts the ‘everything in everything’ principle to organic
substances, interpreting it as ‘in every organic substance there are seeds of every
organic substance’. While the indefinite variety of observable biological
transformations provides grounds for accepting that every organic substance can
come from every other, and must therefore (by the principle that F cannot come
from what is not F) be a constituent of every other, there is no ground to extend
this to non-organic substances. To use his example ([2.15], 280), since we never
observe acorns turn into emeralds, there is no reason why Anaxagoras should
have believed that acorns contain portions of emerald. On the other hand,
Aristotle reports (Physics 203a23–4, DK 59 A 45) that Anaxagoras held that
every part is a mixture in the same way as the whole (i.e. the universe) because
he saw that anything comes to be from anything, and Lucretius cites the coming
to be of gold, earth and other non-organic stuffs along with, and explained by the
same process as, organic generation (I.830–42, DK 59 A 44). The
comprehensive character of traditional Ionian explanation makes it plausible that
Anaxagoras should have accepted the universal thesis. Xenophanes had already
noticed the transformation of animals and plants into stone by fossilization (DK
21 A 33), and the transformations of stone into earth and earth into water by
erosion, of water to wine, wine to animal tissue, etc. were matters of common
observation (see Simplicius’ commentary on the passage from the Physics cited
above (DK 59 A 45)). It is therefore highly plausible that Anaxagoras should
have held that we can have no reason to say of any two things that they cannot be
transformed into one another by some chain of causation, however long. We
know that the atomists, following Parmenides, appealed to the Principle of
Sufficient Reason, arguing, for example, that since there was no more reason for
atoms to have one shape rather than another, and since they obviously had some
shapes, therefore they must have all possible shapes (Simplicius, Physics 28.9–
10). Similarly, Anaxagoras may have reasoned that since some transformations
are observed to occur, and there is no reason for one transformation to occur
rather than another, all transformations must be assumed to occur.
I shall take it, then (1) that Anaxagoras drew no systematic distinction between
stuffs and qualities and (2) that he believed that every amount or bit of any stuff
(or quality) contains quantities or bits of every other stuff (or quality). On the
assumption that if a given amount of a given stuff (amount A of stuff S) contains
amounts B, C, D…of stuffs X, Y, Z…then A is larger than B, and larger than C
and larger than D etc.,…it immediately follows that there is no smallest quantity
of any stuff. For any quantity of any stuff, however small, contains smaller
quantities of every stuff, and so on ad infinitum. Anaxagoras asserted this
conclusion explicitly: ‘for there is no smallest part of what is small, but always a
smaller’ (fr. 3), and according to Simplicius deduced it from the premiss that
everything is in everything and is separated out from everything.
But if there is a portion of every stuff in every stuff, what distinguishes one
stuff from another? Anaxagoras’ answer is given at the end of fragment 12;
‘Nothing is like anything else, but each single thing most clearly is and was that
of which it contains most’. This dark saying is explained by Aristotle in Physics
187b1–7 (not in DK):
Therefore they say that everything is mixed in everything, because they
saw everything coming into being from everything. And they appeared
different and were called by different names from one another on account
of the quantitatively predominant component in the mixture of infinitely
many components; for there is nothing which is as a whole pure white or
black or sweet or flesh or bone, but the component each thing has most of,
that is what the nature of the thing appears to be.
That is to say, every stuff contains amounts of every stuff, but in different
proportions, and in each stuff the component of which there is the largest amount
gives its character and name to the whole. Thus a lump of earth contains, in
addition to earth, ‘seeds’ of every other stuff and quality, but it contains more
earth than any of the others (the other ‘seeds’ may be thought of as impurities in
the sample of earth). So any sample of earth is not pure earth, but predominantly
earth; in general, to be a sample of S is to be predominantly S. (The texts leave it
indeterminate whether something predominantly S must contain more S than all
other components put together, or merely more S than any other component; I
shall assume that the weaker condition is sufficient.)
This doctrine may seem to threaten Anaxagoras with a dilemma. Either it
commits him to the existence of samples of pure S, which is inconsistent with the
doctrine that everything contains a bit of everything, or it is empty. Taking the
first horn, it is clear what it means to say that a sample of S is predominantly S.
Analyse the original sample, by whatever physical process is available, into its
components S, A, B, C… Continue the analysis until you reach pure samples of
each component. Then you will discover that the amount of pure S is larger than
the amount of pure A, larger than the amount of pure B, etc. But now it is false that
everything contains a bit of everything; analysis will have succeeded in doing
what Anaxagoras explicitly says (fr. 8) it is impossible to do, namely separate
from one another the things in the cosmos ‘and chop them off with an axe’.
Prima facie Anaxagoras should prefer the other horn. According to this there are
no pure samples of any stuff; every sample of every stuff, however small, will
contain as impurities amounts of every other stuff. But now what does it mean to
say that gold contains more gold than hot, sweet, blood, vegetable fibre…? It
can’t mean that it contains more pure gold than pure hot…since there are no such
pure stuffs. It means that it contains more gold than hot etc., i.e. more stuff that
contains more gold than hot etc., and the stuff that that stuff contains more of is
the stuff that contains more gold etc., and so on for ever. That is to say, we can
never give a complete specification of what it is that gold contains most of; gold
just is what contains more gold than anything else, and so on for ever. In
semantic terms, we have no account of what F means if all we can say is ‘“A is F”
means “A is predominantly F”’.
But in order to understand the name of a stuff it is not necessary that it should
be possible, even in principle, to isolate pure samples of that stuff. As Kripke1 has
shown, the names of stuffs are proper names whose reference is fixed by those
observable properties which typically, though contingently, characterize that
stuff. Thus gold is that stuff, whatever it is, which is yellow, shiny, malleable,
etc. The specification of what stuff it is which has those properties is the task of
the best available theory, in modern terms the theory of elements, which
identifies gold as the element with atomic number 79. The only resource
available to Anaxagoras to identify stuffs is via their constitution; thus gold just
is that stuff which when analysed yields more samples of yellow, shiny,
malleable stuff than red, warm, sticky, liquid stuff (and so on for every stuff-
description). Analysis goes on for ever, in principle at least; even when the
technical limit is reached of whatever process of physical separation has been
employed, we know a priori that every sample of yellow, shiny, malleable stuff
contains infinitely many samples of every kind of stuff, but always more of
yellow, shiny, malleable stuff than of any other.
An objection to the attribution of this theory to Anaxagoras is that it seems
flatly to contradict Aristotle’s evidence (DK 59 A 43, 45, 46) that in
Anaxagoras’ system the elements were ‘the homoeomerous things’. In
Aristotelian terminology a homoeomerous substance is one whose parts are of
the same nature as the whole, e.g. every part of a piece of flesh is a piece of flesh,
as opposed for example to a plant, whose parts are leaves, roots etc., not plants.
In general, stuffs, which we have seen to be among Anaxagoras’ basic things, are
in Aristotelian terms homoeomerous. Hence Anaxagoras is committed to holding
that every part of a piece of gold is a piece of gold, which contradicts the account
given above, according to which a piece of gold contains, in addition to pieces of
gold, portions of every other substance and quality. (This contradiction is the
basis of Cornford’s interpretation of ‘everything in everything’ as ‘every
opposite in every substance’.) This difficulty seems to me illusory. One
possibility (adopted by McKirahan [2.7], 208, n. 38) is that in identifying
Anaxagoras’ basic substances as ‘the homoeomerous things’ Aristotle means
merely to identify them as stuffs, i.e. the things which in Aristotle’s theory are
homoeomerous, without attributing to Anaxagoras the thesis that those stuffs are
in fact homoeomerous. This may well be right. It is, however, possible that
Anaxagoras may have maintained (the texts are silent) that stuffs and qualities
are indeed homoeomerous, despite containing portions of every stuff and quality.
He could do so consistently if by ‘homoeomerous’ he meant ‘having every part of
the same kind as the whole’, and if by part he understood what is produced by
division. He might then have maintained that however minutely one divided up a
lump of gold, what would be produced would be fragments of gold, the other
stuffs and qualities being separable, if at all, not by division, but by other
processes such as smelting. That would be, in effect, to distinguish parts, separable
by division, from portions, separable, if at all, otherwise than by division. (It is
not necessary for this hypothesis to suppose that Anaxagoras marked that
distinction by any explicit distinction of terminology.) I emphasize that this
suggestion is offered merely as a possibility, and that I am not maintaining that it
has positive textual support. The crucial point is that the interpretation of the
‘everything, in everything’ doctrine which I have defended above is not
inconsistent with Aristotle’s statements that Anaxagoras’ basic things were
homoeomerous.
