view, either to accept Necessity (as Democritus had done) or
to endow his atoms with Free-will, exercised not constantly,
but at uncertain intervals. It is -not every one who would
have thought of freeing himself from a difficulty in such a
way, or would have had the courage to assign free-will to *f
The latest historian of Epicureanism has called this doctrine
of atomic declination ( the central and most original point of
1 This passage from Professor Jenkin suggests to us the question, How
far does his expression as to the action of free-will hold for the moral
world ? With regard to different motives for personal conduct, the action
of free-will appears, similarly, to be rarely (in the case of most people, at
least) in violent opposition to that of impulse, but as it were slightly, yet
distinctly, deflecting the spontaneous impulse. In illustration of this we
quote from an able Eoman Catholic writer : ' I have the fullest power of
opposing my will's spontaneous impulse. . . . How far I may choose to
put forth such exertion, this is not abstractedly matter of calculation at
all. ... At the same time, it should be observed that, in all ordinary
cases, the act of will, which results in fact, is found in close vicinity to the
will's spontaneous impulse. ... In 999 cases out of 1,000 a man's
probation is carried to a successful issue by this more than by anything
else ; viz., by putting forward on repeated occasions a number of acts,
which are a little higher than his spontaneous impulse ' (Dr. W. G. Ward,
' Science, Prayer, Free Will, and Miracles,' 1881, pp. 46-7). In great
crises of personal history, involving moral and spiritual struggles, cer-
tainly this does not apply ; but for the ordinary life of most people it is,
probably, true enough.
54 THE ATOMIC THEORY OF LUCRETIUS.
Epicurus's system.' ] In order the better to understand it, we
must leave it for the present until we have examined Epicurean
The last proposition which we shall quote from Lucretius is as
follows : ( Nor was the store of matter ever more dense or_ever
separated by larger intervals than now ; for nothing is.jaJLb.er
added to it or lost from, it. Wherefore, in whatsoever motion
the bodies of the first-beginnings now move, in the same way
they moved in time gone by, and in like manner will they
always be borne along hereafter. . . . No force ^an_ajter__tlie
sum<rf things \_i.e. the universe] ; for there is nothing outside
into which either any kind_of matter_can_jgscape out of the
universe, or_out of which a new force 2 can arise and burst_in
and change alljthe nature of things and, disturb its motions/ 3
Lucretius here states that matter was never more or less dense
than it is now, and that the atoms have always moved., nnd
always will move, with the same velocity ; and because there
is nothing else outside and beyond the atoms, nothing can alter
1 M. Guyau, * La Morale d'Epicure,' 1881, p. 99, note.
2 Nova vis. Munro translates ' a new supply ' that is, of matter.
Nee stipata magis fait unquam material
copia, nee porro maioribus intervallis ;
nam neque adaugescit quicquam neque deperit inde.
quapropfcer quo nunc in motu principioram
corpora sunt, in eodem ante acta aetate fuere
et post liaec semper simili ratione ferentur,
et quae consuerint gigni gignentur eadem
condicione et erunt et crescent vique valebunt,
quantum cuique datum est per foedera natural,
nee rerum summam commutare ulla potest vis ;
nam neque, quo possit genus ullum material
effugere ex omni, quicquam est extra, neque in omne
unde coorta queat nova vis inrumpere et omnem
naturam rerum mutare et vertere motus. 11. 294-307.
We may compare v. 361 ff,
sicut surnmarum summa est aeterna neque extra
qui locu* est, quo dissiliant, neque corpora sunt quae
THE ATOM OF LUCRETIUS. 55
the snm of things, 'what we should call the energy of the
universe.' ' This proposition,' says Professor Jenkin, ' fore-
shadows the doctrine of Conservation of Energy. It is clear
that Lucretius conceived two things as quite constant : atoms
were neither created nor destroyed, and their motion could
neither be created nor destroyed. He believed that each atom
kept its velocity unaltered. The modern doctrine is that the
total energy of the universe is constant, but may be variously
distributed, and is possibly due to motion alone ultimately,
though this last point has not been yet proved.' f lf matter
in motion be conceived as the sole ultimate form of energy,
Lucretius must be allowed great merit in having taught that the
motion of matter was as indestructible as its material existence,
although he knew neither the laws of momentum nor 'of vis
viva. If energy, as he believed, be due solely to motion, then
his doctrine is true.' Thus in the concluding proposition,
Lucretius states that Force is indestructible.
