Anaxagorus was the first philosopher to visit Athens. Burnett
described him as a Persian soldier from Klazomenai, a Greek city
that had been conquered by the Persians. He was a teacher of
Pericles, and a student of the school of Anaximenes. He was
banished from Athens for saying that the sun was a
red hot
stone
and that the moon was like earth. Anaxagorus began by trying to
explain the world in a Milesian sense while respecting the
conclusions of Parmenides. Empedokles had taught that everything
in the world was made from four basic elements. Anaxagorus
denied this possibility. He said that there was a little of
everything in everything. Or else how could hair be made of what
is not hair unless hair was part of it. All things are together,
was the way he put it, and everything however small or great had
an equal number of portions of the opposites. Matter is
infinitely indivisible. No matter how small you may divide
anything it still had the same number of opposites. However,
everything gives the appearance of that which is most in it.
Therefore air is that which has in it most cold, fire has in it
most heat, and so on.
LEUCIPPUS
Of all of the followers of Parmenides by far the boldest was
Leucippus who challenged the basic thesis of the masters
philosophy, that what is not cannot be. When Pythagorus
developed his theory of the one and the many, the many were
separated by the void, or what is not. Parmenides rejected this
idea. Leucippus revived it. Following the lead of Parmenides,
Leucippus argued that what is must be one, but it is a plenum, he
said, a plenum filled with an infinite number of bodies each of
which meets all of the requirements of the one but are separated
from all others by the void. These he called atoms. They were
infinitely hard and indivisible, they came in a myriad shapes and
sizes, and everything that exists is made up of them. This idea
was further developed by Democritus and we will discuss him later
because he was a contemporary of Plato, and like him a student of
Socrates.
Undoubtedly the most important lesson to be learned in this study
of the presocratic philosophers is that they raised more
questions than they answered. 2600 years of philosophy and
science have showed just how elusive the answers to these
questions can be. But they set down a challenge to the western
heritage that was to follow. The world is rational, it is
understandable. It is through this understanding, based on that
assumption, that has forced the west to reject magic and
superstition as sources of knowledge. Next we shall look at the
work of Plato, the first of the long line of philosophers who
helped to develop answers to the questions posed by the presocratics.