That doctrine is neither empty nor viciously regressive; it is an ingenious
construction which allows Anaxagoras to maintain consistently two of his
fundamental theses: (1) there is a portion of every stuff in every stuff, (2) each
stuff is characterized by the character of its predominant portion. Its crucial flaw
is its lack of explanatory force; the character of a stuff is ‘explained’ by its
principal component’s having precisely that character, which is in turn
‘explained’ by its principal component’s having precisely that character, and so
on ad infinitum. A central element in explanation, the simplification of a wide
range of diverse phenomena via laws connecting those phenomena with a small
range of basic properties, is absent. Nor is this an oversight, since the effect of
the principle ‘What is F cannot come from what is not F’ is precisely to exclude
the possibility that the ‘explanation’ of something’s having a property should not
contain that very property in the explanans. The slogan ‘Appearances are the
sight of what is non-apparent’ (fr. 21a) thus proves to state a central, and quite
startling, Anaxagorean doctrine. At first sight it appears to state the empiricist
axiom that theories about what is unobserved must be based on observation, and
it was presumably in that sense that Democritus is said by Simplicius to have
approved it. But in fact Anaxagoras’ claim is much stronger; he is asserting that
the observable phenomena literally do give us sight of what is unobserved, in
that the very properties which we observe characterize the world through and
through. (This was presumably the point of the remark of Anaxagoras to his
associates recorded by Aristotle (Metaphysics 1009b26–8, DK 59 A 28), that
they would find that things are just as they supposed.) This does not contradict
fragment 21, where Anaxagoras is reported by Sextus as declaring that the
weakness of the senses prevents us from judging the truth, and as supporting this
claim by citing the imperceptibility of the change produced by pouring a
pigment drop by drop into a pigment of a different colour. Rather, the two
fragments complement one another. The senses are unable to discern the infinite
variety of components in any observable thing, and hence to detect in them the
microscopic rearrangements whose accumulation eventually produces an
observable change (fr. 21); yet the nature of those components has to be what is
revealed by observation at the macroscopic level (fr. 21a).
Just as there are in Anaxagoras’ theory no elements, i.e. basic stuffs, so there are
no basic properties. It cannot, therefore, be the task of theory to devise an account
of the world sufficient to explain the phenomena, since the phenomena must
ultimately be self-explanatory. Theory has, however, the more limited task of
explaining how the observed world has come to be in the state in which it is; this
brings us to another central Anaxagorean concept, that of Mind.
Mind
In the famous passage of the Phaedo cited above, in which Socrates describes his
intellectual progress, he states that he was dissatisfied by the absence of
teleleogical explanation from the theories of the early philosophers. Anaxagoras
promised to make good this deficiency, since he claimed that the world is
organized by Mind. Socrates, assuming that this organization by a cosmic
intelligence must aim at the best possible state of things, eagerly perused
Anaxagoras’ book for an account of that state and how it was attained, and was
all the more disappointed to discover that in his cosmology Anaxagoras made no
use of teleology, remaining content, like his predecessors, with purely
mechanistic explanations.
The evidence of the fragments of Anaxagoras’ views on Mind is consistent
with this passage. The most important piece of evidence is fragment 12, which
contains a number of theses about the nature and activity of Mind, as follows:
Nature Mind is (a) unlimited
(b) self-directing
(c) separate from everything else
(d) the finest and purest of all
things
(e) all alike, the greater and the
less
Activity Mind (f) takes thought for everything
and has the greatest power
(g) controls everything which
has a soul
(h) directed the entire cosmic
rotation, initiating it and
continuing it
(i) knew all the mixtures and
separations of everything
(j) organized whatever was, is
and will be.
The first problem is, what is the reference of Anaxagoras’ term Nous? Is it mind
in general, instanced in different individual minds (as in ‘the concept of mind’),
or a single cosmic mind? The answer is that it is probably both. The specification
of mind given by (a)–(e) seems to be an attempt to differentiate mind as a
constituent of the universe from all other constituents. Mind is the finest and
purest of all things, it is self-directing (as opposed to other things, which
(according to (f), (g) and (j) are directed by mind), and it (alone) is separate from
everything else, whereas everything else contains a portion of everything else.
(Compare fr. 11, ‘In everything there is a portion of everything except mind, but
there are also some things which contain mind.’) But the account of mind’s
activity, most especially (h), strongly suggests the activity of a single supreme
mind, which organizes the cosmos as a whole. It is clear, too, that that is how Plato
represents Socrates as understanding Anaxagoras, especially Phaedo 97c: ‘Mind
is what organizes and is the cause of everything…the mind which organizes
everything will organize and arrange each thing as is best’. The characteristics
listed in (a)–(e) are characteristics of all minds, both ‘the greater and the less’
(i.e. presumably the supreme cosmic mind and subordinate minds, including but
not necessarily restricted to human minds), which are explicitly stated in (e) all
to be alike. The activities listed in (f)–(j) are activities of the cosmic mind,
though (g) may also perhaps refer to an individual mind directing each ensouled
thing, doubtless under the overall direction of the cosmic mind. (Aristotle says
(On the Soul 2–4, DK 59 A 100) that Anaxagoras sometimes identified soul
with mind and attributed the latter to all animals, but appears unsure of what
precisely he meant, while the pseudo-Aristotelian work On Plants reports that he
regarded plants as a kind of animals and attributed consciousness and thought to
them (815a15ff., DK 59 A 117).) Assuming that the fragments refer both to the
cosmic mind and to individual minds, they are inexplicit as to the relation
between the former and the latter. The minds of humans and of other animals are
clearly subordinate to the cosmic mind, but it is unclear what the model of
subordination is, i.e. whether particular human and other minds are parts of the
cosmic mind, or agents operating under its direction.
The only assertion which Anaxagoras supports by any argument is (c): mind
cannot be a constituent of any stuff, for if it were it would (by the ‘everything in
everything’ principle) be a constituent of every stuff. Why should it not be?
Empedocles had maintained that ‘everything has intelligence and a share in
thought’ (fr. 110); why should Anaxagoras have demurred? The reason which he
gives in fragment 12 is that if mind were a constituent of anything, the other
constituents would prevent it from exercising its directive function. Mind has to
be external to what it controls, as the rider has to be external to the horse. It is
hard to see any force in this argument. We think of organisms as self-directing,
and assume that some part of the organism functions as a control mechanism.
Why should the mind of a human or animal not be a built-in control mechanism
for the animal, or the cosmic mind such a mechanism for the cosmos as a whole?
It is problematic precisely because what is implied by the description of mind
as unlimited. All stuffs exist eternally (fragment 17), and are therefore
temporally boundless, and are unlimited in amount (fragments 1 and 3). Perhaps
(a) is simply to be read as making the same claims for mind, but the opening of
the fragment appears to contrast mind with the other things, and it is at least
tempting to look for a sense of ‘unlimited’ (apeiron) in which mind alone is
unlimited. Such a sense may be suggested by fragment 14, which states that mind
is where all the other things are. Mind is not, as we have seen, a constituent of
anything else, but it knows and controls everything, and is here said to be where
everything else is. The picture seems to be of mind as everywhere, pervading
everything without being part of anything. This would differentiate mind from
the other stuffs, for though every stuff is contained in every stuff, there are some
places where it is not, namely those places which are occupied by other stuffs.
Mind, on the other hand, if this suggestion is right, is not excluded from any
place by the presence of any stuff in that place. This, together with the
description of mind as the finest and purest of all things, may suggest that
Anaxagoras was groping towards the conception of mind as immaterial, but it
would be anachronistic to suggest that that conception is clearly articulated in the
fragments.
The fragments provide scant information on how the cosmic mind directs and
organizes the cosmos. Fragment 12, supplemented by some secondary sources
(DK 59 A 12 (Plutarch), 42 (Hippolytus) and 71 (Aetius)), indicates that a
cosmic rotation separated out the original undifferentiated mass by centrifugal
force into the main elemental masses, and also attests that the original rotation is
continuing and will continue to a greater and greater extent. But what the
connection is between the rotation and other kinds of natural change, e.g. the
generation and development of plants and animals, and how mind is supposed to
organize the latter, remains obscure. In particular, our extant evidence,
consistently with Socrates’ complaint in the Phaedo (see above) says nothing
about how natural change, of whatever kind, is directed towards the best.
It is none the less likely that Anaxagoras held the cosmic mind to be divine.
The explicit statements to this effect in ps.-Plutarch’s Epitome and in Stobaeus
(DK 59 A 48) are not confirmed by similar assertions in the fragments.