Lucretius has now constructed a complete atomic theory of
the world. He has now completed the needful foundation from
which to prove that the atoms, moving of their own accord,
have created all existing things, including the body and soul of
Titus Lucretius and of all men destined to be. If you are not
convinced of this, if you are not at once prepared to do
homage to the creative atoms, the poet, like Professor Clifford,
waxes indignant, and wonders that you are so impervious to
We have now enumerated the whole series of propositions
containing Lucretius's Atomic theory. His scientific style is
admirably simple ; its simplicity and plainness convey the im-
pression of good faith. We shall refer later on to the illustra-
tions which break the severity of the argument. Apart from
their beauty of conception, they have, at the same time, in
every case, a scientific value : they show, according to Tyndall,.
that Lucretius had a strong f scientific imagination.'
THE BIRTH OF THE WORLD.
THUS far Lucretius has carried us with wonderful co-
herence. But, after following him as our guide so far,
we now come to a gap in his theory, indeed a bottomless chasm
over which he has thrown no bridge. With a single leap he
passes from the whirling atoms to the world with all its life,
beauty, and order, but hardly a word as to how the atoms have
produced it, how the supreme result is reached. Sellar says :
' He may, as was natural, have failed in adequately conceiving
the transition from the fortuitous concourse of lifeless atoms to
the exuberant life and perfect order of the world : ' perhaps it
might be more correct to say he almost totally omits any
attempt to show how this could take place. Over and over
again he asserts that the intricate and countless movements of
the clashing atoms, trying every manner of combination in the
course of their perpetual motion from eternity, have produced
the world, and that all the life upon it has resulted from the
complicated motions and collisions of these hard little kernels.
But for sole answer to the question, 'How can this take
place ? ' Lucretius gives a few vague hints. ( Truly not by
design have the first-beginnings of things stationed themselves
each in their proper places, by sage consideration, nor have
they made agreement what motions they should each assume.
Not so in truth ; the cause is that they are many in number,
and have shifted, in changes many, all the universe over. They
have been driven together^ and tormented by constant shocks
THE BIRTH OF THE, WORLD. 57
from all eternity. After trying in this way motions and unions
of every kind, they fall at length into the arrangements out of
which this world of ours has been formed, and by which too it
has been preserved in being through many cycles, when once
it has been thrown into the fitting motions.' l This passage
contains Lucretius's whole account of Evolution, certainly a
short one. He repeats it often, and frequently enlarges it by
some phrase like the following : ' At length come_together
those atoms which, being suddenly carried together, become
the rudiments ' of the world, or ' at length there filtered through
those atoms which. beina_suddenly cast together, become, from
time to time, the rudiments of great things, of earth, sea,
heaven, and of the race of living things.' 2 Lucretius holds
that there is something sudden in this atomic begetting of an
infant world. When the course of atomic combinations has ^at
last brought the fit atoms near each other^ suddenly they_leap
together, and the germ of the world ifi bo rn
1 i. 1021-30. The same passage, with slight variations, is found at
ii. 1053-63 ; v. 187-94 ; and, with fullest detail, at v. 419-31, as follows :
nam certe neque consilio primordia rerum
ordine se suo quaeque sagaci mente locarunt,
nee quos quaeque darent motus pepigere profecto,
sed quia multa modis multis primordia rerum,
ex infinito iam tempore percita plagis
ponderibusque suis consuerunt concita ferri
omnimodisque coire atque omnia pertemptare,
quaecumque inter se possent congressa creare,
propterea fit uti magnum volgata per aevoin
omne genus coetus et motus experiundo
tandem conveniant ea quae convecta repente
magnarum rerum fiunt exordia saepe,
terrai maris et coeli generisque animantum.
Tandem conveniant ea quae convecta repente. v. 429.
tandem colarunt ea quae, coniecta repente,
maguarum rerum fierent exordia semper. ii. 1061-2.
Cf. also i. 1030,
ut scmel in motus coniectast convenientis.
58 THE ATOMIC THEORY OF LUCRETIUS.
the variety in nature, the fact that all the individuals
of the same kind differ in appearance, Lucretius does endea-
vour in a vague way to account for it. In the first place, the
atoms are not all the same, but vary in form ; and things which
differ from one another are composed of atoms of unlike shape.
Secondly, the atoms admit of many modes of combination.
