Atomism: Democritus and Epicurus
In the Atomists, we see pluralism taken as far as it could possibly go.
We see Democritus and Epicurus divide all the world, as well as the universe,
into two categories; atoms and empty space. Everything else is merely thought
to exist. The atoms are eternal, infinite in size and number and they are
moving through the empty space. There is no motion without empty space. Both
Democritus and Epicurus agreed that motion was impossible in a plenum, but it is
here that their theories diverge. In the cause of the motion, we begin to see a
variety of opinions.
Both Democritus and Epicurus agreed that the qualitative world of sense
perception arises from the motion of qualitatively neutral atoms. They believe
that the immense qualitative variety results from the jostling’ of atoms…as
they collide and bounce apart, and so, constantly form new groupings (Jones 84).
They believe it to be a mechanical process occurring completely by chance.
Furthermore, although new groupings are constantly being formed, only the few
that can survive are considered the right combinations. These are the
combinations we recognize through our senses as being real, although they are
not. However, the way in which this complex motion begins is a source of
controversy and disagreement amongst the Atomists.
Democritus assumes that the atoms’ motion is perpetual. The atoms are
never at rest. He presumes that their nature is to move, thereby avoiding the
problem of explaining the origin of the complex motion of atoms by simply
affirming that it is in their nature to move so (Jones 85). He believes that
atoms are born along with the whole universe in a vortex. The vortex is not an
outside influence, but rather the motion of the atoms themselves. He never
accounts for the initiation of this motion. He simply states that it is an
inherent quality of the atoms themselves.
Epicurus, on the other hand, wanted to find a reasoning behind the
initial movement of the atoms; to find the cause of the initial collisions
which start the creation process of the universe.
Through observation of objects falling down within our limited
perceptual space, Epicurus concluded that in the vastness of infinite space
there can be no down since there is no point from which, or to which, an
object (in this case an atom) is falling. Since an objects’ natural state
seemed to be rest, Epicurus decided that it was not motion, but lack thereof,
that is in a things’ true nature. Therefore it is motion which requires an
explanation (Jones 85).
Since it is agreed that the atoms must collide in order to form objects
that possess different qualities, the frequency of these collisions must be
infinitely large. How else can one account for the variety of objects
recognized as normal? The space in which the atoms are traveling is large
beyond our every conception of size, and the atoms are small on the very same
scale. The probability of even two of these atoms colliding while they fall
through the void is minute, if not non-existent.
Epicurus attempts to explain these collisions with his swerve theory.
In this, he holds there is an arbitrary, imperceptible swerve in the straight
falling path of the atoms. Rather than contribute the collisions to the nature
of the atoms themselves, he is attempting to account for the frequency of
collisions, and in effect increase the probability of two atoms colliding in
There are many problems with this postulation. In effect, it is no
better an argument than Democritus’ nature theory. If we begin to assume that
events simply happen arbitrarily, we do not gain any deeper insight than we do
by saying that these events are in the nature of things. Both of these
positions lead us away from Atomism, since we are beginning to affirm the
creation of something out of nothing, a position to which the Atomists are
Modern philosophers like Dr. Jones, allow for Epicurus’ swerve theory
since given one swerve the system can develop, for it is plausible to suppose
that colliding atoms react in different ways. Some leap back at great space
apart, others are thrust but a short way from the blow’ (Jones 88). Ambiguous
as it is, Epicurus could not logically come to another conclusion without
violating his earlier teachings.
Another point on which the Atomists disagree is the nature of
qualitative differences such as weight and color. Although both Democritus and
Epicurus agree that atoms are without these qualities, their explanations of the
phenomenon of their existence are quite different.
Democritus, attempting to maintain the integrity of Atomistic physics,
says that qualitative differences are, in fact, illusions. Neither atoms, nor
empty space possess these characteristics, therefore, Democritus concludes, they
must be illusions. He supports this theory by saying that the motion of the
atoms that constitute the sensed object causes some of the atoms of that object
to be flung into the path of the atoms of the sensory organ, which in itself is
a collection of atoms in motion. Thereby, the collision of the atoms which are
moving from the object being sensed set the atoms of the sense organ in motion.
The motion perpetuates the illusion of qualitative variety. With this argument,
Democritus is able to account for the differences of opinion regarding an
objects’ qualities. What smells sweet to one, may smell foul to another.
Antithetically, Epicurus attempts to explain sensory phenomenon in a
clearer way. His explanation, however, again deviates from the core
declarations of Atomism. Epicurus agrees that atoms themselves have no
qualitative differences. Nonetheless, he declares that groups of atoms can
develop a quality such as color. He theorized that the qualities we perceive
are a by-product of the motion and collision within atomic groups themselves.
As the group moves, the qualities change. These qualities Epicurus called
properties’ not accidents’ of combinations or collections of atoms. A property
is a characteristic that some entity necessarily has; an accident is a
characteristic that is temporary and transient. Thus, in accordance with these
definitions, color is a property of atomic collections (for all such collection
have some color or other), and red’ is an accident. Though a collection is
necessarily colored, it is not necessarily “red (Jones 89).
Therefore, Epicurus attributed the qualitative differences not to our
perception, but to the atoms themselves. We come to an impass here. We have
already decided that all that exists are atoms and empty space. Epicurus then
goes on to state that the qualities are not illusions, yet they do not exist as
part of the atoms, nor do they exist within the void. Where, then, are these
qualities? Epicurus ambiguously calls these qualities accompaniments yet
never explains how they can exist outside of reality and still be considered
Epicurus changed the doctrine of Democritus in many ways in an attempt
to clarify some of the more questionable postulations. Epicurus’ theory is not
necessarily superior, but certainly progressive. There is room for discourse on
a variety of the Atomists’ theories. Since they are the first school of thought
from which we have so much written record, there is bound to be divergence of
opinion. The areas I have discussed relate only the area of physics. Epicurus
attempts to resolve some of the dilemmas Democritus leaves unresolved in ethical
and psychological dilemmas as well.
Of course, lingual and interpretive constraints play a part in all
philosophical theory of the classical period. Yet in our “modern” world, we
rely heavily on the ideas set forth by these great thinkers. It would be
foolish to take one concept as superior over another because the scope of ideas
given to us by these thinkers is too great a wealth to judge subjectively.