However, the description of its activity in fragment 12, as ‘taking thought for
everything and having the greatest power’, ‘controlling’ (kratein) everything
ensouled and the whole cosmic rotation, ‘knowing everything that is mixed
together and separated out’ and ‘organizing’ (diakosmein) everything is
irresistibly suggestive not only of traditional divinities such as Zeus but also of
the cosmic divinities of Anaxagoras’ philosophical predecessors, the divine mind
of Xenophanes which ‘without labour controls all things by the thought of its
mind’ (DK 21 B 25, cf. 26) and the holy mind of Empedocles ‘darting through
the whole cosmos with swift thoughts’ (DK 31 B 134).2
In this respect, as in many of the details of his astronomy and cosmology,
Anaxagoras preserves some of the features of earlier Ionian thought. The
conventional picture of him as a child of the fifth-century enlightenment is to
that extent one-sided, yet it is not altogether inaccurate. In fact the two aspects
are complementary; Anaxagoras represents in a striking way the vitality of the
Ionian tradition, specifically its adaptability to the rigour of Eleatic thought and
to the critical spirit of the later fifth century. That feature is, if anything, even more
pronounced in the thought of the atomists, especially that of Anaxagoras’
younger contemporary Democritus.
THE ATOMISTS
Atomism was the creation of two thinkers, Leucippus and Democritus. The
former, attested by Aristotle, our primary source, as the founder of the theory,
was a shadowy figure even in antiquity, being over-shadowed by his more
celebrated successor Democritus to such an extent that the theory came to be
generally regarded as the work of the latter, while Epicurus, who developed and
popularized atomism in the third century BC, went so far as to deny that
Leucippus ever existed. Nothing is known of his life. Even his birthplace was
disputed, some sources associating him with one or other of the two main centres
of early Greek philosophy, Miletus and Elea, others with Abdera, the birthplace
of Democritus. Of his dates all that can be said is that since he was certainly older
than Democritus he lived during the fifth century. No lists of his works survive,
and only a single quotation is ascribed to him by a single ancient source
(Stobaeus).
Only a little more is known about Democritus. He came from Abdera, on the
north coast of the Aegean (also the birthplace of Protagoras), and is reported as
having described himself as young in the old age of Anaxagoras, i.e. probably in
the 430s. He is traditionally said to have lived to a very great age (over 100 years
on some accounts), and may therefore be supposed to have lived from about the
middle of the fifth till well into the fourth century (though some scholars dispute
the accounts of his longevity). He is quoted as saying that he visited Athens
(where no one knew him), and is said to have had some slight acquaintance with
Socrates. Of his works, which according to the list preserved in Diogenes
Laertius’ Life were many and encyclopaedic in scope, including a complete
account of the physical universe and works on subjects including astronomy,
mathematics, literature, epistemology and ethics, none survive. Ancient sources
preserve almost 300 purported quotations, the great majority on ethics (see
below), but also including some important fragments on epistemology preserved
by Sextus. Our knowledge of the metaphysical foundations and physical
doctrines of atomism relies on the doxographical tradition originating from
Aristotle, who discusses atomism extensively. The precise relation between
Leucippus and Democritus is unclear. Aristotle and his followers treat Leucippus
as the founder of the theory, but also assign its basic principles to both Leucippus
and Democritus; later sources tend to treat the theory as the work of Democritus
alone. While it is clear that the theory originated with Leucippus it is possible
that the two collaborated to some extent, and almost certain that Democritus
developed the theory into a universal system.
Physical Principles
According to Aristotle, the atomists, like Anaxagoras, attempted to reconcile the
observable data of plurality, motion and change with the Eleatic denial of the
possibility of coming to be or ceasing to be. Again like him, they postulated
unchangeable primary things, and explained apparent generation and corruption
by the coming together and separation of those things. But their conceptions of
the primary things and processes differed radically from those of Anaxagoras.
For the latter the primary things were observable stuffs and properties, and the
primary processes mixing and separation of those ‘elements’. For the atomists,
by contrast, the primary things were not properties and stuffs but physical
individuals, and the primary processes not mixing and separation but the
formation and dissolution of aggregates of those individuals. Again, the basic
individuals were unobservable, in contrast with the observable stuffs of
Anaxagoras; consequently their properties could not be observed, but had to be
assigned to those individuals by theory.
Since the theory had to account for an assumed infinity of phenomena, it
assumed an infinite number of primary substances, while postulating the
minimum range of explanatory properties, specifically shape, size, spatial
ordering and orientation within a given ordering. All observable bodies are
aggregates of basic substances, which must therefore be too small to be
perceived. These corpuscles are physically indivisible (atomon, literally
‘uncuttable’), not merely in fact but in principle; Aristotle reports an (unsound)
atomistic argument, which has some affinities with one of Zeno’s arguments
against plurality, that if. (as for example Anaxagoras maintained) it were
theoretically possible to divide a material thing ad infinitum, the division must
reduce the thing to nothing. This Zenonian argument was supported by another
for the same conclusion; atoms are theoretically indivisible because they contain
no void. On this conception bodies split along their interstices; hence where there
are no interstices, as in an atom, no splitting is possible. (The same principle
accounts for the immunity of the atoms to other kinds of change, such as
reshaping, compression and expansion; all require displacement of matter within
an atom, which is impossible without any gaps to receive the displaced matter.)
It is tempting to connect the assumption that bodies split only along their
interstices with the Principle of Sufficient Reason, which the atomists appealed
to as a fundamental principle of explanation (arguing for example that the
number of atomic shapes must be infinite, because there is no more reason for an
atom to have one shape than another (Simplicius, Physics 28.9–10, DK 67 A 8)).
Given the total uniformity of an atom, they may have thought, there could be no
reason why it should split at any point, or in any direction, rather than any other.
Hence by the Principle of Sufficient Reason, it could not split at all.
Atoms are in a state of eternal motion in empty space; the motion is not the
product of design, but is determined by an infinite series of prior atomic
interactions (whence two of Aristotle’s principle criticisms of Democritus, that
he eliminated final causation and made all atomic motion ‘unnatural’). Empty
space was postulated as required for motion, but was characterized as ‘what is not’,
thus violating the Eleatic principle that what is not cannot be. We have no
evidence of how the atomists met the accusation of outright self-contradiction.
As well as explaining the possibility of motion, the void was postulated to
account for the observed plurality of things, since the atomists followed
Parmenides (fragment 8, 22–5) in maintaining that there could not be many
things if there were no void to separate them. The theoretical role of the void in
accounting for the separation of atoms from one another has an interesting
implication, recorded by Philoponus (Physics 494.19–25 (not in DK), On
Generation and Corruption 158.26–159.7, DK 67 A 7). Since atoms are
separated from one another by the void, they can never strictly speaking come
into contact with one another. For if they did, even momentarily, there would be
nothing separating them from one another. But then they would be as inseparable
from one another as the inseparable parts of a single atom, whose indivisibility is
attributed to the lack of void in it (see above); indeed, the two former atoms
would now be parts of a single larger atom. But, the atomists held, it is
impossible that two things should become one. Holding atomic fusion to be
theoretically impossible, and taking it that any case of contact between atoms
would be a case of fusion (since only the intervening void prevents fusion), they
perhaps drew the conclusion that contact itself is theoretically impossible. Hence
what appears to be impact is in fact action at an extremely short distance; rather
than actually banging into one another, atoms have to be conceived as repelling
one another by some sort of force transmitted through the void. Again, though no
source directly attests this, the interlocking of atoms which is the fundamental
principle of the formation of aggregates is not strictly speaking interlocking,
since the principle of no contact between atoms forbids interlocking as much as
impact. Just as impact has to be reconstrued as something like magnetic
repulsion, so interlocking has to be reconstrued as quasi-magnetic attraction. If
this suggestion is correct (and it is fair to point out that no ancient source other
than Philoponus supports it) it is a striking fact that, whereas the post-
Renaissance corpuscular philosophy which developed from Greek atomism
tended to take the impossibility of action at a distance as an axiom, the original
form of the theory contained the a priori thesis that all action is action at a
distance; consequently that impact, so far from giving us our most fundamental
conception of physical interaction, is itself a mere appearance which disappears
from the world when the description of reality is pursued with full rigour.
Chance and Necessity
While the broad outlines of the views of the atomists on these topics can be fairly
readily reconstructed, there is much obscurity about the details. The atomists’
universe is purposeless, mechanistic and deterministic; every event has a cause,
and causes necessitate their effects. Broadly speaking the process is mechanical;
ultimately, everything in the world happens as a result of atomic interaction. The
process of atomic interaction has neither beginning nor end, and any particular
stage of that process is causally necessitated by a preceding stage. But exactly
how the atomists saw the process as operating is obscure. This obscurity is
largely attributable to the fragmentary nature of the evidence which we possess,
but it may be that the statement of the theory itself was not altogether free from
obscurity.