Lucretius often repeats the formula, l It matters much with
what others and in what position the same atoms are severally
held in union, and what motions they mutually give and receive.' 1
Its meaning is that the differences between all^bodies are
accounted for by differences in the mutual relations of the
atoms. They differ in their
* Intervalla, vias, 2 conexus, pondera, plagas,
' Concursus, motus, ordo, positura, figurae,'
' in the^spaces between them, their passages, manners of being
linked together, weights, collisions, clashings, motions,' and
also 'in their arrangement, position, JjgjJ^shapgs.' By their
differences in shape, motion, weight, and arrangempntj fhp>
various degrees of colour, sound, scent are prodqiaed. To
illustrate this he uses the letters of the alphabet. Just as the
same letters in different arrangements produce words of entirely
different meaning, so the same atoms, in different relations as
to order, motion, &c., or with some small exchange for atoms
of different form, may produce things of quite opposite quali-
ties, such as fire and air. ' There are certain bodies (that is,
the atoms 4 ) possessed of such a nature that, if they have haply
1 ii. 1007-9.
2 * Intervalla, vias ' that is, the shapes of the pores between the atoms
of each substance. Lucretius nowhere treats this subject in detail as we
should expect him to do ; but the doctrine that the shapes of the inter-
atomic or inter-molecular pores differ in each substance according to its
structure, plays an important part in his system.
3 v. 438-9 and i. 685.
4 Lucretius is here refuting the notion of elements.
THE BIRTH OF THE WORLD. 59
produced fire, the same may, after a few have been taken aAvay
and a few added on, and their order and motion changed, pro-
duce air ; and all other things may in this way interchange
with one another.' l ' Nay, even in our own verses,' he says,
' it matters much with what other letters, and in what order,
the several letters are placed. If all the letters are not entirely
alike, still by far the greatest part are ; but the words which
they compose differ through the position of these letters. Thus,
in material things as well, when the clashings, motions, arrange-
ment, position, and shapes of matter [i.e. of the atoms] change
about, the things must change too.' 2 Only as there are far
more different kinds of atoms than there are of letters, the
former can unite in many more combinations; producing diffe-
rent substances. 3 Thirdly, everything is composed of more
than one kind of atoms. ( There is nothing which is not formed
by a mingling of seeds// The more different properties and
po w ers that anything possesses, the greater number of different
quin potius tali natura praedita quaedam
corpora constituas, ignem si forte crearint,
posse eadem demptis paucis paucisque tributis,
ordine mutato et motu, facere aeris auras,
sic alias aliis rebus mutarier omnis. i. 798-802.
quin etiain refert nostris in versibus ipsis
cum quibus [sc. elementis] et quali sint ordine quaeque locata.
si non omnia sunt, at multo maxima pars est
consimilis ; verum positura discrepitant res.
sic ipsis in rebus item iam material '
concursus, motus, ordo, positura, figurae,
cmn permutantur, mutari res quoque debent. ii. 1015-22.
Tantum elementa queunt permutato ordine solo ;
at rerum quae sunt primordia, plura adhibere
possunt unde queant variae res quaeque creari. i. 827-9.
nilesse in promptu quorum natura videtur,
quod genere ex uno consistat principiorum,
nee quidquam quod non permixto seiniue constet. ii. 583-5.
cetera consimili mentis ration e peragrans
60 THE ATOMIC THEORY OF LUCRETIUS.
shaped atoms must it contain. 1 Again, life apparently depends
merely upon the regular continuance of certain movements of
the__aoms. A blow produces death by_altering the positions
of the atoms, and ^entirely stopping- the vital motions.' In
fact, Lucretius conceiv^sjjfe as a ( mode of motion.' Of course,
he has no prot^iglasm to bridge over the gulf between dead
atoms and jiving beings. In fact, it seems never to have
entered his mind that any reasonable man should doubt that
atoms, if they do exist, moving in the way he described, would
in the course of time produce life.
According to Lucretius, difference of atomic structure jn
anytwo substances is sufficient to account for any difference
in their qualities. Thus, after describing the terrific force of
lightning, he considers this amply accounted for by saying
invenies igitur multarum semina rerum
corpore celare et varias cohibere figuras. ii. 677-9.
nimiram quia multa modis communia multis
multarum rerum in rebus primordia mixta. i. 814-5.
atque eadem magni refert primordia saepe
cum quibus et quali positura contineantur. i. 817-8.
namque eadem coelum, mare, terras, flumina, solem
constituuent, eadem fruges, arbusta, animantis,
verum aliis alioque modo commixta moventur. i. 820-3.