The fundamental text is the single fragment of Leucippus (DK 67 B 1):
‘Nothing happens at random, but everything from reason and by necessity.’ The
denial that anything happens ‘at random’ (matēn) might well be taken in
isolation to amount to an assertion that all natural events are purposive, since the
adverb and its cognates frequently have the sense ‘in vain’ (i.e. not in accordance
with one’s purpose) or ‘pointlessly’. If that were the sense of ‘not matēn’ then
‘from reason’ (ek logou) would most naturally be understood as ‘for a purpose’.
These renderings are, however, very unlikely. The majority of the sources follow
Aristotle (On the Generation of Animals 789b 2–3, DK 68 A 66) in asserting that
Democritus denied purposiveness in the natural world, explaining everything by
mechanistic ‘necessity’.3 A reading of Leucippus which has him assert, not
merely (contra Democritus) that some, but that all natural events are purposive,
posits a dislocation between the fundamental world-views of the two of such
magnitude that we should expect it to have left some trace in the tradition.
Moreover, the attribution of all events to necessity, a central feature of the
mechanistic Democritean world-view, is itself attested in the fragment of
Leucippus. We ought, then, to look for an interpretation of the fragment which
allows it to be consistent with Democritus’ denial of final causation.
Such an interpretation is available without forcing the texts. Sometimes (e.g.
Herodotus VII.103.2, Plato Theaetetus 189d) matēn is to be rendered not ‘without
purpose’ but ‘without reason’ (‘in vain’ and ‘empty’ have similar ranges of
application). Given that construal of matēn, ‘from reason’ is to be construed as
‘for a reason’, where the conception of reason is linked to that of rational
explanation. The first part of the fragment (‘Nothing happens at random, but
everything from reason’) thus asserts, not universal purposiveness in nature, but
a principle which we have already seen to be pervasive in atomism, the Principle
of Sufficient Reason. Instead of a radical discontinuity between Leucippus and
Democritus, the fragment, thus construed, attests commitment to a principle
basic to atomism. The second half (‘and by necessity’) makes a stronger claim,
which links the notion of rational explanation to the notions of necessity and of
cause. The stronger claim is that whatever happens has to be happen, cannot but
happen. This amounts to a specification of the reason whose existence is asserted
in the first half of the sentence; nothing happens without a reason, and, in the
case of everything which happens, the reason for which it happened was that it
had to happen. But the claim that whatever happens happens ‘by necessity’ is not
just the claim that whatever happens has to happen, though the former implies
the latter. For the concept of necessity is not a purely modal concept requiring
elucidation via its connection with other such concepts, such as possibility and
impossibility. Rather, necessity is conceived as an irresistible force bringing it
about that things have to happen. This is indicated both by the causal force of the
preposition hypo (rendered ‘by’ in the expression ‘by necessity’), and also by the
fact that Democritus is reported as identifying necessity with impact and motion
((Aetius I.26.2, DK 68 A 66) on the interpretation of this see below). Impact and
motion, then, take over the determining role traditionally assigned to Necessity,
when the latter is conceived (as in Parmenides and Empedocles) as an
ineluctable, divine cosmic force (cf. Plato, Protagoras 345d5 ‘Against necessity
not even the gods fight’).
Nothing, then, just happens; every event occurs because it had to occur, i.e.
because it was made to occur by prior impact (namely, of atoms on one another)
and prior motion (namely, of atoms). So there can be no chance events, i.e. no
events which simply happen. On the other hand, we have evidence that the
atomists assigned some role to chance in the causation of events, though
precisely what role is not easy to determine. Aristotle (Physics 196a24–8, DK 68
A 69), Simplicius (Physics 327.24–6, DK 68 A 67; 330.14–20, DK 68 A 68) and
Themistius (Physics 49.13–16 (not in DK)) all say that Democritus attributed the
formation of every primal cosmic swirl to chance (indeed Aristotle finds a special
absurdity in the theory that while events in a cosmos occur in regular causal
sequences, the cosmos itself comes into being purely by chance). Cicero (On the
Nature of the Gods I.24.66, DK 67 A 11) says that heaven and earth come into
existence ‘without any compulsion of nature, but by their [i.e. the atoms’] chance
concurrence’, while Lactantius (Divine Institutions I.2.1–2, DK 68 A 70) baldly
attributes to Democritus and Epicurus the view that ‘everything happens or
comes about fortuitously’. Aetius I.29.7: ‘Democritus and the Stoics say that it
[i.e. chance] is a cause which is unclear to human reason’ may be read either as
asserting or as denying that Democritus believed that there are genuinely chance
events. Read in the latter way it attributes to Democritus the view that we explain
an event as due to chance when its real cause is unknown; on the former reading
the view attributed to Democritus is that chance is itself a real cause of events,
but an unfathomable one (the position mentioned by Aristotle without attribution
at Physics 19605–7). A passage from Epicurus’ On Nature (fr. 34.30 in
Arrighetti), which one might hope to be our most authoritative source, is
similarly ambiguous. There Epicurus describes the atomists as ‘making necessity
and chance responsible for everything’, a formulation which is ambiguous
between two positions; (1) ‘necessity’ and ‘chance’ are two names for a single
universal cause, (2) necessity and chance are distinct but jointly exhaustive
causes of everything.4
The passage of Lactantius is of little weight; he states that the fundamental
question is whether the world is governed by providence or whether everything
happens by chance, and says that Epicurus and Democritus held the latter view. It
is plausible that he took their denial of providence to commit them to that view,
since he himself took those alternatives to be exhaustive. This passage, then,
gives no independent ground for the attribution to either philosopher of the thesis
that literally everything happens by chance.
We are still, however, left with those passages attesting Democritus’ belief that
every cosmic swirl, and therefore every cosmos, come into being by chance.
That might be thought to be confirmed by the statement in Diogenes Laertius’
summary of Democritus’ cosmology that he identified the cosmic swirl itself
with necessity (IX.45, DK 68 A 1). On this interpretation the statement that
everything happens by necessity is confined to events within a cosmos, and
states that all such events are determined by the atomic motions constituting the
swirl. The swirl itself, however, is not determined by itself, nor by anything; it
just happens. Eusebius (Praeparatio Evangelica XIV.23.2, DK 68 A 43) also
reports Democritus as ascribing the formation of worlds to chance, and goes
further by reporting him as holding that the pre-cosmic motion of the atoms was
also random (‘these atoms travel in the void hōs etuchen (literally “as it
chanced”). On this view necessity governs, but is local to, a world order, which
itself arises by chance from a pre-cosmic state where there is no necessity.
The recognition of pure chance is, however, inconsistent with the Principle of
Sufficient Reason, which we know the atomists accepted. It therefore seems
preferable to look for some interpretation of the evidence which is consistent
with that principle. That interpretation is provided by the first reading of the
Aetius passage cited above, namely that the ascription of events to chance is a
confession of ignorance of their causes, not a denial that they have causes. Some
features of the evidence support this suggestion. Diogenes’ summary of the
cosmology of Leucippus (IX.30–3, DK 67 A 1) concludes with the sentence,
‘Just like the coming into being of worlds, so do their growth, decay, and
destruction occur according to a certain necessity, the nature of which he does not
explain.’ In line with his famous dictum, then, Leucippus held that all events
including the formation of worlds happen according to necessity, but was unable
to say what it is that necessitates cosmic events. It is then plausible that either he
himself or Democritus said that such events may be said to occur by chance, in
the sense that we are (whether merely in fact or in principle is indeterminate)
ignorant of their causes. Simplicius’ evidence suggests just that; in Physics 327.
24–6 his attribution to Democritus of the view that the cosmic swirl arises by
chance is avowedly his own inference from the fact that Democritus did not say
how or why that occurs. In Physics 330.14–20 he says that although Democritus
appeared (edokei) to have made use of chance in his account of the formation of
worlds, in his more detailed discussions (en tois merikōterois) he says that
chance is not the cause of anything. That suggests that he merely seemed to
ascribe cosmogony to chance (perhaps by speaking of it as a chance occurrence
in the sense of an occurrence whose cause is unknown). Explanations of specific
kinds of events and of particular events were governed by the principle that there
are no chance events, but no attempt was made to offer explanations of the
fundamental cosmic processes themselves. That need not imply that they are
literally uncaused, but that they might as well be treated as such, since their
actual causes are of a degree of complexity outstripping the powers of the human
mind to discover.
For the atomists, then, everything happens of necessity; the identification of
necessity with the mechanical forces of impact and motion may have been due to
Democritus. But what exactly was his view on this? Aetius (I.26.2, DK 68 A 66)
reports him as identifying necessity with ‘impact and motion and a blow of
matter’. Are impact and motion given equal status in this identification, or is it
taken for granted that motion is always caused by prior impact? On the former
construal some motion may be either uncaused, or attributable to a cause other
than impact. In favour of the first alternative is Aristotle’s evidence (Physics
252a32–b2, DK 68 A 65) that Democritus held that one should not ask for a
cause of what is always the case. He might then have said that the atoms are
simply always in motion. But while that principle allows him to exclude the
question, ‘What causes the atoms to be in motion?’, the Principle of Sufficient
Reason requires that the question, ‘Why is any particular atom moving with any
particular motion?’ should have an answer, and it might appear inevitable that
that answer should refer to a prior atomic collision. We have, however, to recall
the evidence from Philoponus that atoms never actually collide or come into
contact, with its implication that the basic physical forces are attraction and
repulsion. Attraction, as we saw, explains, not atomic motion, but the immobility
of atoms relative to one another, since the relative stability of atoms in an
aggregate has to be explained, not by their literal interlocking, but by their being
held together as if interlocked by an attractive force operating over the tiny gaps
between the atoms in the aggregate. In addition, some form of attraction may
also have explained some atomic motions; Sextus cites Democritus (Adversus
Mathematicos VII.116–8, DK 68 B 164) as holding that things of the same kind
tend to congregate together, and as illustrating that phenomenon by examples of
the behaviour of animate (birds flocking together) and inanimate things (grains
of different sorts being separated out by the action of a sieve, pebbles of different
shapes being sorted together by the action of waves on a beach). That this
principle was applied to the atoms appears from Diogenes’ account of the
cosmogony of Leucippus, where atoms of all shapes form a swirling mass from
which they are then separated out ‘like to like’. The separation out of atoms of
different sizes could adequately be accounted for by the stronger centripetal
tendency of the larger, itself a function of their greater mass. But the context in
Diogenes, where the atoms have just been described as of all shapes, with no
mention so far of size, suggests that ‘like to like’ is here to be understood as ‘like
to like in shape’. Aetius’ report of Democritus’ account of sound (IV.19.3, DK
68 A 128) asserts that atoms of like shape congregate together, and contains the
same illustrative examples as the Sextus passage; it is plausible, though not
explicitly asserted, that this same principle accounts for the formation of
aggregates of spherical atoms, for example flames.
We have, then, evidence that Democritus’ dynamics postulated three
fundamental forces: a repulsive force which plays the role of impact in a
conventional corpuscular theory, and two kinds of attractive force, one of which
draws together atoms of the same shape and another which holds together atoms
of different shapes in an atomic aggregate. It is plausible that he applied the term
‘necessity’ to all three, regarding them alike as irresistible. It must, however, be
acknowledged first that the evidence for this theory is fragmentary and also that
even if it is accepted we have no idea whether or how Democritus attempted to
unify these forces into a unified theory. Stated thus baldly, the theory has
obvious difficulties; for example, if two atoms of the same shape collide, do they
rebound or stick together? If all atoms have both attractive and repulsive force
there must be some yet more basic principles determining what force or
combination of forces determines their motion. Our sources give no hint of
whether Democritus had so much as considered such questions.
Epistemology and Psychology
While we have no evidence to suggest that Leucippus was concerned with
epistemological questions, there is abundant evidence of their importance for
Democritus. It is quite likely that the latter’s epistemological interests were
stimulated at least in part by his fellow citizen and elder contemporary
Protagoras (see below). Our evidence is highly problematic, in that it provides
support for the attribution to Democritus of two diametrically opposed positions
on the reliability of the senses. On the one hand, we have a number of passages,
including some direct quotations, in which he is seen as rejecting the senses as
totally unreliable; on the other, a number of passages ascribe to him the doctrine
that all appearances are true, which aligns him with Protagorean subjectivism, a
position which he is, however, reported as having explicitly rejected. The former
interpretation is supported mainly by evidence from Sextus, and the latter mainly
by evidence from Aristotle and his commentators, but we cannot resolve the
question by simply setting aside one body of evidence in favour of the other. The
reasons are that: (1) in the course of a few lines (Metaphysics 1009b7–17, DK 68
A 112) Aristotle says both that Democritus says that either nothing is true, or it is
unclear to us, and that he asserts that what appears in perception is necessarily
true; (2) in Adversus Mathematicos (VII.136, DK 68 B 6) Sextus ascribes some
of Democritus’ condemnation of the senses to a work in which ‘he had
undertaken to give the senses control over belief. Prima facie, then, the evidence
suggests that both interpretations reflect aspects of Democritus’ thought. Was
that thought, then, totally inconsistent? Or can the appearance of systematic
contradiction be eliminated or at least mitigated?
The former interpretation is based on the atomists’ account of the secondary
qualities, whose observer-dependence Democritus seems to have been the first
philosopher to recognize. Our senses present the world to us as consisting of
things characterized by colour, sound, taste, smell, etc., but in reality the world
consists of atoms moving in the void, and neither atoms nor the void are
characterized by any secondary quality. We thus have a dichotomy between how
things seem to us and how they are in reality, expressed in the celebrated slogan
(fr. 9) ‘By convention sweet and by convention bitter, by convention hot, by
convention cold, by convention colour, but in reality atoms and the void.’
Further, the distinction between the reality of things and the appearances which
that reality presents has to be supplemented by an account of the causal
processes via which we receive those appearances. Atomic aggregates affect us
by emitting from their surfaces continuous streams of films of atoms which
impinge on our sense organs, and the resulting perceptual states are a function of
the interaction between those films and the atomic structure of the organs. For
example, for an object to be red is for it constantly to emit films of atoms of such
a nature that, when those films collide with an appropriately situated perceiver,
the object will look red to that perceiver.
Hence we are doubly distanced from reality; not only phenomenologically, in
that things appear differently from how they are, but also causally, in that we
perceive atomic aggregates via the physical intervention of other aggregates
(namely the atomic films) and the action of those latter on our sense organs. A
number of fragments stress the cognitive gulf which separates us from reality: (fr.
6) ‘By this principle man must know that he is removed from reality’; (fr. 8)
‘Yet it will be clear that to know how each thing is in reality is impossible’; (fr.
10) ‘That in reality we do not how each thing is or is not has been shown many
times’ and (fr. 117) ‘In reality we know nothing, for truth is in the depths.’
This evidence immediately presents a major problem of interpretation. On the
one hand fragment 9 and associated reports stress the gulf between appearance
and reality, claiming that the senses are unreliable in that they misrepresent
reality. That dogmatic claim presupposes that we have some form of access to
reality, which enables us to find the sensory picture unfaithful to how things are
in fact. On the other hand, fragments 6, 8, 10 and 117 make the much more
radical claim that reality is totally inaccessible, thereby undercutting the thesis
that there is a gulf between appearance and reality. Fragment 7, ‘This argument
too shows that in reality we know nothing about anything, but each person’s
opinion is something which flows in’ and the second half of fragment 9, ‘In fact
we know nothing firm, but what changes according to the condition of our body
and of the things that enter it and come up against it’ attempt uneasily to straddle
the two positions, since they draw the radically sceptical conclusion from a
premiss about the mechanism of perception which presupposes access to the
truth about that mechanism. We might conclude that Democritus simply failed to
distinguish the dogmatic claim that the senses misrepresent reality from the
sceptical claim that we can know nothing whatever about reality. An alternative
strategy is to look for a way of interpreting the evidence which will tend to bring
the two claims nearer to consonance with one another.
We can bring the two claims closer to one another if the ‘sceptical’ fragments
are interpreted as referring, not to cognitive states generally, but specifically to
states of sensory cognition. These fragments will then simply reiterate the thesis
that we know nothing about the nature of reality through the senses, a thesis
which is consistent with the slogan stated in the first half of fragment 9 and
which dissolves the apparent tension internal to fragment 7 and the second half
of fragment 9. Support for that suggestion comes from consideration of the
context in which Sextus quotes fragments 6–10, namely that of Democritus’
critique of the senses; of this Sextus observes, ‘In these passages he more or less
abolishes every kind of apprehension, even if the senses are the only ones which
he attacks specifically.’ It thus appears that Sextus understands Democritus as
referring in these fragments to the senses only, though in his (i.e. Sextus’) view
the critique there directed against the senses in fact applies to all forms of
apprehension. This is confirmed by the distinction which Sextus immediately
(Adversus Mathematicos VII.135–9) attributes to Democritus between the
‘bastard’ knowledge provided by the senses and the ‘genuine’ knowledge
provided by the intellect (fr. 11). The latter is specifically said to be concerned
with things which fall below the limits of sensory discrimination, and we must
therefore suppose that the atomic theory itself is to be ascribed to this form of
knowledge. This is supported by those passages (ibid. VIII.6–7, 56) in which
Sextus associates the position of Democritus with that of Plato, in that both
reject the senses as sources of knowledge and maintain that only intelligible
things are real; for Plato, of course, the intelligible things are the Forms, whereas
for Democritus they are the atoms, which are inaccessible to perception and,
consequently, such that their properties are determinable only by theory.