The same is of course implied in the illustration from the letters of the
alphabet ; see the whole argument of ii. 581-99 and 661-99. Yet does
not Lucretius's explanation of lightning as formed, apparently solely, of
very small round atoms, seem to contradict this law ? Or can it be that
lightning is not included in this statement ? It is difficult to bring this
doctrine into harmony with the other points of Lucretius's atomic theory.
Yet Democritus also seems to have held the same, and, on the other hand,
to have explained the possession of any one quality in special intensity, as
caused by such a substance being formed of one kind of atoms only,
e.g. fire, on account of its extreme mobility, solely of round and smooth
atoms; see Zeller, vol. ii., p. 324 (Eng. tr.).
et quodcumque magis vis multas possidet in se
atque potestates, ita plurirna principiorum
in sese genera ac varias docet esse figuras. ii. 586-8.
THE BIRTH OF THE WORLD. 61
that the thunder-bolt is formed ' of particles especially minute
and ready to move.' l Similarly, the mind is formed of
exceedingly small, smooth, and round atoms. Lucretius feels
that if one thing is made of small, smooth, and round atoms,
and another of large, rough, and irregular atoms, this is enough
to explain any difference between the two, however great, even
all the difference which is implied between matter and mind.
In his strong belief in the unlimited potency of special differ-
ences of atomic form and structure to explain the utmost
difference between the qualities of various substances, Lucre-
tius reminds us of a capitalist who feels keenly the difference
between the commercial value and potency of one bag holding
copper farthings and another bag holding golden guineas.
But, after attentively receiving these suggestions, the reader
asks How do the variously-shaped atoms combine so as to ^^
produce objects at all ? How have they arranged themselves
in such marvellous order ? After they have united, how is the y
regularity of their movements kept up ? How do colour, scent,
and sound come out of the mere juxtaposition of atoms which
possess neither colour, scent, nor sound ? Finally, how account
for the apparition of consciousness out of atoms which are
entirely unconscious ? To these questions Lucretius attempts ^
no definite answer. In fact, Epicureanism compelled its con-
vert to swallow this dogma without explanation. But how can
this fact be accounted for ? Simply in this way, that the
scientific mind of Lucretius's day -pretty generally accepted
atoms as sufficient to prove that the world was not created by
God, and that it went on without either guidance or inter-
ference by Deity : much as the scientific mind (though far
more competent to judge) of the nineteenth century often takes
for granted that some other hypothesis, such as Evolution, could
hunc tibi suptilem cum priinis ignibus ignem
constituit natura minutis mobilibusque
corporibus, cui nil omnino obsistere possit. vi. 225-38.
62 THE ATOMIC THEORY OF LUCRETIUS.
science prove it, must imply certain important consequences as
to morals or religion ; the connection between the theory and
the result to be proved, is overleaped. So the Epicurean
argued, if jnice you allow that atoms exist, ergo, it mugtJbllow
that the world made itself.
At the same time, if we consider it closely, we see that
Lucretius's theory contains some provisions, not separately put
forward, yet constantly implied and often referred to, which
seem a little more adequate to the assumed results.
1. Of course Lucretius had no idea of what chemistry has
revealed as to the exceedingly complex chemical structure of
all forms of organic matter. We know that before a molecule
of organic matter can be produced, a most marvellous coin-
cidence of atoms must take place. Lucretius, too, explains the
origin of organic matter by a coincidence, though he realizes
hardly at all the difficulty implied in it. As we before pointed
out, 1 he applies to the combination of the atoms, producing
any kind of matter, the word concilium, which is a most
unusual term for denoting things without life. (This word
must have conveyed to Roman ears the associations of an
assemblage of living beings, and thus it implies a rather start-
ling image as applied to dead atoms. 2 ) If concilium occurring
in dead matter answers to something like chemical combination,
on the other hand, when Lucretius speaks of concilium occur-
ring in the production of organic matter, he means it to stand
for something like 'spontaneous generation.' Lucretius asserts,
as we have seen, that without concilium no kind of matter can
be produced. After concilium has taken place, that is to say,
1 See pp. 42-5.
2 One might almost suppose that he uses the word, of course only by a
metaphor, in its later meaning (which it may have had in common speecli
even in Lucretius's time), namely, ' generative union.' We cannot press
such a line as
Non fieri partum nisi concilio ante coacto, (ii. 935)
occurring as it does in the refutation of an opposite theory.