Thus far the prospects for a unified interpretation of Democritus’
epistemology look promising. The position expressed in the fragments cited by
Sextus is not general scepticism, but what we might term theoretical realism. The
character of the physical world is neither revealed by perception nor inaccessible
to us; it is revealed by a theory which, starting from perceptual data, explains
those data as appearances generated by the interaction between a world of
imperceptible physical atoms and sensory mechanisms also composed of atoms.
But now, as Sextus points out (ibid. VIII.56 (not in DK)) and Democritus
himself recognized (in the famous ‘complaint of the senses’ (fr. 125)) scepticism
threatens once again; for the theory has to take perceptual data as its startingpoint,
so if the senses are altogether unreliable, there are no reliable data on
which to base the theory. So, as the senses say to the mind in fragment 125, ‘Our
overthrow is a fall for you.’
Commentators who (like Barnes [2.8]) read fragment 125 as expressing
commitment to scepticism (despairing or exultant, according to taste) on the part
of Democritus, naturally reject the unitary interpretation proffered above. On this
view fragments 117 and 6–10 are not restricted to sensory cognition, but express
a full-blooded rejection of any form of knowledge, which must be seen as
superseding the distinction between appearance and reality of fragments 9 (first
part) and 11 and the claim to ‘genuine knowledge’ in the latter. Yet Sextus
presents 6–11 in a single context (Adversus Mathematicos VII.135–40) without
any suggestion of a conflict within the collection. Moreover, in Outlines of
Pyrrhonism I.213–4 (not in DK) he points out that, though the Sceptics resemble
Democritus in appealing to phenomena of conflicting appearances, such as the
honey which tastes sweet to the healthy and bitter to the sick, in fact Democritus
uses those phenomena to support, not the sceptical position that it is impossible
to tell how the honey is in fact, but the dogmatic position that the honey is itself
neither sweet nor bitter. (I interpret the latter as the assertion that sweetness and
bitterness are not intrinsic attributes of the structure of atoms which is the honey
(see above).) Sextus, in short, sees Democritus not as a sceptic, but as a
dogmatist. Indeed, Sextus does not cite fragment 125, and it is possible that he
did not know the text from which it comes; VIII.56 shows that he was aware of
the problem which is dramatized in the fragment, but he clearly saw it as a
difficulty for Democritus, rather than as signalling Democritus’ rejection of the
basis of his own theory.
At this point we should consider in what sense the theory of atomism takes the
data of the senses as its starting-point, and whether that role is in fact threatened
by the appearance—reality gap insisted on in fragment 9. According to Aristotle
(On Generation and Corruption 315b6–15, DK 67 A 9; 325b24–6, DK 67 A 7)
the theory started from sensory data in the sense that its role was to save the
appearances, i.e. to explain all sensory data as appearances of an objective
world. Both Aristotle (On Generation and Corruption) and Philoponus (his
commentary, 23.1–16 (not in DK)) mention conflicting appearances as among
the data to be saved; the theory has to explain both the honey’s tasting sweet to
the healthy and its tasting bitter to the sick, and neither appearance has any
pretensions to represent more faithfully than the other how things are in reality.
All appearances make an equal contribution to the theory. That is a position
which atomism shares with Protagoras, but the latter assures the equal status of
appearances by abandoning objectivity; in the Protagorean world there is nothing
more to reality than the totality of equipollent appearances. For Democritus, by
contrast, the reconciliation of the equipollence of appearances with the
objectivity of the physical world requires the gap between appearance and reality.
Without the gap a world of equipollent appearances is inconsistent, and hence not
objective. But there is no ground for denying equipollence; qua appearance,
every appearance is as good as every other. Hence the task of theory is to arrive
at the best description of an objective world which will satisfy the requirement of
showing how all the conflicting appearances come about.
So far from threatening the foundations of the theory, then, the appearancereality
gap is essential to the theory. But in that case what is the point of the
complaint of the senses in fragment 125? Surely that text provides conclusive
evidence that Democritus believed that the gap threatened the theory, and hence
(assuming that he understood his own theory) conclusive evidence against the
interpretation which I am advancing. I do not think that the text does provide
such evidence, for the simple reason that we lack the context from which the
quotation comes. The point of the complaint need not (and given the nature of
Democritus’ theory certainly should not) be the admission that the theory is selfrefuting.
It is at least as likely to be a warning against misunderstanding the
account of the appearance-reality gap as requiring the abandonment of sensory
evidence. We may imagine an anti-empiricist opponent (Plato, say) appealing to
the gap to support the claim that the senses are altogether unreliable, and should
therefore be abandoned (as is perhaps indicated by Phaedo 65–6). In reply
Democritus points out that the attack on the senses itself relies on sensory evidence.
Sextus does indeed align Democritus with Plato in this regard (Adversus
Mathematicos VIII.56). It is my contention, however, that when we put the
Aristotelian evidence of the atomists’ acceptance of the appearances as the
starting-point of their theory together with all the other evidence, including the
fragments, we have to conclude that the picture of Democritus as a failed
Platonist is a misunderstanding. The atomists’ distinction between appearance
and reality does not involve ‘doing away with sensible things’; on the contrary,
appearances are fundamental to the theory, first as providing the data which the
theory has to explain and second as providing the primary application for the
observationally-based terminology which is used to describe the nature and
behaviour of the entities posited by the theory (cf. [6.46]).
A final objection, however, comes from Aristotle himself, who describes
Democritus as concluding from conflicting appearances ‘that either nothing is
true, or it is unclear to us’ (Metaphysics 1009b11–12). This is a very puzzling
passage, for a number of reasons. Aristotle is explaining why some people go
along with Protagoras in believing that whatever seems to be the case is so, and
in the immediate context (1009a38ff.) cites the phenomena of conflicting
appearances and the lack of a decisive criterion for choosing between them as
conducing to that belief. But at 1009b9 he shifts from the thought that conflicting
appearances lead to the view that all appearances are true to the sceptical account
of those phenomena, namely that it is unclear which of the appearances is true or
false, ‘for this is no more true than that, but they are alike’. This, he says (i.e. the
belief that none of the appearances is truer than any other) is why Democritus
said that either nothing is true, or it is unclear to us. So Democritus is represented
as posing a choice of adopting either the dogmatic stance that none of the
appearances is true, or the sceptical stance that it is unclear (which is true). Yet in
the next sentence Aristotle says that because he and others assimilate thought to
perception they hold that what appears in perception is necessarily true, the
position which we have already seen him attribute to Democritus in a number of
places. So unless Aristotle is radically confused, the disjunction ‘either none of
the appearances is true, or it is unclear to us’ must be consistent with the thesis
that all perceptions are true. If ‘it is unclear to us’ is read as ‘it is unclear to us
which is true’, then the claims are inconsistent. I suggest, however, that what
Democritus said was to the effect that ‘either nothing is true, or it (i.e. the truth)
is unclear’. The first alternative he plainly rejected, so he maintained the second.
And that is precisely what he maintains in fragment 117: the truth (about the
atoms and the void) is in the depths, i.e. it is not apparent in perception, i.e. it is
unclear (adēlon) in the sense that it is not plain to see. That he used the term
adēlon to apply to atoms and the void is attested by Sextus (Adversus
Mathematicos VII.140, DK 68 A 111), who cites Diotimus as evidence for
Democritus’ holding that the appearances are the criterion for the things that are
unclear and approving Anaxagoras’ slogan ‘the appearances are the sight of the
things that are unclear’ (opsis tōn adēlōn ta phainomena). The truth, then, i.e. the
real nature of things, is unclear (i.e. non-evident), but all perceptions are true in
that all are equipollent and indispensable to theory.
If that is what Democritus held, then it may reasonably be said that ‘true’ is
the wrong word to characterize the role of appearances in his theory. ‘All
appearances are equipollent’ is equally compatible with ‘All appearances are
false’, and in view of his insistence on the non-evident character of the truth it
would surely have been less misleading for him to say the latter. Though there
are some difficult issues here, I shall not argue the point, since I am not
concerned to defend Democritus’ thesis that all appearances are true. I do,
however, accept that he actually maintained that thesis and have sought to
explain why he did and how he held it together with (1) his rejection of
Protagorean subjectivism and (2) the views expressed in the fragments cited by
Sextus.5
In conclusion, it should be observed that the persuasiveness or otherwise of
the atomists’ account of the secondary qualities cannot be separated from that of
the whole theory of perception of which it is pan, and that in turn from the theory
of human nature, and ultimately of the natural world as a whole. As presented by
the atomists, the theory is entirely speculative, since it posits as explanatory
entities microscopic structures of whose existence and nature there could be no
experimental confirmation. Modern developments in sciences such as
neurophysiology have revised our conceptions of the structures underlying
perceptual phenomena to such an extent that modern accounts would have been
unrecognizable to Leucippus or Democritus; but the basic intuitions of ancient
atomism, that appearances are to be explained at the level of the internal
structure of the perceiver and of the perceived object, and that the ideal of
science is to incorporate the description of those structures within the scope of a
unified and quantitatively precise theory of the nature of matter in general, have
stood the test of time.
Democritus’ uncompromising materialism extended to his psychology.
Though there is some conflict in the sources, the best evidence is that he drew no
distinction between the rational soul or mind and the non-rational soul or life
principle, giving a single account of both as a physical structure of spherical
atoms permeating the entire body. This theory of the identity of soul and mind
extended beyond identity of physical structure to identity of function, in that
Democritus explained thought, the activity of the rational soul, by the same
process as that by which he explained perception, one of the activities of the
sensitive or non-rational soul. Both are produced by the impact on the soul of
extremely fine, fast-moving films of atoms (eidōla) constantly emitted in
continuous streams by the surfaces of everything around us. This theory
combines a causal account of both perception and thought with a crude pictorial
view of thought. The paradigm case of perception is vision; seeing something
and thinking of something alike consist in picturing the thing seen or thought of,
and picturing consists in having a series of actual physical pictures of the thing
impinge on one’s soul. While this assimilation of thought to experience has some
affinities with classical empiricism, it differs in this crucial respect, that whereas
the basic doctrine of empiricism is that thought derives from experience, for
Democritus thought is a form of experience, or, more precisely, the categories of
thought and experience are insufficiently differentiated to allow one to be
characterized as more fundamental than the other. Among other difficulties, this
theory faces the problem of accounting for the distinction, central to Democritus’
epistemology, between perception of the observable properties of atomic
aggregates and thought of the unobservable structure of those aggregates. We
have no knowledge of how, if at all, Democritus attempted to deal with this
problem.
Theology
Another disputed question is whether Democritus’ materialistic account of the
universe left any room for the divine. According to most of the ancient sources,
he believed that there are gods, which are living, intelligent, material beings (of a
peculiar sort), playing a significant role in human affairs. They are atomic
compounds, and like all such compounds they come to be and perish. They did
not create the physical world (of which they are pan), nor, though they are
intelligent, do they organize or control it. They are as firmly part of the natural
order as any other living beings. Specifically, Democritus believed the gods to be
living eidōla, probably of gigantic size, possessing intelligence, moral character
and interest in human affairs. While some sources suggest that these eidōla
emanate from actual divine beings, the majority of sources agree that they are
themselves the only divine beings which Democritus recognized. Some modern
scholars (e.g. Barnes [2.8], ch. 21 (c)) interpret this as amounting to atheism,
taking Democritus to have held that the gods are nothing more than the contents
of human fantasy. But for Democritus eidōla are not intrinsically psychological;
they are not contents of subjective states, but part of the objective world, causing
psychological states through their impact on physical minds. In that case the theory
must explain their source and their properties, notably their being alive. Since
they are of human form, it is plausible to suggest that their source is actual
humans, possibly giants living in the remote past. They are themselves alive in
that, flowing from beings permeated with soul-atoms, they contain soul-atoms
themselves. Consistently with this naturalistic theology Democritus gave a
naturalistic account of the origin of religion, identifying two types of phenomena
as having given rise to religious belief, first the occurrence of eidōla themselves,
presumably in dreams and ecstatic states, and second celestial phenomena such
as thunder, lightning and eclipses.
Democritus’ theology thus contrives to incorporate some of the most
characteristic features of the gods of traditional belief, notably their
anthropomorphism, power, longevity (though not, crucially, immortality)
personal interaction with humans and interest (for good or ill) in human affairs,
within the framework of a naturalistic and materialistic theory. It is thus, despite
the bold originality of its account of the divine nature, notably more conservative
than some of its predecessors (especially the non-anthropomorphic theology of
Xenophanes) and than its Epicurean successor, whose main concern is to exclude
the gods from all concern with human affairs.
Ethics and Politics
The evidence for Democritus’ ethical views differs radically from that for the
areas discussed above, since while the ethical doxography is meagre, our sources
preserve a large body of purported quotations on ethical topics, the great majority
from two collections, that of Stobaeus (fifth century AD) and a collection entitled
The sayings of Democrates’. While the bulk of this material is probably
Democritean in origin, the existing quotations represent a long process of
excerpting and paraphrase, making it difficult to determine how close any
particular saying is to Democritus’ own words. Various features of style and
content suggest that Stobaeus’ collection of maxims contains a greater proportion
of authentically Democritean material than does the collection which passes
under the name of ‘Democrates’.
Subject to the limitations imposed by the nature of this material, we can draw
some tentative conclusions about Democritus’ ethical views. He was engaged
with the wide-ranging contemporary debates on individual and social ethics of
which we have evidence from Plato and other sources. On what Socrates
presents as the fundamental question in ethics, ‘How should one live?’ (Plato,
Gorgias 500c, Republic 352d), Democritus is the earliest thinker reported as
having explicitly posited a supreme good or goal, which he called ‘cheerfulness’
(euthumia) or ‘well-being’ (euestō), and which he appears to have identified with
the untroubled enjoyment of life. It is reasonable to suppose that he shared the
presumption of the primacy of self-interest which is common both to the Platonic
Socrates and to his immoralist opponents, Callicles and Thrasymachus. Having
identified the ultimate human interest with ‘cheerfulness’, the evidence of the
testimonia and the fragments is that he thought that it was to be achieved by
moderation, including moderation in the pursuit of pleasures, by discrimination
of useful from harmful pleasures and by conformity to conventional morality.
The upshot is a recommendation to a life of moderate, enlightened hedonism,
which has some affinities with the life recommended by Socrates (whether in his
own person or as representing ordinary enlightened views is disputed) in Plato’s
Protagoras, and, more obviously, with the Epicurean ideal of which it was the
forerunner.
An interesting feature of the fragments is the frequent stress on individual
conscience. Some fragments stress the pleasures of a good conscience and the
torments of a bad one (frs 174, 215) while others recommend that one should be
motivated by one’s internal sense of shame rather than by concern for the
opinion of others (frs 244, 264, Democrates 84). This theme may well reflect the
interest, discernible in contemporary debates, in what later came to be known as
the question of the sanctions of morality. A recurrent theme in criticisms of
conventional morality was that, since the enforcement of morality rests on
conventions, someone who can escape conventional sanctions, e.g. by doing
wrong in secret, has no reason to comply with moral demands (see Antiphon fr.
44 DK, Critias fr. 25 DK and Glaucon’s tale of Gyges’ ring in Plato’s Republic,
359b–360d). A defender of conventional morality who, like Democritus and
Plato, accepts the primacy of self-interest therefore faces the challenge of
showing, in one way or another, that self-interest is best promoted by the
observance of conventional moral precepts.
The appeal to divine sanctions, cynically described in Critias fragment 25,
represents one way of doing this, and there are some traces of the same response
in Democritus. While his theory of the atomic, and hence mortal, nature of the
soul admits no possibility of postmortem rewards and punishments, the theory
allows for divine rewards and punishments in this life. Fragment 175 suggests a
complication: the gods bestow benefits on humans, but humans bring harm on
themselves through their own folly. Is the thought that the gods do not inflict
punishment arbitrarily, but that humans bring it on themselves? Or is it rather that
the form which divine punishments take is that of natural calamities, which
humans fail to avoid through their own folly? The latter alternative would make
the pangs of conscience one of the forms of divine punishment, while the former
would see it as a further sanction. Either way (and the question is surely
unanswerable) we have some evidence that Democritus was the earliest thinker
to make the appeal to ‘internal sanctions’ central to his attempt to derive morality
from self-interest, thus opening up a path followed by others including Butler
and J.S.Mill.