THE Blimi OF THE WORLD. 63
after molecules have been formed, he^ supposes these to act
partly as a nucleus and assist the formation of other molecules.
To exactly the same effect says Professor Clifford, when en-
deavouring to imagine the production of a molecule of living
matter and its development, f Possibly, however, the molecule
of living matter has from the beginning that power, which
belongs to other chemical bodies, and certainly to itself, when
existing in sensible masses, of assisting the formation of its
2. It is remarkable how often Lucretius applies to the union
of the atoms such words as gignere, genitali concilia, (continually
repeated by him in this sense,) which are a vivid metaphor from
living creatures. Similarly he often calls the atoms themselves
f/enitalia corpora rerum? ' the particles which beget things.'
Again, he constantly applies to the atoms a term never used
by his master Epicurus, semina, semina rerum, ( seeds,' ' seeds
of things,' a name which seems to imply a productive power
residing in them. Lucretius must have borrowed this name
from Empedocles and Anaxagoras, who applied it to their first
principles of matter. The term, though inconsistent with his
dogma that matter is ' utterly dead,' is subtly adapted by
Lucretius, for beyond question his system implies in the atoms
decided tendency and faculties for mutual combination, 3 co-
operation, and productiveness. 4 When he describes the work
1 'Lectures and Essays,' vol. ii., p. 315.
2 Cf. i. 632-3, genitalis materies, ' birth-giving matter.'
, 3 But when Professor Sellar (p. 319) translates Bk. i. 778-9, as meaning
that the atoms, ' in the act of creation, exercise some secret invisible
faculty,' he goes far beyond Lucretius's meaning. The words only mean
that the atoms are exceedingly small, and have no qualities which sense
4 Lucretius's explanation of the chance origin and gradual development
of the world out of atoms evidently implies some kind of theory of
evolution. Perhaps it is best to say that Lucretius realized the difficulties
attending such a process only very, very faintly. The following passage
from a paper published many years ago, shows to what results the doc-
64 THE ATOMIC THEORY OF LUCRETIUS.
of the atoms in building up the world and all that is on it, we
are often reminded of Tyndall's words, ' The very molecules
appear inspired with the desire for union and growth.'
3. Though Lucretius does not specify it separately, it is
plain that infinite past time plays a very important part in_his
trine of atomic declination may be interpreted : ' An atom that is pos-
sessed of volition, and can alter its direction at will, is certainly intelligent ;
or (since Lucretius flatly denies that atoms are intelligent), it is as good
for our purpose as if it were so ; it acts as if it were intelligent. When
Lucretius assumes that atoms can swerve from their path the least distance
possible, it seems a very small thing. Beyond question, if an atom could
have free-will, as far as one could imagine, this is just the use it would
make of it. It certainly could not use a will of its own in a more modest
or less objectionable way. But, in reality, a great deal is granted by
this. . . . We now get a truer conception of what the atoms really are.
They are not like motes in the sunbeam merely, or the- drops in a shower
of rain. As we can now imagine them, they are rather like the_ crowd
pouring through the streets of a great city, every individual of which lives
and has a will of his own to direct his course, or to turn from the path of
the rest as he desires. If we conceive an atom as able to turn to the right
or the left at will (and atoms of discretion will, of course, do this on the
most necessary and suitable occasions), there is, perhaps, no very great
difficulty in their producing the world and its contents. Not more re-
markable, perhaps, than for a band of masons and carpenters to build a
house. Moreover, only upon this hypothesis in which the atoms become,
as it were, tiny workmen, building up the world, can Lucretius's atomic
theory be conceived at all possible as an explanation of how the world and
all its contains came into being. Like zoophytes building a coral reef, the
mechanic atoms ply their mighty toil far beyond our senses' reach. Of
course this is absurd, the reader says at once ; not merely absurd, but
glaringly self -contradictory, for has he not laboured to prove that the
atoms are non-sensile, only senseless, dead matter ? . . . But, perhaps,
this whole view of the matter is only an outside one. Perhaps we have
not yet grasped Lucretius's real position.'
Atoms such as we have here described, busily building up the fabric of