The attempt, however pursued, to ground morality in self-interest involves the
rejection of the antithesis between law or convention (nomos) and nature
(phusis) which underlies much criticism of morality in the fifth and fourth
centuries. For Antiphon, Callicles, Thrasymachus and Glaucon, nature prompts
one to seek one’s own interest while law and convention seek, more or less
successfully, to inhibit one from doing so. But if one’s long-term interest is the
attainment of a pleasant life, and if the natural consequences of wrongdoing,
including ill-health, insecurity and the pangs of conscience, give one an
unpleasant life, while the natural consequences of right-doing give one a
contrastingly pleasant life, then nature and convention point in the same
direction, not in opposite directions as the critics of morality had alleged. (We
have no evidence whether Democritus had considered the objections that
conscience is a product of convention, and that exhorting people to develop their
conscience assumes that it must be.) Though the texts contain no express
mention of the nomos-phusis contrast itself, several of them refer to law in such a
way as to suggest rejection of the antithesis. Fragment 248 asserts that the aim of
law is to benefit people, thus contradicting Glaucon’s claim (Republic 359c) that
law constrains people contrary to their natural bent. Fragment 248 is
supplemented and explained by fragment 245; laws interfere with people’s living
as they please only to stop them from harming one another, to which they are
prompted by envy. So law frees people from the aggression of others, thus
benefiting them by giving them the opportunity to follow the promptings of
nature towards their own advantage. The strongest expression of the integration
of nomos and phusis is found in fragment 252: the city’s being well run is the
greatest good, and if it is preserved everything is preserved, while if it is
destroyed everything is destroyed. A stable community, that is to say, is
necessary for the attainment of that well-being which is nature’s goal for us. This
quotation encapsulates the central point in the defence of nomos (emphasized in
Protagoras’ myth (Plato, Protagoras 322a–323a)) that law and civilization are
not contrary to nature, but required for human nature to flourish, a point also
central to the Epicurean account of the development of civilization (see
especially Lucretius V).
I conclude with a brief discussion of the vexed question of the connections (or
lack of them) between Democritus’ ethics and his physical theory. In an earlier
discussion ([6.46]), I argued against Vlastos’s claim [6.47] to find significant
connections between the content of the two areas of Democritus’ thought.
Vlastos’s position has found some recent defenders (and my views some critics),
including Sassi [6.43]; these discussions seem to me to call for some reexamination
of the question.
It is, I take it, common ground that in composing his ethical writings
Democritus had not abandoned his physical theory, and therefore that, at the very
least, he would have sought to include nothing in the former which was
inconsistent with the latter. I shall make the stronger assumption that he took for
granted in the ethical writings the atomistic view of the soul as a physical
substance pervading the body. I remain, however, unconvinced of any closer
connection between physics and ethics. In particular, I see no indication that any
ethical conclusions (e.g. that the good is ‘cheerfulness’) were supposed to be
derived from the physical theory, or that the physical theory provided any
characterizations of the nature of any ethically significant psychological state. Put
in modern terms, I see no evidence that Democritus believed in type—type
identities between ethical states such as cheerfulness and physical states such as
having one’s soul-atoms in ‘dynamic equilibrium’ (Vlastos, in [4.64], 334). My
earlier criticisms of this kind of view seem to me to stand.
There is, however, one particular point on which I now think that I took
scepticism too far. This was in my rejection of Vlastos’s interpretation of
fragment 33, that teaching creates a new nature by altering the configuration of
the soul-atoms. My reason was that ruthmos was an atomistic technical term for
the shape of an individual atom, not for the configuration of an atomic aggregate,
for which their term was diathigē. Hence metaruthmizei (or metarusmoi) in the
fragment could not mean ‘reshape’ in the sense ‘produce a new configuration’.
But, as Vlastos had already pointed out, the catalogue of Democritean titles
includes Peri ameipsirusmiōn ‘On changes of shape’ (Diogenes Laertius IX.47),
which cannot refer to changes in the shapes of individual atoms (since they are
unchangeable in respect of shape), and must therefore refer to changes in the
shape of atomic aggregates. Further, Hesychius glosses ameipsirusmein as
‘change the constitution (sungkrisin) or be transformed’, and though he does not
attribute the word to any author it is at least likely to have been used in that sense
by Democritus, since neither the verb nor its cognates are attested to anyone else.
It therefore now seems to me that Vlastos’s reading of the fragment is probably
right. Teaching, like thought and perception, is for Democritus a physical
process involving the impact of eidōla on the soul, with consequent
rearrangement of the soul-aggregate. (Cf. fr. 197, ‘The unwise are shaped
(rusmountai) by the gifts of fortune…’) Acceptance of that causal picture does
not, of course, commit one to endorsing type-type psychophysical identities.
Psycho-physical identity having been set aside, some looser connections
between Democritus’ ethics and other areas of his thought may perhaps be
discerned. I argued [6.46] for a structural parallel between ethics and
epistemology, a suggestion which still seems to me plausible. Another vague
connection is with cosmology. It is not unreasonable to suppose that Democritus
saw at least an analogy between the formation of worlds (kosmoi) from the
primitive atomic chaos by the aggregation of atoms under the force of necessity
and the formation of communities (also termed kosmoi, frs 258–9) by individuals
driven by necessity to combine in order to survive, and it may be that the
aggregation of like individuals to like, which is attested as operating in the
formation of worlds (DK 67 A 1 (31)), had some counterpart in the social
sphere.
Conclusion
Atomism can thus be seen as a multi-faceted phenomenon, linked in a variety of
ways to various doctrines, both preceding, contemporary and subsequent.
Atomistic physics is one of a number of attempts to accommodate the Ionian
tradition of comprehensive natural philosophy to the demands of Eleatic logic.
Atomistic epistemology takes up the challenge of Protagorean subjectivism,
breaks new ground in its treatment of the relation of appearance to reality and
constitutes a pioneering attempt to grapple with the challenge of scepticism.
Atomistic ethics moves us into the world of the sophists and of early Plato in its
treatment of the themes of the goal of life, and of the relations between selfinterest
and morality and between nomos and physis. Chapters in subsequent
volumes attest the enduring influence of the atomism of Leucippus and
Democritus throughout the centuries, whether as a challenge to be faced, most
notably by Aristotle, or as a forerunner to Epicureanism in all its aspects, and
thereby to the revival of atomistic physics in the corpuscular philosophy of the
sixteenth and seventeenth centuries.6
NOTES
1 S.Kripke, Naming and Necessity, 2nd edn., Oxford, Blackwell, 1980.
2 For fuller discussion see Lesher [6.14].
3 An apparent exception is Aetius I.25.3 (DK 28 A 32, from ps.—Plutarch and
Stobaeus). After ascribing to Democritus (and Parmenides) the doctrine that
everything is according to necessity, the citation continues ‘and the same is fate and
justice and providence and the creator’. The reference of ‘the same’ (tēn autēn) is
presumably the feminine noun anangkē; Democritus is therefore said to have
identified necessity with fate, justice, providence and the creator. Apart from the
authority of this testimony, its meaning is problematic. It might be taken (in
opposition to all the other evidence), as ascribing purpose and moral content to
necessity, but could as well be taken as explaining justice and providence away as
nothing more than necessity, i.e. as saying ‘necessity is what (socalled) fate, justice
and cosmic providence really are’. Since in the next section ps.—Plutarch cites
Democritus’ mechanistic account of necessity as impact (I.26.2, DK 68 A 66)
consistency is better preserved by the latter reading.
4 In Epicurus’ own theory, chance and necessity are distinct causes (Letter to
Menseceus 133, Diogenes Laertius Lives X, sections 122–35), so if he is assuming
that the atomists share his view, the position he ascribes to them is (2). But that
assumption is not required by the text, which leaves open the possibility that the
view ascribed is (1).
5 Richard McKim argues [6.39] that Democritus held all appearances to be true in a
robuster sense of ‘true’ than that for which I argue here, namely that ‘they are all
true in the sense that they are true to the eidōla or atomic films which cause them
by streaming off the surfaces of sensible objects and striking our sense organs’ (p.
286). Though McKim does not discusss what it is for appearances to be true to the
eidōla, I take it that he is attributing to Democritus the account of the truth of
appearances which Epicurus is held by some writers to have maintained, namely
that sense impressions faithfully register the physical characteristics of the eidōla
which impinge on the sense organs. (See G.Striker ‘Epicurus on the truth of senseimpressions’,
Archiv für Geschichte der Philosophie 59 (1977): 125–42 and
C.C.W.Taylor ‘All impressions are true’, in M. Schofield, M.Burnyeat and
J.Barnes (eds) Doubt and Dogmatism, Oxford, Clarendon Press, 1980:105–24.)
While I am in total sympathy with McKim’s account of Democritus’ overall
epistemological strategy, I am unwilling to follow him in attribution of the
Epicurean theory to Democritus, since none of our evidence gives any support to
the suggestion that Democritus gave that or any particular account of the truth of
appearances. I agree that he probably held that, for the reason dramatized in the
complaint of the senses, all appearances had to be in some sense or other true if
there was to be any knowledge at all. But against McKim I hold that we have
insufficient evidence to attribute to Democritus any account of the sense in which
appearances are true, beyond the implicit claim that all appearances are
equipollent. It is plausible to suppose that Epicurus’ account was devised in
attempt to make good that deficiency. See also Furley [6.33].
6 I am grateful to Gail Fine, David Furley and Robin Osborne for their comments on
earlier drafts.
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6.32 ——[2.31], ch. 9–11.
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Taylor & Francis e-Library.
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